Question

Question #b6c11

Answer 1

See a solution process below{

Explanation:

Let's call the age of the younger sister: `a`

Then, the age of the older sister is: `2a`

If the sum of their ages is `12` we can write this equation and solve for `a`:

`a + 2a = 12`

`1a + 2a = 12`

`(1 + 2)a = 12`

`3a = 12`

`(3a)/color(red)(3) = 12/color(red)(3)`

`(color(red)(cancel(color(black)(3)))a)/cancel(color(red)(3)) = 4`

`a = 4`

The younger sister is: 4 years old.

The older sister is: `2 xx 4 =`8 years old.