Question

The average of four numbers is 97. If three of the numbers are 87 91 and 99 what is the fourth number

Answer 1

Answer is 111

97 x 4 = 388

91 + 87 + 99 = 277

388 - 277 = 111

Answer 2

111

Explanation:

Given that the average is 97:

Value 1 = 87

Value 2 = 91

Value 3 = 99

Value 4 = x

Average= sum of all numbers/total number of values

97= 87 + 91 + 99 + x / 4

97= 277 + x/ 4

97 x 4 = 277 + x

388 = 277 + x

388 - 277 = x

x = 111