Question

A math class is made up of 20 boys; the rest are girls. Eighty percent of the class is boys. How many students are in the math class?

Answer 1

Solve this problem by setting up a proportion to model the number of boys to the total number of students than the class:
80/100=20/x

Now, cross multiply:
80x=2000

Then, divide 2000 by 80 to solve for x:
x=25

25 is the total number students in the class.

Hope this help

Answer 2

Part- 20
Percent- 80%
Whole- ?


For 80 to get to 20 we can divide by 4

20 80
-— = -—
100
Whatever we do to the top we do to the bottom!
So we can divide 100 by 4 as well. That is 25. 20
-—
25
There are 25 students in the class.
That’s how I learned.
Hope it helped!