Question

average of five numbers is 8.four numbers are 11,10,7 and 4.what is the 5th number.

Answer 1

Find the sum of the 5 numbers:

Average of the 5 numbers = 8

Sum of the 5 numbers = 5 x 8 = 40

Sum of the 4 numbers:

Sum of the 4 numbers = 11 + 10 + 7 + 4 = 32

Find the 5th number:

5th number = 40 - 32 = 8

Answer: The 5th number is 8

Answer 2

Hey dear

Given :-
Average of 5 numbers = 8

5th number = x

As we know the formula,

$average \: = \frac{sum \: of \: all \: numbers}{total \: numbers} \\ 8 = \frac{11 + 10 + 7 + 4 + x}{5} \\ 8 \times 5 = 32 + x \\ 40 = 32 + x \\ x = 8$

The fifth number is 8

Hope this helps you.