Singapore 5A, Specific Lessons

Lainie
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Singapore 5A, Specific Lessons

Visualizing how to multiply & divide fractions

This summer we checked out this book called The Lemonade War by Jacqueline Davies. I read the book first because I wasn't familiar with the author, etc... I let my older two read it (11 & 10) with discussion (topics like divorce and jealously, etc...)

But I didn't realize until recently how much that book helped me with math!

Trying not to write spoilers, the book is about an older boy who struggles with math and his bright little sister who will be advanced into his grade and his struggles with not feeling smart. They have a lemonade stand contest and the story ends very well. But all along his journey he practices putting algebraic math into "pictures" that he can wrap his brain around and guess what? My brain wrapped around it.

I can now help my dd with her Singapore 5A math. It's been a blessing and I am so encouraged to "get" something that has eluded me all my life. Just thought I'd share in case there are other very visual, math challenged parents out there.

An example of a problem would be 5A textbook pg 64 # 38 "Mrs. Meier had 3/5 kg of sugar. She used 1/4 of it to make cookies. How much sugar did she use to make the cookies?" This question would have fried my brain before reading this book.

But now I draw a picture like this- O O O O O (this is a kg of sugar in fifths)
then • • • O O (I don't normal "type" math so I'm making do here but this is 3/5 kg)

Then I made lines quartering each dot so each dot had 4 "pie triangles"

I'm no longer looking at a kg broken down into fifths but in 20ths.

you still with me? Now I have to find out how much of a kg she used when she started out with 3/5 or 12/20.

Well I can look at it and see that 1/4 of my original 3/5 (12/20) is 3 "triangles" worth or 3/20 which is the answer.

For those of you that have math brains I'm sure this process seems ridiculous but for us "picture" people it's freedom at last!!!

I hope I didn't give you a headache :)

ps Now that I did the problem visually I can sort of see how to set it up to do that whole cross multiply and divide deal but I can't ever remember how to set things up by just looking at the problem.

I know--I'm weird---as I tell my daughter, "Honey, we have other gifts!"
Lainie (Oregon)
"Sanctify them in truth; Thy word is truth" John 17:17

Have completed 1st, entire 5 year cycle, and all high school! Whoo hoo!
Have graduated one with MFW, 1 dd- junior, and 1ds- freshmen
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cbollin
yeah!!! Sounds like the Singapore bar diagram method (except with circles and triangles to draw instead of rectangular bars) Great job!!!!!!! (cool. all excited for you!!!) yes!!!! don't you love how to picture those kinds of problems. It's as much about learning the concepts and how to set it up instead of plugging and chugging formulas. yes!!!

-crystal
Julie in MN
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Singapore 5A Exercise 26 Number 4 HELP!!

4/7 of a group of children are boys. If there are 18 more boys than girls, how many children are there altogether?

I have the HIG for Singapore, but the way to find the solutions to this workbook page is not in there, so if someone could help us, that would be fantastic!
Hi Courtney,
I just have a minute, but I'll try. Thanks for posting the details of the problem, so we don't have to dig out a book
courthart246 wrote:4/7 of a group of children are boys. If there are 18 more boys than girls, how many children are there altogether?
First we know the 4/7:

/-------/-------/-------/-------/ boys

/-------/-------/-------/ girls

Then we know that there are 18 more boys. Hmmm... looks like one bar is equal to 18, since there is one more bar on the boys' side and there are 18 more boys, so those are the same things.

Does that make sense?
Julie
courthart246 wrote:Ah, yes. That makes perfect sense. Thanks so much. If there is not an exact example given of how to figure out a story problem, I really struggle to figure it out on my own. I do not have a math brain for sure. I have loved Singapore math except for the story problems for this very reason. I really appreciate your help.
Julie, married 29 yrs, finding our way without Shane
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Jami
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Singapore 5A Exercise 27 Number 3 HELP

courthart246 wrote:Ok, I've got another one that we need help with (Have I mentioned how much I detest story problems?):

Larry spent 1/2 of his money on a camera and another 1/8 on a radio. The camera cost \$120 more than the radio. How much money did he have at first?

Any help would be greatly appreciated!
Thanks!
I have to draw a picture for the word problems before I can figure out the math sentence because I also don't like word problems.

