Hello Campfire I'm helping my 11 year old with her math. Having a little trouble with it my self please help!

1. estimate the product of 1/3 x 28 =

2. 10x 6/7 =

3. 2 6/7 x 3 1/4 =

Thanks so much! Ive been out of school to long to give her much help!

We have to keep it fraction form.

Khan Academy is your friend, all the way up to Calc 2:

https://www.youtube.com/watch?v=4PlkCiEXBQI

I'm a dumbass

28/3= 9 1/3

60/7= 8 4/7

20/7 x 13/4 = 260/28= 9 2/7

I know you need it in worksheet format but do not have an Internet pen and paper!

3. 2 6/7 x 3 1/4 = 20/7 x 13/4 = 260/28 = 65/7 = 9 2/7

This helps so much! thank you all for the help!

Do not suggest you go 100% with mine. It's been a while!!!

Me too.

Because it isn't in engineering units.

Makes me feel a little better that I'm not the only one that is having trouble with this.

The answer to #1 is actually "9"

She is to estimate the product, not give an exact answer. They want her to guess toward the closest round number of what one third of 28 would be.

DD, you are probably right. I read my daughters homework and I have no clue wtf they are actually looking for sometimes. The obvious answer is not always the one they want....

Ya, reducing to decimal is the practical answer but that's not what they're looking for. In my day it was finding the greatest common denominator to learn the concept of fractions. Even before calculators that didn't make much sense to me as it was slower and required more mental contortions. After looking at some Common Core stuff I have no idea what they're looking for now. Certainly it's not the practical, simple, straight-forward method.

From what little I can tell in CC math, they want students to be "taught/forced" to do the 'shortcuts' that others have always figured out on our own. For instance, in the above #1, most anyone can guess pretty close to what the actual answer will be, then if the calculated answer is not close to that you know you've done something wrong.

Or, when adding say 210 plus 493. Many people figure out the shortcuts of taking some away from one number to make it easier (subtract 10 from 210 to get 200, add the 10 to 493 to get 503, then tack the 200 back on to that for 703). CC feels compelled to teach all of those 'shortcuts' rather than allowing a student to develop them on their own.

This results in a number of unintended outcomes: students fail to learn computational math without any shortcuts, hence not understanding the precise genius of mathematics at all; the smarter students are no longer compelled to discover 'shortcuts' on their own, hence they lack discovery skills and we all may end up missing something that would have been discovered; and parents no longer understand what is going on in their child's education; hence they look stupid and the govt has to train up a child in the way he should go knowing that when he is old he will not depart from it!

Good analysis. I have described CC as trying to mandate thinking "outside the box". In doing so, they have made the kids think "inside the box" - the institutionally approved box. Your explanation is better, though. The creative aspect of solving problems is a very individual process - hence the "creativity"!

DakotaDeer, I read the OP and was formulating a response in my mind when I read your post. I could not have said it any better.

This is a symptom of the nanny state. Instead of allowing students to figure out their own shortcuts to avoid the tedium of rigorous calculations, they try to force them and as you said, the unintended consequence is that the shortcuts become tedium.

A shortcut I use for addition is adding left to right. It takes a little practice but it really speeds up addition once you get the hang of it.

DakotaDeer,

That sounds about right and more's the pity. One of the grade schools I went to was progressive (in a good way). We were first taught arithmetic the "old fashioned" way, memorize multiplication tables, flash cards, all that sort of stuff. Only then were we taught in a way that revealed the concepts behind what we were doing, known then as modern math. After that shortcuts became obvious. Dad would be amazed. Riding in the car he'd give me real world arithmetic problems (a.k.a. word problems) from work and I'd give him the answer, working the problem in my head.

Now I rely on ever-present calculators but at least I know how to structure the problem properly. This could turn into a screed against allowing children calculators.

Was a cool school. We began on French in the fourth grade.

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First problem: 1. estimate the product of 1/3 x 28 =

Multiply to get 28/3. Make it 30/3 which is obviously 10. Back off the extra 2/3 for 9 1/3. Estimate my ass, that's the correct answer.

The problem said "estimate the product". If you are going to go through that much work why are you estimating?

That always slayed me in math class. If I'm doing all of that work, I'm going to give you the full correct answer and NONE of this estimating bull $hit.

kwg

When my daughter brought home some of that estimating crap, I had the same issue. It's just as easy to get the right answer as the almost right answer.

My daughter finally got frustrated and said, "Dad, I'm not supposed to get them right!"

Bingo!