pzazz12 wrote:

In a small snack shop, the average (arithmetic mean) revenue was $400 per day over a 10-day period. During this period, if the average daily revenue was $360 for the first 6 days,what was the average daily revenue for the last 4 days?

A. $420

B. $440

C. $450

D. $460

E. $480

Avg(10 days) = (Avg(6 days)*6 + Avg(4 days)*4)/10

10*$400 = 6*$360 + 4*x

x+6*90=1000

x=460

Answer is (D) _________________

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