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# Math problems - what doesn't she understand?

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I am trying to figure out what problem my daughter has with math. She is almost 8 and in the third grade. Today she was doing a math problem where she was supposed to subtract something from a given number, and then divide the result by 3. It was a Singapore word problem from textbook 3A. The problem also had the bar diagram ready. So she got the right answer, and wrote it in the rectangle on the diagram. Then I asked her to write down what she did to get the answer and she just couldn't do it. She just looked at the diagram and said something like 'it is 47 here, 20 here, so there should be 27 here, so it will be 9 there'. But she couldn't write it down as 47-20=27, 27/3=9. I asked her what would she do if we had 4 digit numbers in the problem, and she said she didn't know. She does not usually have troubles with solving the problems, but when it comes to explanations, she just looks like she doesn't know what I am talking about. Or she can solve the problem mentally, but if I ask her to draw the diagram she just stares at me. I just cannot figure out what it is that she doesn't understand. :banghead: It is like she sees the whole picture and splits the numbers her own way, but doesn't understands why? But then how can it be possible?

If it matters, I just took her out of school, where they used Everyday Math. Do they teach them to guess what number you have to add, instead of using subtraction?

I am just desperate, and maybe since I had my first problem with not understanding math at the first attempt somewhere in calculus, I just don't know what she may not understand and how to fix it. Please, help me.

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Did you do the singapore placement test before placing her in 3? Singapore is advanced vs most, and from what I hear Everyday math does not do well at preparing kids for the "how to". I would do this placement test and if she places lower, do not worry. Many people use it a level or a half level behind!

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It is possible that she understands the math intuitively and just hasn't come to the place where she has the words to explain it. If she can accurately repeat what she is doing, I'd not worry too much about it. It might help if sometimes you model the thought process for her so she can start figuring out how to explain what you do.

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I am trying to figure out what problem my daughter has with math. She is almost 8 and in the third grade. Today she was doing a math problem where she was supposed to subtract something from a given number, and then divide the result by 3. It was a Singapore word problem from textbook 3A. The problem also had the bar diagram ready. So she got the right answer, and wrote it in the rectangle on the diagram. Then I asked her to write down what she did to get the answer and she just couldn't do it. She just looked at the diagram and said something like 'it is 47 here, 20 here, so there should be 27 here, so it will be 9 there'. But she couldn't write it down as 47-20=27, 27/3=9. I asked her what would she do if we had 4 digit numbers in the problem, and she said she didn't know. She does not usually have troubles with solving the problems, but when it comes to explanations, she just looks like she doesn't know what I am talking about. Or she can solve the problem mentally, but if I ask her to draw the diagram she just stares at me. I just cannot figure out what it is that she doesn't understand. :banghead: It is like she sees the whole picture and splits the numbers her own way, but doesn't understands why? But then how can it be possible?

If it matters, I just took her out of school, where they used Everyday Math. Do they teach them to guess what number you have to add, instead of using subtraction?

I am just desperate, and maybe since I had my first problem with not understanding math at the first attempt somewhere in calculus, I just don't know what she may not understand and how to fix it. Please, help me.

It sounds to me like she knew what to do but didn't understand how to put it into words or how to write it. I would simply talk her through it.

"Good, you understood that you needed 27 here since the other two numbers were 47 and 20. We would write that 47-20=27. Does that make sense? Then, do you know what you did to the 27 to get 9? You divided by 3--we would write that, 27/3 = 9."

Start where she is and give her the words and show her how to write equations. Then gradually ask more questions and see if she can do pieces of this on her own. Try to keep the conversation affirming and positive. She is very young both for 3rd grade and for Singapore 3--all the more reason to help her by walking through this with her. HTH! Merry :-)

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It is possible that she understands the math intuitively and just hasn't come to the place where she has the words to explain it. If she can accurately repeat what she is doing, I'd not worry too much about it. It might help if sometimes you model the thought process for her so she can start figuring out how to explain what you do.

:iagree: My ds is like this sometimes. I just model the steps that we would write out. It can be really hard for some kids who do understand the math more intuitively to put it into words sometimes. If she can consistently solve that type of problem written different ways, then she clearly understands it at some level. The ability to explain it will come with time.

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Or she can solve the problem mentally, but if I ask her to draw the diagram she just stares at me. I just cannot figure out what it is that she doesn't understand. :banghead: It is like she sees the whole picture and splits the numbers her own way, but doesn't understands why? But then how can it be possible?

I'm doing 3A, and I've found that my son lacks the language to explain it to me. When I get to this situation, I go back to similar problems in the CWP book (usually of the year before) and get smaller and simpler numbers to work with, and teach him the language (again) of a problem.

