The average of 50 numbers was calculated as 38. Later it was found that two numbers were wrongly taken as 33 and 27 instead of 23 and 17. What is the correct average?
Show answer & explanation
Correct answer: C
Explanation
Given:
Number of numbers = 50
Incorrect average = 38
Incorrect numbers = 33, 27
Correct numbers = 23, 17
Incorrect total = 38 × 50 = 1900
Sum of incorrect numbers = 33 + 27 = 60
Sum of correct numbers = 23 + 17 = 40
Correct total = 1900 − 60 + 40 = 1880
Correct average = 1880 / 50 = 37.6