198k views
4 votes
I need help with this math question I already solved the first question but I don't understand the second.

I need help with this math question I already solved the first question but I don-example-1
User Lenzman
by
6.8k points

1 Answer

2 votes

We can solve this question using cross multiplication,

If the number of students who sleep 6 hours a day increases by, this means we'll have a total of 6 students who sleep 6 hours a day.

We want the ratio to be same: 15%

Then we can write:


(6)/(N)=(15\%)/(100\%)

6 students are the 15%, then N students are the 100%

Now solve for N:


\begin{gathered} 6·100=15·N \\ \end{gathered}
N=(600)/(15)
N=40

The answer is 40 students are expected.

This is a reasonable answer, given that if the number of students who sleep 6 hours doubles, for the rate to remain the same, the total of students must double.

User Sekky
by
7.0k points