While reading an Israeli book on math for parents (for sale on the Singapore website), he had a paragraph entitled "Ask me a simpler question" (it was a quote from his daughter). So, if kiddo can't explain it to me, I back up. "Well, how did you get this number?" If he gets the point across, clumsily, or a technical word wrong, I repeat his explanation in a standard nomenclature I've been using all along. E.g., I might say "so, this number is the difference between 68 and 57?" and if he is blank, I'll back up to "is this number the result of 68 minus 57?". If we are having a difficult day, I might write out the sentence in code (68-57=11), then in actual English (sixty-eight minus fifty-seven equals eleven) and then the number bond!

Some days he's like an idiot savant, and other days I feel like we are working on 2+2 is 4.

Recently, in 3A, I moved back to starting the i-excel FanMath books, from the very beginning up, making the diagrams as we went. This was, for us, a WORTHwhile diversion, and story problems are less painful now. There was a recent thread, one I started, on people's secrets for word problems. That was helpful, too.

Another thing I'm introducing is the old saw (from chemistry class) "Units are your friends". Thus 3( 68-57) + 57 (from a question such as "68 children when to the library. 57 took home one book each, the rest took home three each. How many books did the children checkout altogether).

I ask him to find me the indicator words ("altogether") and underline the pertinent bits of info (57 took home one each or "the rest took home three"). Then we talk units.

57 children X 1 book/child (and you then cross out the children and child as you do in differential analysis) and you are left with 57 BOOKS. Then you subtract 57 children from 68 children and you are left with 11 children. 11 children X 3 books/child gives you 33 BOOKS. You can then add like units: books+books= number of books altogether. If you child can identify the UNITS of the numbers in the story problems, she is on the road to knowing why she got where she did.

HTH, boy was that a mess, it's late, ask me if anything isn't clear, exit stage right.....

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I agree - she probably doesn't understand the structure in which to explain it to you. I would also suggest modeling the process for her - but be aware you may have to do so a lot for a while, or it may come up at random times.

Also, some kids approach math intuitively - they "see" the answer right away, and it comes so quickly to them that they're honestly not sure how they got there. They're working through the process, just doing so extremely quickly. My son is one of those, and is just now (halfway through Algebra 1) getting to the point where he needs to slow down and analyze his steps with word problems. Up until now, he could look at a paragraph-long problem, think for about 5-10 seconds, and come up with the answer. When asked how, he was at a loss to explain.

What I've taken to doing with him is letting him work some out in his head, but requiring him to work anything on paper that he can't just come up with an answer for on the spot. This is helping a lot - allowing him some freedom, but showing him where and why he'll need to slow down and work it through.

You wouldn't believe how many times in the past week or two I've given him a problem to solve...with the express directions of "use algebra to do so" ;) For some kids, it's a "putting it into words" issue, and for others, it's just plain the intuitive, coming up with it so fast that the steps are hard to analyze issue.

Hope that helps :)

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Thanks, it does have me a lot to think about. She definitely can do this level of work, I made her take the placement test, and she did about 85% correct, and most mistakes were just lack of attention.

However, I think there is more to it, then just inability to articulate, although it may also be part of the problem. It looks like she is actually doing it backwards. So when she looks at \$47 total, and \$20 that remained, she doesn't subtract, she chooses a number that together with 20 will give her 47. Although she obviously learned that if she is asked how much more, she will subtract. And now I see the same thing with multiplication/division. It is not 9 because 27/3=9, but because 3*9=27. It works with smaller numbers, obviously, but will not work if we have larger numbers, and especially when we come to algebra.

While she was in school, I mostly worked on math facts with her, and we did more logical type problems, which she loves and is good at, and this just fell through cracks.

OK, I guess I'll just continue doing word problems with her explaining and articulating as we go.

And kalanamak, I actually thought about bringing up units yesterday, but then decided to wait a little. It does come useful in more complex problems. I learned it in physics though :)

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It looks like she is actually doing it backwards. So when she looks at \$47 total, and \$20 that remained, she doesn't subtract, she chooses a number that together with 20 will give her 47.

That is very likely what she is doing. It is, of course, an entirely valid way to compute the missing "part" when the whole and one part are known. I know that "we" might be wishing them to be doing subtraction, but a mind trained on seeing wholes and parts (as number bonds) might easily see the "difference" between 47 and 29 being 27. But this is a skill we are training them to have by using Singapore Math. It is not all together unexpected (far to the contrary), is a skill could very well be seen as a "positive" unless she is always avoiding subtraction as a procedure.

I would also walk it through with her. What is the whole? 47. What is one part? 20? How do we find the difference? If she is "adding" you can find out then, I think it is likely. But you can make sure she know if we have the whole and one part we find the "difference" (and thereby the "other" part) by subtracting the known part from the whole.

OK, I guess I'll just continue doing word problems with her explaining and articulating as we go.

This is the best thing you can do.

Bill

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