Question

Monica earned $18.50, $23.00, and $15.00 mowing lawns for 3 consecutive weeks She wanted to earn an average of at least $18 per week. What is the minimum she should earn during the 4th week to meet her goal?

Answer 1

Add the four weeks of earnings, divide them by four and this equals the average of $18 per week.

x= fourth week earnings

18= ($18.50 + $23 + $15 + x)/4
multiply both sides by 4
72= 56.50 + x
subtract both sides by 56.50
15.50= x

ANSWER: She must earn $15.50 the fourth week to average $18 per week.