The ratio of ages of 2 sisters is 4:3. The older is 3 years older than the younger sister
Let the age of the younger sister be x years.
Then, the age of the older sister is (x + 3) years.
According to the given ratio,
(x + 3)/x = 4/3
3(x + 3) = 4x
3x + 9 = 4x
9 = 4x - 3x
x = 9
Therefore, the age of the younger sister is 9 years and the age of the older sister is 9 + 3 = 12 years.