Solved UPSC CDS/OTA Question
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Q · AgeDifficult · 45s
Five years ago, the ratio of the ages of A and B was 9:7. Ten years hence, the ratio will be 11:9. Find their present ages.
TopicAge
Question Typemultiple choice
DifficultyDifficult
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained - no skipped algebra.
Let present = 9x+5, 7x+5 ⇒ (9x+15)/(7x+15) = 11/9 ⇒ solve ⇒ x=5 ⇒ A=50, B=40.
Final Answer: Option A - 50, 40