1/2 - 1/8 = 3/8
\$120 divided by 3/8 = \$320

I hope that is the way it's supposed to be set up. I got the correct answer anyways.

We just passed these exercises and I'm liking geometry a lot better!
Jami - AF Wife

8th, 5th, 3rd, 1st, Pre-K

2014/15 ECC
2013/14 1850MT & 1st
2012/13 EX1850 & K
2011/12 RTR & 1st
2010/11 CTG & K
2009/10 ECC & 1st
Julie in MN
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Re: Singapore 5A Exercise 27 Number 3 HELP

courthart246 wrote:Larry spent 1/2 of his money on a camera and another 1/8 on a radio. The camera cost \$120 more than the radio. How much money did he have at first?
Another way to look at it "Singapore style":

Hmmm, Larry spent half his money
/--------------------------------------/ spent
/--------------------------------------/ didn't spend

Okay, and another 1/8, wait, I need to divide those down further. I need at least 8 bars in order to have something that is 1/8th. Hmmm. Back to "Larry spent half his money," but now in 8 parts.
/----------/---------/---------/----------/ spent
/---------/----------/----------/---------/ didn't spend

Okay, now that I have 1/8ths, I can move one of the 8ths over to the spent side for the radio
/----------/---------/---------/----------/---------/ spent
/---------/----------/----------/ didn't spend

Next, I find out that the camera cost \$120 more than the radio. Woops, I have those two things combined together, so I'll take them apart. Let's see, it was the original half on the camera and 1/8 on the radio, so...
/----------/---------/---------/----------/ camera
/---------/----------/----------/ didn't spend

So now, we can look back to the fact that the camera cost \$120 more than the radio. So, three bars are equal to \$120. Therefore, it's not hard math to figure out that one bar is \$40 (it's usually a hint in Singapore that you're not having to figure hard math to do the word problems -- if you do find yourself figuring hard problems, you probably should try to do it another way).

So if one bar is \$40, then the total of 8 bars is \$320.

Just trying to show how we would think it thru, sometimes hit dead ends, but just keep playing with it.
Julie
Julie, married 29 yrs, finding our way without Shane
(http://www.CaringBridge.org/visit/ShaneHansell)
Reid (21) college student; used MFW 3rd-12th grades (2004-2014)
Alexandra (29) mother; hs from 10th grade (2002)
Travis (32) engineer; never hs
Julie in MN
Posts: 2909
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Location: Minnesota

Re: Singapore 5A Exercise 27 Number 3 HELP

Jami wrote:Now I have the question...LOL

Julie, the way you worked out the problem is the same way I did it too, before I came up with the math sentence.

Do you think we need to know a formula (or word sentence) to complete word problems like this? I just wonder if we need one for if the numbers were higher or it was harder to work out? Do you know what I mean? Or is that something that can wait for algebra? Thanks for any thoughts.
Jami,
I didn't use anything but bar diagrams with my son.

I'm sure if you take it to the next step, it will benefit your child towards understanding more advanced math. I guess I'd look at whether the child was able to understand and use the method yet, since it is a bit abstract and hasn't been reinforced a lot in the lesson. At this stage, the key is "thinking" and not "formula" -- at least IMHO. You don't want kids to get in the habit of plugging in a formula without thinking, and lose those wonderful Singapore skills of thinking about math. But in general, I think Singapore is conducive to learning to think about math in as many ways as possible!
Julie
Julie, married 29 yrs, finding our way without Shane
(http://www.CaringBridge.org/visit/ShaneHansell)
Reid (21) college student; used MFW 3rd-12th grades (2004-2014)
Alexandra (29) mother; hs from 10th grade (2002)
Travis (32) engineer; never hs
mfwstudent

Singapore 5A Exercise 29 HELP!

courthart246 wrote:Here is my current problem:
Mrs. Klein made some tarts. She sold 3/5 of them in the morning and 1/4 of the remainder in the afternoon. If she sold 200 more tarts in the morning than in the afternoon, how many tarts did she make?

I know there is probably some easy solution to this, as was shown to me in another problem I asked about yesterday, but I just can't see it. If someone could help, that would be great! Thanks.
Hi Miss Courtney,
This is how I would do that problem with "equivalent fractions". My little sis did this one a few weeks ago with me when mom was cleaning. Mom said to type over here to try to help because she is still cleaning the kitchen floor and learning new routine set for her exercise class.

