9. A grandfather is ten times older than his granddaughter. He is also 54 years older than her. Find their present ages.

Let the present age of granddaughter be x years.
and the present age of grandfather = 10x years.

As per the conditions, we have

10x – x = 54

\(\Rightarrow\) 9x = 54

\(\Rightarrow\) x = 54 ÷ 9 = 6 [Transposing 9 to RHS]

Hence,we have

the present age of the granddaughter = 6 years

and the present age of grandfather = 6 × 10 = 60 years.