The average (arithmetic mean) of 20, 40, and 60 is 5 more than the average of 10, 50, and what number?  Select the correct option:  A) 40  B) 45  C) 55  D) 45  E) 50

Rationale: "a 1 = 120 / 3 = 40 a 2 = a 1 - 5 = 35 sum of second list = 35 * 3 = 105 therefore the number = 105 - 60 = 45 d"
Answer: D