Question

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

Answer 1

LET SISTER'S PRESENT AGE BE X

THEN ARVIND'S AGE IS X+8

AFTER THREE YEARS

ARVINDS AGE=X+8+3

SISTER'S AE=X+3

AS PER THE GIVEN CONDITION

ARVINDS AGE=2*SISTER'S AGE

X+8+3=2*(X+3)

X+11=2X+6

X=5

SO SISTER'S PRESENT AGE IS 5 AND ARVIND'S PRESENT AGE IS 5+8=13