s is being multiplied by 3/7.
You want s alone, which is the same as s being multiplied by 1.
Multiply 3/7 by its reciprocal, 7/3, to get 1.
You must multiply both sides of an equation by the same number, so multiply both sides of the equation by 7/3.
3/7 s = 6
(7/3)(3/7) s = 7/3 * 6
s = 7/3 * 6/1
s = 42/3
s = 14
There are 14 students in the class.
