Question

When a number x is added to the set of numbers 5, 7, 8, 12, 6, 10 and 11; the new mean is 9. Calculate the value of x.

Answer 1

Step-by-step explanation:

mean = 5+7+8+12+6+10+11+x

8

therefore, 9 = 48+x

8

therefore, 72 = 48 + x

x= 72- 48 = 24

therefore, the value of x is 24.

Answer 2

Answer:

Step-by-step explanation:

9 = 5 + 7 + 8 + 12 + 6 + 10 + 9 + 11 + x / 9

81 = 68 + x

x = 81 - 68

x = 13