Question

Suppose that you work part-time as a sales representative at a car dealership. You earn a base salary of $125 per week plus a 18% commission on all sales that you make. Your best friend has exactly the same job at another car dealership but earning a base salary of 85$ per week plus a 21% commission on all sales. How much do you and your friend need to sell in order to earn the same amount in any given week?

Answer 1

Define the two friends as person A and person B.

Let x =  the sales in a week.

Person A:
$125 per week plus 18% commission on sales.
Earnings in a week on x sales is
125 + 0.18x

Person B:
$85 per week plus 21% commission on sales.
Earnings in a week on x sales is
85 + 0.21x

For the two earnings to be equal,
85 + 0.21x = 125 + 0.18x
0.03x = 40
x = 40/0.03 = $1333.33

Answer: $1,333.33