Question

The students in a political science class are divided up into three categories: liberal,
conservative, or moderate. There are five more conservatives than moderates, and twice as
many liberals as conservatives. How many of each type are there if there is a total of 87
students in the class?

Answer 1

just put the words into symbols. If the numbers are x,y,z, respectively, then we are told that

y=z+5
x=2y
x+y+z=87

Now just solve the equations.

Answer 2

Let m represent the moderates.

m + m + 5 + 2(m + 5) = 87

4m + 15 = 87

4m = 72

m = 18