At present, the ratio of the ages of P and Q is 3 : 5, the ratio of ages of Q and R is 3 : 4 and the ratio of ages of R and S is 10 : 11. If the sum of the present ages of all of them is 198 years, what is the ratio of ages of Q and R after 15 years?
At present, the ratio of the ages of P and Q is 3 : 5, the ratio of ages of Q and R is 3 : 4 and the ratio of ages of R and S is 10 : 11. If the sum of the present ages of all of them is 198 years, what is the ratio of ages of Q and R after 15 years? Correct Answer 4 : 5
Let the present ages of P, Q, R and S be ‘p’, ‘q’, ‘r’ and ‘s’ years respectively.
p : q = 3 : 5, q : r = 3 : 4 and r : s = 10 : 11
p : q = 9 : 15 and q : r = 15 : 20
p : q : r = 9 : 15 : 20 and r : s = 20 : 22
∴ p : q : r : s = 9 : 15 : 20 : 22
Let them be 9k, 15k, 20k and 22k years respectively.
9k + 15k + 20k + 22k = 198
⇒ 66k = 198
⇒ k = 3
Present ages of Q and R is 45 years and 60 years respectively.
Ratio of their ages after 15 years = 60 : 75 = 4 : 5
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Feb 20, 2025