The average of 20 numbers is 45. If 50% of the numbers are increased by 4 each and the remaining 50% are decreased by 6 each, what is the new average of the numbers?
Show answer & explanation
Correct answer: A
Explanation
Given:
Total numbers = 20
Average = 45
50% of the numbers increased by 4
50% of the numbers decreased by 6
Formula:
Average = Total ÷ Number
Initial total = 20 × 45 = 900
10 numbers increased by 4
Total increase = 10 × 4 = 40
10 numbers decreased by 6
Total decrease = 10 × 6 = 60
New total = 900 + 40 − 60 = 880
New average = 880 ÷ 20 = 44