Question

Mark's dad is three times older than Mark. Mark's sister is 2 years younger than Mark. (3m) The sum of their ages is 48. How old are Mark, his sister, and his dad?

Answer 1

Age of Mark
`=10` years

Age of Mark's dad
`=30` years

Age of Mark's sister
`=8` years

Explanation:

Let age of Mark be
`x` years.

Mark's dad is three times older than Mark

Age of her Mark's dad
`=3x`

Mark's sister is 2 years younger than Mark

Age of Mark's sister
`=(x-2)` years

The sum of their ages is 48.

`x+3x+x-2=48\\5x-2=48\\5x=50\\x=10`

Age of Mark
`=x=10` years

Age of Mark's dad
`=3x=3(10)=30` years

Age of Mark's sister
`=x-2=10-2=8` years