Question

Jane sells 8 times as many Volvos as Melissa. If the difference in their sales is 35, how many cars did Jane sell?

Answer 1

Here we have 2 variables we need to calculate:
x - how many Volvos Jane sold
y - how many Volvos Melissa sold

We write system of equations:
x = 8*y
x - y = 35
------------
8y - y = 35
7y = 35
y = 5
x = 8*5 = 40

Jane sold 40 cars.