The average of 21 numbers is 44. The average of first 11 numbers is 48 and that of last 11 numbers is 42. If 11th number is excluded, What is the average of the remaining numbers?
Answer & explanation
Correct answer: option 3
Sum of 21 numbers = 21 × 44 = 924
Sum of first 11 numbers = 11 × 48 = 528
Sum of last 11 numbers = 11 × 42 = 462
11th number = 924 - ( 528+462) = 66
After excluding 11th number
New average = \(\frac{858}{20}\) = 42.9