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3 votes
3 votes
You are assigned 32 math exercises for homework. You complete 87.5% of these before dinner. How many do you have left to do after dinner?

How Many problems Are left

User Skaqqs
by
2.7k points

2 Answers

6 votes
6 votes
87.5% as a decimal is .875
.875 times 32 is 28.
multiplying the decimal by the number is saying how many of this number
32-28 is 4.
There are 4 homework assignments left to do after dinner
User Grant Miller
by
3.0k points
4 votes
4 votes

Answer:

4 problems

Explanation:

(I'm going to type a lot, but it isn't at all hard when you really understand and get the hang of it) If you are assigned 32 math exercises for homework and you complete 87.5% of them, this means that the problem is not asking for 87.5 % of 32, but what is left after you finish 87.5%, which means we should subtract 87.5 from 100. 100-87.5=12.5. 12.5% now represents the percent of the 32 original questions we have left to do after dinner. So, now we need to create a proportion. 12.5% means 12.5% out of 100%, with the 100% meaning 32, because that is the total amount of questions we have. so, this means we have
(12.5)/(100). To use this to solve our problem, we have to act as if the 32 also represents 100%. So, we have to multiply this fraction (
(12.5)/(100)) by
(x)/(32) so that the 12.5% out of 100 lets us see how many problems 12.5% out of 100% would represents the remaining questions out of 32. so, we would solve for x (x representing the questions left to do after dinner.) So, we would form this equation and solve for x. -->
(12.5)/(100) =(x)/(32). Now, we would cross multiply, then divide. So we would first multiply 12.5 times 32. This would give us 400. Then, we divide 400 by the 100, which gives us 4, which means that we have 4 problems left to do after dinner.

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