We know this
3 out of 5 bars were sold in the morning and 2 out of those 5 are remaining.

____ ____ _____ | _____ ____

well, now we know with the 2 remaining bars, if we cut each bar in half we can have 4 pieces. Then it is easy to see 1/4 of the remaining.
As long as we are going to cut those bars in half, let's just cut the first 3 bars in half too, so now we are dealing with 10 bars.
6 were sold in the morning... and 1 bar in the afternoon

__ __ __ __ __ __ |__ __ __ __

5 of the morning bars is the more than the one afternoon bar and
those 5 bars are the same as 200

so, take 200 and divide it equally in those 5 bars. 40 in each bar.
that means there are 10 bars of 40.
or 400 total.

-MFW Student
mfwstudent

Re: Singapore 5A Exercise 29 HELP!

well, one other way to think about it.

Notice the 5 bars that equal 200?
well, that's half of the total bars, right (5 and 5 is 10)
so, just double the 200 and get 400.

But that was too much for my sis to get, so she did it the longer way. :D
cbollin

Need help on two different Singapore problems

Amy C. wrote:Problem 1: 5A workbook Exercise 10 problem # 4
Lily and Sarea each had an equal amount of money at first. After Lily spent \$18 and Sara spent \$25, Lily had twice as much as Sara. How much money did each have at first?

My husband figured this out, but not the Singapore way, and I would have never figured it out the way he did. I am just needing to know the Singapore way so that my son can see it.

Problem 2: 5A textbook practice 1d probem #10
John and Paul spent \$45 altogether. John and Henry spent \$65 altogether. If Henry spent 3 times as much as Paul, how much did John spend?

Amy C.
I didn't even have to look the first one up or read the rest. That is THE problem that made us fall in love with Singapore and bar diagrams. (thank you Julie)

The key to this problem to help them see it all.
think of 25 in terms of 18 plus 7 because they started with same amounts. think of the spending in terms of how it related to each other.

let's draw the problem as best as possible on a forum

__________________________

__________________________

next, we can think of it as
Lily spent 18,
Sara spent 25 which is 18 + 7.
why do we think of that? because we know they had equal stuff to start so it helps to draw it when they are related like that.

now. the new bars are the parts remaining. The problem tells us that what Lily has left is 2 bars compared to what Sara has left.

18 + ________ + _________
is the same as
18 + 7 + ________

hmm..
18 + 7 +________ = 18 plus ______ + ________

you know... that has to mean that one of those little bars is 7.
(draw it out, play with blocks to get it... show it with real stuff)

so you can take 18 and add 14 to get 32
or you can take 25 and add 7 to get 32.
back with problem 2 in a bit if someone else doesn't get it first.
cbollin

Re: Need help on two different Singapore problems

Amy C. wrote:Problem 2: 5A textbook practice 1d probem #10
John and Paul spent \$45 altogether. John and Henry spent \$65 altogether. If Henry spent 3 times as much as Paul, how much did John spend?
This one requires some thinking and playing with it. Part of the Singapore stuff involves getting the child to draw what they know and see where equal things can be subbed in. So, it's ok to play around here a bit. So, I can't find my 5A text to know if this is the advanced thinking problem to learn to sub out 2 parts for a whole and learn it. But it comes down to knowing commutative and associative properties of addition even if you don't use those terms with your child.

Paul gets the single bar b/c we know that Henry is described as 3 Pauls.
Paul - _______
Henry _______ _________ ________

actually, what I might do is draw stick figures for the guys to make it more concrete.

so we can sub out names here.

John and Paul spent \$45. Let's think of them as a team on it.
John and Henry spent 65.

That means we can say John and 3 Pauls spent 65.

J + P = 45
J + P + P + P = 65.

oh wait a minute... look in that second line (equation there)
it says (J + P) + P +P = 65
That means 45 and 2P = 65
(do we know the whole? yes, 65, do we know a part, yes 45, so we subtract. learned that in 2A)
so 2 P's is 65-45
2 p = 20
Paul = 10

well, John and 10 = 45, so John spent 35.

