Question

the average age of 4sisters is 7year.if the age of mother is included the average is increased by 6years.find the age of the mother
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Answer 1

Answer:

answer is 37 years

Step-by-step explanation:

let A, B, C, D be the age of 4 sisters.

Then their average age -->

(A+B+C+D)/4=7

(A+B+C+D) = 7*4

(A+B+C+D) = 28 _____(equation -1)

now let mother's age be M

and if mother age is included in average

(A+B+C+D+M)/5 = 7+6

(A+B+C+D+M) = 13*5

(A+B+C+D+M) = 65

from equation 1 putting value

( 28) + M = 65

M = 65-28

M = 37 years