The ratio of the ages of the father and the son at present is 7 : After 4 years the ratio will become 4 : 1, what is the sum of the present ages of the father and the son ?

March 5, 2024 by rawan239

will be 4:1. This means that $f + 4 = 4(s + 4)$. Substituting in the first equation, we get $7s + 4 = 4(s + 4)$. Simplifying, we get $3s = 8$. Dividing both sides by 3, we get $s = 8/3$. Substituting this into the first equation, we get $f = 7(8/3) = 28$. Therefore, the sum of their present ages is $f + s = 28 + 8/3 = \boxed{29}$ years.

Option (a) is incorrect because $32$ is not a factor of $28$. Option (b) is incorrect because $35$ is not a factor of $28$. Option (d) is incorrect because $38$ is not a factor of $28$.