Question

Present age of a grandfather is $72$ years, while his grandson's age is $12$ years. After $8$ years, ratio of grandfather's age to grandson's age would be ____.

• A. 6:1
• B. 5:1
• C. 4:1
• D. 9:1

Answer 1

The correct option is C

4:1

Grandfather's present age is $72$ years.
Grandson's present age is $12$ years.

After $8$ years,
grandfather's age would be :
$72+8=80$ years
and grandson's age would be :
$12+8=20$ years.

So, after $8$ years, the ratio of grandfather's age to grandson's age would be:
$\frac{80}{20}=\frac{4}{1}=4:1$.