Question

The average of 2, 7,6,x is 5 and the average of 18,1,6,x and y is10. what is the value of y?

Answer 1

Hi Mate !!


• First Sequence :- 2 , 7 , 6 , x
Average of first sequence is :- 5


$average = \frac{sum \: of \: the \: numbers}{total \: numbers}$


$5 = \frac{2 + 7 + 6 + x}{4}$

20 = 15 + x

20 - 15 = x

5 = x ...... ( i )

____

• Second sequence :- 18 , 1 , 6 , x , y

Average of sequence :- 10


$10 = \frac{18 + 1 + 6 + x + y}{5}$

50 = 25 + 5 + y ....... [ from ( i ) ]

50 = 30 + y

50 - 30 = y.

20 = y


So, y = 20 !!