Age MCQs

The age of the father 3 years ago was 7 times the age of his son. At present, the father’s age is 5 times that of his son. What are the present ages of son and father?

Solution: 
Let the present age of son = x years
Then, the present age of father = 5x years
3 years ago,
7(x – 3)= 5x – 3
Or, 7x – 21 =5x – 3
Or, 2x =18
x = 9 yrs
Therefore, son’s age = 9 years
Father’s age = 5x = 5 (9) = 45 years

Short Tricks:

Son’s age = {3*(7-1)/7-5} = 9 years
And father’s age = 9 × 5 = 45 years.

Question. 2:

At present, the age of the father is five times the age of his son. Three years hence, the father’s age would be four times that of his son. Find the present ages of the father and the son.
Solution: Let the present age of son = x years
Then, the present age of father = 5x years
3 yrs hence,
4(x+3)= 5x+3
Or, 4x + 12=5x +3
x= 9yrs.
Therefore, son’s age = 9 yrs and father’s age = 45 yrs

Short tricks :

Son’s age = {3*(4-1)/5-4} = 9yrs
father’s age = 9 × 5 =45 yrs