Question

Arvind is eight years older than his sister. In three years,he will be twice as old as his sister. How old are they now?

Answer 1

SISTER'S AGE=5
ARVIND'S AGE=13

Answer 2

$\bf{\huge{\underline{\boxed{\sf{\blue{Answer:}}}}}}$

Given that,

Arvind is 8 years older than his sister.

Let the present age of his sister be x.

Therefore his present age = x + 8

$\bold{According\:To\: Question:-}$

After 8 years, Arvind will be twice as old has his sister will be.

➡ (x + 8) + 3 = 2(x + 3)

➡ x + 11 = 2x + 6

➡ x - 2x = 6 - 11

➡ -x = -5

➡ x = 5

Hence, the present ages of :-

Arvind's sis = x = 5 years

Arvind = x + 8 =13 years.

$\huge{\sf{\boxed{\boxed{Verification:-}}}}$

Arvind's age must be twice as his sister's age after 8 years.

LHS :-

» 2(Arvind's sister's age after 3 years)

= 2(5 + 3)

= 2(8)

= 16 years

» Arvind's age after 3 years

= 13 + 3

= 16 years

$\bold{L.H.S=R.H.S}$