Question

The average of 10 numbers is 82. If the average of first 9 of them is 72, find the 10th number.

Answer 1

Step-by-step explanation:

Let sum of first 9 nos. be by x and 10th no. be y

ATQ

(x+y)/10 = 82

x + y = 820 ----- (1)

x/9 = 72

x = 72*9

Put in (1)

y = 820 - 648

y = 172