Question

The mean of seven numbers is 16. Six of these numbers are 12, 20, 19, 10, 21 and 13. Find the seventh the seventh number.​

Answer 1

The 7th number is 17

Explanation:

let x is the seventh number

add all the numbers and the missing number

then divide by 7

(12+ 20+ 19+ 10+ 21+13 + x)/7 = 16

(95 + x)/7 = 16

95 + x =112

x = 112 -95

x = 17