Grandsons age = 9 years!

Grandfather's age = 72 years!

Explanation :-

If current year of grandson's considered = X Then, Grandfather's age = 8X

Grandfather 63 years older than grandson.

( Given in question )

→ X + 63 = 8X

→ 8X - X = 63

→ 7X = 63

→ X = 63 ÷ 7

→ X = 9.

8X = 8 × 9

= 72.

Therefore

Grandsons age = 9 years.

And

Grandfather's age = 72 years.

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