Question

The mean of 5 observations is 8, and mean of 4 observations is 7, then find 5th observation

Answer 1

Let the 5th term be x

Mean of 4 observations = 7 = 28/4

Sum of 4 observations = 28

Sum of 5 observations = 28 + x

Mean of 5 observations = (28+x) / 5

(28+x) / 5 = 8

28+x = 8×5

28+x = 40

x = 40-28

x = 12

Therefore, 5th observation = 12

Hope this helps you :)