The average of 4 numbers is 25. If three of the numbers are 20, 28, and 32, what is the fourth number?
Show answer & explanation
Correct answer: A
Explanation
Given:
Average of 4 numbers = 25
Three numbers = 20, 28, 32
Formula:
Average = (Sum of numbers) / (Number of numbers)
Total = 25 × 4 = 100
Sum of three numbers = 20 + 28 + 32 = 80
Fourth number = 100 − 80 = 20