Question

Father is $3$ yr older than the mother and the mother's age is now twice the daughter's age. If the daughter is $20$ yr old now, then the father's age when the daughter was born.

• A. $20$ yr
• B. $40$ yr
• C. $43$ yr
• D. $23$ yr

Answer 1

The correct option is D $23$ yr

Let the age of the father be $F$, age of mother be $M$ and the age of their daughter is $D$.

It is given that the age of the daughter is $20$ years old, that means $D=20$. Also, mother's age is twice the daughter's age that is:

$M=2D=2\times 20=40$

Thus, the age of mother is $40$ years.

Now, father's age is $3$ year older than the mother, that is:

$F=40+3=43$

Therefore, the father’s age is $43$ years and his age when her daughter was born is:

$43-20=23$ years. (As her daughter's age is $20$ years)

Hence, the father's age when the daughter was born is $23$ years.