If the average (arithmetic mean) of a series of numbers is 20 and their sum is 160, how many numbers are in the series?
A. Negative And Greater Than -1.
B. Negative And Less Than -1.
C. A Positive Fraction Greater Than 1.
D. Positive And Less Than 1.
E. 1 And Only 1.
In order to raise money for a class trip, Claudia sells ice cream bars at a high school basketball game. Her profit function is P(X) =$1.25x - $12, where x represents the number of ice cream bars sold. How many ice cream bars would she need to sell in order to raise $78 for the trip?