Answer: 28
Explanation:
Five seventh is written as 5/7.
Let the total number of students in the class be represented as N.
Therefore;
5/7 * N = 20 ( This is an expression for the number of girls in the class)
Simplifying for N gives us the total number of students in the class.
5/7 * N = 20
Cross multiply
5*N = 7*20
5N = 140
N = 140 / 5
N = 28
Total number of students equals to 28