The average (arithmetic mean) of 20, 40, and 60 is 5 more than the average of 10, 80, and what number?
Choose the correct choice from the following answers:
A) 35
B) 30
C) 25
D) 20
E) 15

Rationale: a 1 = 120 / 3 = 40 a 2 = a 1 - 5 = 35 sum of second list = 35 * 3 = 105 therefore the number = 105 - 90 = 15 e
Answer: E