Yes, this is basics of 2 equation systems, but if you draw it as stick figures for the boys, or as bar diagrams it stays more concrete.

does that help any?
-c
Amy C.
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Re: Need help on two different Singapore problems

Thanks for the help on the first problem, Crystal. That is basically how my husband worked it out without the bar diagrams. My son seems to get it, but it makes my brain hurt. As long as my ds understands it, though, right.

I am so glad my dh is math minded. He said that math was the only reason he made it through school. He did say he thought that this problem was way advanced for a 6th grader. I told him that I thought that there were 1 or 2 problems per section that were advanced and that this must be "the one" for this section. Or at least it was advanced for me.

And thanks for the help on the second one as well. That does make sense. I just could not make sense of it on my own.
cbollin wrote:yep yep. you get the challenge problem for those who love a challenge. and for others, it's good to at least walk them through something harder to use what you do know in new ways.

One of the pet peeves of a university colleague of my dh has to do with how he couldn't stand hearing undergrads in chemistry not have a clue how to approach a problem that they didn't have an exact sample to follow. So, it's good, in my opinion, to give those one or two problems per section like that.

Just wait a few more weeks in 5B when you do some ratio problems and get to pull together all of the information you learned about equivalent fractions to do a few of the build in challenge problems.
Oh, goody! Sounds like loads of fun.

I am just hoping that we can get through 5B before 7th grade. We have from now until Aug. He just started 5A about a week and a half ago. He has completed through Textbook Practice 1D (using MFW lesson plans) as of today. He seems to be doing really well. We just had a lot of catch up to do since we just started with Singapore 2 years ago. Do you think we can do it? Is there a plan B in case we don't? We are going to work really hard through the summer, but I do hope to be able to take a little break (maybe a month) before starting up again.

Amy C.
cbollin

Re: Need help on two different Singapore problems

Amy C. wrote:I am just hoping that we can get through 5B before 7th grade. We have from now until Aug. He just started 5A about a week and a half ago. He has completed through Textbook Practice 1D (using MFW lesson plans) as of today. He seems to be doing really well. We just had a lot of catch up to do since we just started with Singapore 2 years ago.

Do you think we can do it? Is there a plan B in case we don't? We are going to work really hard through the summer, but I do hope to be able to take a little break (maybe a month) before starting up again.

Amy C.
My plan B is...
keep working through summer.
when we finish 5B, take a day to celebrate that we got it done!
then start 8/7 the next day.

We're in a situation where my daughter is doing more on drills to speed up math facts. she's just not a fast learner or super fast worker. and then I get into a mode where I'm not driven to have to complete the book each day with her. I should, but I shouldn't. I can't explain the reason that well, but I just have this feeling that if she starts 8/7 in late September instead of late August, it's ok for her based on all other factors considered in her situation and our real life.

-crystal
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Singapore 5A, page 27, #4 in workbook help

TriciaMR wrote:Okay, this is the first time I've gotten stuck on a word problem. Sigh... Someone please help...

Lily and Sara each had an equal amount of money at first. After Lily spent \$18 and Sara spent \$25, Lily had twice as much as Sara. How much money did each have at first?

So, I drew something like:

