Need help with fractions

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esthernairn

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I need to know how to WORK this problem Out! i have the answer but i need the "work part.
The problem is this: Mrs. chen's cakes calls for 2 1/2 cups of whipped cream. Of that, 1/3 cup is saved for the topping. The rest goes into the batter. What expression could represent how much whipped cream is in the batter? The Answer is 15/6 - 2/6. How was this problem worked out?
 
Numbers were set up as a subtraction.

Mixed fractions were converted to the MUCH more useful improper fractions.

Common denominators were selected.

That's about it.

Note: It's the "working out" part that you are supposed to be learning. Knowing the answer is just a tiny part.
 
I don't mean to hijack this thread, but I figured it's a similar problem

OK, I'm helping my niece with 6th grade math where she's doing all kinds of fractional problems. All was fine until we hit one problem that just didn't look right to me. I'm now feeling it's like a conundrum and I've fallen back on Free Math Help for some hints/help. Hopefully someone can assist! Here's the problem:

It takes 1/3 of a cup of milk to make a latte. You've got 7/9 cup of milk. So, how many latte's can you make and what is left over?

We're looking at how many times 1/3 goes into 7/9. Of course, the first thing you do is match the denominator of the larger fraction, so we've now got 3/9. If you divide 7/9 by 3/9, you flip 3/9 to the reciprocal 9/3 and multiply, giving you 63/27. Now, dividing 63/27 yields 2 9/27, which is 2 1/3. All is fine, right? Well...

If you go about this with basic subtraction, you get different results. Case in point: 7/9 - 3/9 = 4/9. 4/9 - 3/9 = 1/9. So, we know 3/9 goes into 7/9 2 times (2 lattes), leaving 1/9 cup of milk left over. 2 1/9. But 2 1/9 does NOT equal 2 1/3!! So... what am I getting wrong? :confused:
 
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i am having trouble with fractions and decimals

can anyone explain how to write a decimal as a fraction in simplest form
 
Denis said:
True, 2 1/9 <> 2 1/3; but you can't compare that way;
instead: 1/9 = 1/3 of a cup; capish?
Click to expand...

Ah, I think I see what you're saying. There's the matter of the fraction of the measurement, and then there's the fraction of that's left over.

The 1/9th is NOT 1/9th of a cup, whereas the 1/3rd in the division method is 1/3rd of a cup. I was ignoring the unit of measure in context. So, in effect it's just a portion of 7/9ths, not of a whole cup. What's the most straightforward way to write the equation showing how the 1/9th equates to 1/3rd cup?
 
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i need help!!!!!!!!

i need help like NOW!! 3,389 divided by 2 and 90 divided by 6 i need help!!!!!! :( please replyy
 
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