Question

The arithmetic mean of 10 items is 4 and arithmetic mean of 5 items is 10 . The combined arithmetic mean is:

• A. 5
• B. 6
• C. 7
• D. 8

Answer 1

Answer:

B. 6

Arithmetic mean of 10 items is 4 Sum of 10 items = 10 × 4 = 40 Arithmetic mean of 5 items is 10 Sum of 5 items = 5 × 10 = 50 Combined arithmetic mean = (40 + 50)/(10 + 5) = 90/15 = 6