Question

the mean of the eight observation is 18.75 . if seven of them are 26, 14, x ,25, 15, 13, 27, 18. find the value of x

Answer 1

Find the sum of the 8 observations:

Mean of the 8 observations = 18.75

Sum of the 8 observations = 18.75 x 8 = 150

.

Find the sum of the 7 known observations:

Sum of the 7 of them = 26 + 14 + 25 + 15 + 13 + 27 + 18 = 138

.

Find the value of x:

x = 150 -138 = 12

.

Answer: The value of x is 12

Answer 2

sum of total =8×18.75=150
26+14+x+25+15+13+27+18=150
x+138=150
x=12