Code: Select all

``````|------|------|-\$18--|
|------|-----\$25-----|``````
But my brain is totally failing on what to do next, but maybe I drew it wrong to begin with.

(The answer is \$32 in the answer key, but I can't see how to get there)

-Trish
I'm not sure the proper way to figure out the problem, but I can see why the answer is \$32.

Starting with \$32 dollars, sarah spends \$25, so she has \$7 left.

Lily spent only \$18, so she has \$14 left, which is \$7+\$7 - twice as much as Sarah.

Another way to look at it: , if you take \$25 and subtract the \$18, the remainder is \$7, telling you that Lilly had \$7 more than Sarah, and she had double that total, so \$14. Add 18 plus \$14, and you get \$32.
Misty, Wife to a wonderful man! Mother to:
Rosy age 8 - 3rd grade, ECC
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TriciaMR
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Re: Singapore 5A, page 27, #4 in workbook help

Misty,

Thank you! My brain was just not processing this for some reason. I need to be able to explain why we're doing each step to my daughter or she won't get it either.

-Trish
Trish - Wife to Phil, Mom to Toni(18), Charlie(14), and Trent(14)
2014-2015 - AHL, CTG
2015-2016 - WHL, RTR
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4in4years
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Re: Singapore 5A, page 27, #4 in workbook help

Originally
Lilly had |_____| + |_____| + \$18

We know the girls’ total starting amounts are equal, so the difference between \$18 and \$25 must equal one section of the bar graph.

\$25
- \$18
__
\$7
So

Lilly is \$7 + \$7 + \$18 = \$32 and
Sara is \$7 + \$25 = \$32
cbollin

Re: Singapore 5A, page 27, #4 in workbook help

Hey Trish,

I didn't read the other answers, yet... I will... I just want you to know that without even reading the problem, I knew which one it was. You see.... it was the first time in singapore that I went "what?" and emailed Julie for help.

this is probably repeated information...... I'd recommend having your daughter build the \$25 as "18 plus 7", then, it kinda pops out how the amounts are related.

Lily and Sara each had an equal amount of money at first. After Lily spent \$18 and Sara spent \$25, Lily had twice as much as Sarah. How much money did each have at first?
Red shows the after. Red + Black shows before (these should be the same length... on the bars, but that might not show on computer)

|--------|--------|---18---|
|--------|----------25-----|

The difference between 25 and 18 is the same as one red bar unit.
and we are told in the problem that one of them had 2 bars left compared to one bar left of the other.

-crystal
cbollin

Needing help with Math-Workbook 5A, Ex.10, #4

Jamie wrote:Yes....My son thinks this is pretty funny that even his Mom can't figure out his math problem. Any ideas on how to work this problem? I've been working on it, but can't quite get it. Thank you!!! (The answer is 32)
I know that problem very well without even looking..... that was the problem that made me a Singapore convert!

take a look at some ideas on here

http://board.mfwbooks.com/viewtopic.php ... ily#p78367

-crystal
Julie in MN
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Location: Minnesota

Re: Needing help with Math-Workbook 5A, Ex.10, #4

Jamie wrote:Crystal, you make me giggle! Thank you.....

Okay, so we found out how to do it....but, we both agreed that we probably couldn't have figured it out without a little nudge. My brain is still swimming a bit. Any tips for this Mommy brain? Should I be thankful for those Dive CDs next year?
I can show you how we thought thru them at our house. Basically, it's a matter of just "try something and see what happens." After a while, you have more past experiences to throw in the pot.

So, copying from Crystal's copy of the question, this is what it would look like at our house.

Okay, first it says:
Lily and Sara each had an equal amount of money at first.
So maybe we'd draw:
/--------------------------/ Lily
/--------------------------/ Sara

Next:
After Lily spent \$18 and Sara spent \$25, Lily had twice as much as Sarah.
/------/------/ Lily
/------/ Sara

Now, what else do we know? Have I drawn every bit of info into a diagram?
Oh, I need to add "Lily spent \$18 and Sara spent \$25."
/------/------/ + 18 Lily
/------/ + 25 Sara

Okay, I think we've drawn everything so far. Next sentence:
How much money did each have at first?

I guess that means that I need to know how much "2 bars + 18" is,
OR, how much "1 bar +25" is?

Let's just stare at the diagrams above for a while and see what else we can see in there.
Okay, I can see that 25 = 1 bar +18, right?
