Question

john is 7 years older than her
sister and the sum of their
ages is 21 years find the age


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Answer 1

let age of johan be x and age of johan s sister be y

A.T.Q

x = y + 7______(i)

x +y = 21

put (i)

》 y + 7 + y = 21

》 2y = 21 -7

》 2y= 14

》 y = 7

put y = 7 in (i)

x = 7 + 7

x = 14

Answer 2

Answer:

Find the age of What?

Of you want me to find John's sister's age:

Age of John =7 years

Let age of sister be =x

Sum of their ages =21

->7+x=21

->x=21-7

->x=14

Hence, Age of sister is 14 years