Subject: General Aptitude · Chapter: Problems on Ages · Exam: 2009 · Marks: · Difficulty:
6 years ago, the ratio of the ages of Kunal and Sagar was 6 : 5. Four years hence, the ratio of their ages will be 11 : 10. What is Sagar's age at present?
(a)16 years
(b)18 years
(c)20 years
(d)Cannot be determined
(e)None of these
Answer
Answer (as printed): A
Explanation
Let the ages of Kunal and Sagar 6 years ago be $6 x$ and $5 x$ years. $$\begin{aligned} & \text { Then, } \frac{(6 x+6)+4}{(5 x+6)+4}=\frac{11}{10} \Rightarrow \frac{6 x}{5 x} \\ & \Rightarrow 10(6 x+10)=11(5 x+10) \\ & \Rightarrow 60 x+100=55 x+110 \\ & \Rightarrow 5 x=10 \\ & \Rightarrow x=2 \end{aligned}$$ Sagar's present age $=(5 x+6)$ years $=(5 \times 2+6)$ years $=16$ years.
Explanation as extracted from the printed page; notation may be imperfect.