And I know that 25 = 7 +18...
So now I've figured out something important... 1 bar = 7!!!

If I know what 1 bar is, then I can do all kinds of things...
including figure out how much they had at the beginning!

Does that make any sense? Does it sound do-able at your house?
Julie
Julie, married 29 yrs, finding our way without Shane
(http://www.CaringBridge.org/visit/ShaneHansell)
Reid (21) college student; used MFW 3rd-12th grades (2004-2014)
Alexandra (29) mother; hs from 10th grade (2002)
Travis (32) engineer; never hs
cbollin

Re: Needing help with Math-Workbook 5A, Ex.10, #4

I like Julie's description of the draw what you know to figure out what you don't know.

here's another thread where I described a bit more of my thinking process. similar to Julie's... but with my twist in my house..
http://board.mfwbooks.com/viewtopic.php ... ily#p74567
(ps. scroll in that thread for help on another problem coming up real soon in the book)

Some people like the Home Instructor Guides for Singapore. That might be nice. Check rainbow resources.

Some of the Mommy brain tips in general with Singapore in this level:

*draw what you know. talk through it.

*don’t be afraid to draw it again if it goes nowhere

*equivalent fractions will become your friend soon. they really will. you'll really love them in ratios. sometimes you get to redraw your diagram after you remember that.

*you do a lot of compare this to that, so sometimes if you stack the bar diagrams in a vertical line you can see how they relate to each other.

in this problem: Bob spent half of his money on Thing B, and 1/8 of his money on Thing A. If Thing B is \$120 more than thing A, how much money did Bob start with?
(WHAT? You’ll get there in a few weeks, it's ok. ((((hugs)))) Don't Panic

Well, we have equivalent fractions. Thing A is one of eight parts. Thing B is 4 of 8 parts.

thing A = xxxxx
thing B = xxxxx xxxxx xxxxx xxxxx
rest of money = xxxxx xxxxx xxxxx

then it helps you to see how things compare. Ah, Thing B is 120 more than A. So that means 3 bars is 120. each bar is 40, and we have 8 bars total. For 320 dollars.

My real point with that was to show how you can see the more than with 3 bars when they are top to bottom like that.

*don’t be afraid to try, try again…. Sometimes there is more than one right way to reach the answer

*enjoy learning the process as you go along. I know I did. Julie gave me a quick, brief lesson on bar diagrams when I was new to Singapore. and then oldest and I had fun in the book. then I had fun with middle and teaching her.

by the way... my middle gal isn't using the DIVE cd yet. She's reading Saxon and getting it. She was slow through Singapore and we did finish 5B by end of 6th grade (if you count the summer.)

-crystal
Jamie
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Location: Montana

Re: Needing help with Math-Workbook 5A, Ex.10, #4

Thank you, ladies! What a blessing to have this forum so I can pick everyone's brains! I truly appreciate the time you gals spend responding to all the questions.

Will you hold my hand just a bit longer?
Julie in MN wrote:Okay, I can see that 25 = 1 bar +18, right?
I'm understanding all the great descriptions, but trying to understand this one in particular. How do you know that 25 = 1 bar +18?

Thanks!
Jamie
Married to my sweetie for 16.5 years
14 ds, 12 dd, 10 dd, 7 ds, 4 ds, 1.5 dd
MFW K, ECC, CtG, RtR, Ex to 1850, & 14 yo currently in 1850 to Modern
cbollin

Re: Needing help with Math-Workbook 5A, Ex.10, #4

Jamie wrote: Will you hold my hand just a bit longer?
Julie in MN wrote:Okay, I can see that 25 = 1 bar +18, right?
I'm understanding all the great descriptions, but trying to understand this one in particular. How do you know that 25 = 1 bar +18?

Thanks!
We know that 25 is 18 plus a bar because of how they relate to each other in the problem. Both of them start with the same amount. the one gal is left with 2 bars, the other gal is left with 1.

this diagram
|--------|--------|---18---|

equals

|--------|----------25-----|

so chop off that first bar from both gals to just make it easier to see,
and we are left with

|--------|18|
equals
|25|

bar + 18 = 25
(going back to singapore 2A.... Do we know the Whole? Yes. 25. Do we know a part? yes. 18. so we subtract to find the other part.) 25-18 = 7.
each bar is 7.

and of course... keep asking as needed

bars are hard to draw on here.
Julie in MN
Posts: 2909
Joined: Mon Jun 28, 2004 3:44 pm
Location: Minnesota

Re: Needing help with Math-Workbook 5A, Ex.10, #4

Jamie wrote:Will you hold my hand just a bit longer?
Julie in MN wrote:Okay, I can see that 25 = 1 bar +18, right?
I'm understanding all the great descriptions, but trying to understand this one in particular. How do you know that 25 = 1 bar +18?
