Caitlyn sold 7cars per week for the first three weeks, but in week four she sold 11 cars. What is her average number of sales per week in her first four week on the job?

A) 7
B) 8
C) 9
D) 11
E) 12

Please explain! Thanks!

2 answers

7 + 7 + 7 + 11 = 32

32/4 = ?

http://www.mathsisfun.com/mean.html
Three weeks is 7*3= 21 cars
In week four is 11* 1 = 11 cars
Add/n
(21+11)/4
32/4 = 8