Solved UPSC CDS/OTA Question
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Q · Average Medium · 45s
The average age of three boys is 15 yr. If the ratio of their ages is 3 : 5 : 7, what is the age of the oldest boy?
TopicAverage
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Final Answer: Option C — 20 yr