Did Crystal's explanation do the job?

We know the bars are equal. Remember when we first drew this...
the "twice as much" part.
/------/------/ Lily
/------/ Sara

So if each of those bars is equal, you can take this diagram:
/------/------/ + 18 Lily
/------/ + 25 Sara

And "chop off" the first bar from each, as Crystal put it , so what's left for each girl this:
/------/ + 18
+ 25

And you know each girl originally had the same amount. Remember the first diagram that I drew, which didn't seem too useful at the time? It is actually helping us all along the way:

Lily and Sara each had an equal amount of money at first.
/--------------------------/ Lily
/--------------------------/ Sara
So we're always building back to that one -- Lily spent 18 and had twice as much left. That has to equal Sara's spending 25 and having half as much left. Thinking back, it would probably have been better if I kept that clear along the way, like this:
/------/------/----+18--/ Lily
/------/-----------+25--/ Sara
but you never know what's going to be important!

As you can see, some of us around here enjoy checking in with our brain cells on these
Julie
Last edited by Julie in MN on Tue Oct 25, 2011 7:25 pm, edited 2 times in total.
Julie, married 29 yrs, finding our way without Shane
(http://www.CaringBridge.org/visit/ShaneHansell)
Reid (21) college student; used MFW 3rd-12th grades (2004-2014)
Alexandra (29) mother; hs from 10th grade (2002)
Travis (32) engineer; never hs
Jamie
Posts: 22
Joined: Sun Dec 14, 2008 10:04 am
Location: Montana

Re: Needing help with Math-Workbook 5A, Ex.10, #4

Thank you, thank you, thank you!! It is so helpful to walk through this! You know, I did just fine in my math classes all through school, but it was definitely not something that came naturally to me. It seemed like I always had to look back to help me remember how to do all the steps, rather than just understanding. I desire for my children to understand, and not just follow the steps that they're told. This is so much fun! I've been very pleased with Singapore. I look forward to our continued learning.

Thanks again for the great help! It is very much appreciated!!!
Jamie
Married to my sweetie for 16.5 years
14 ds, 12 dd, 10 dd, 7 ds, 4 ds, 1.5 dd
MFW K, ECC, CtG, RtR, Ex to 1850, & 14 yo currently in 1850 to Modern
Jamie
Posts: 22
Joined: Sun Dec 14, 2008 10:04 am
Location: Montana

Re: Needing help with Math-Workbook 5A, Ex.10, #4

Okay, so we did that next lesson that Crystal had mentioned from the 5A textbook.....that one problem on exercise 1D, I believe it was. Whew!! I think we ended up having to use the process of elimination.....then, I came to see how Crystal did it! I think we're getting a Singapore brain. It's good, though. I thoroughly enjoyed my son's lesson today, and the fact that he needed lots of my help. We drew lots of pictures, put down as much information as possible, then sat and stared at it until something would click in one of our brains. Thanks for the great suggestions and help.....they're coming in very useful!
Jamie
Married to my sweetie for 16.5 years
14 ds, 12 dd, 10 dd, 7 ds, 4 ds, 1.5 dd
MFW K, ECC, CtG, RtR, Ex to 1850, & 14 yo currently in 1850 to Modern
cbollin

Singapore workbook 5A exercise 29

henryteachers wrote:We are having such a hard time doing the fraction word problems in singapore workbook 5A exercise 29. Any tips on problem numbers 2-4?
You would think I could figure it out, but mama is even having trouble.
What are we in for when we hit algebra?
Thanks!
start here
http://board.mfwbooks.com/viewtopic.php?f=23&t=6838
on the thread linked above, my oldest dd, mfwstudent, wrote something for problem 2.

Problem #2

Key hint: you have to think equivalent fractions as you draw some of the bar diagrams.

You don’t know that before you start though. you have to think through and do it again. that's part of the process really.
__ __ ___ ___ ___
3 of them are morning.
2 are remaining.
Oh wait… it’s hard to see 1/4 of 2 pieces. what if we made equivalent fractions?

Go ahead and take the 3/5 and write it as 6/10. and start over. Nothing wrong with a do over.

Now, you have 10 bars all the same size.
___ __ __ __ __ __ __ __ __ __

6 of them are on the morning tarts (boy doesn’t that read weird out of context)
4 of them are remaining
1 of the 4 of them is afternoon sales.
ah ha! that's easy.

So we have
6 bars for morning__ __ ___ ___ ___ __
1 bars for afternoon __

and it tells us that 200 more were in the morning.
There are 5 more morning bars than afternoon bars.
Those 5 bars = 200
Therefore each bar = 40.

10 original bars at 40 each = 400 tarts made.