Solved UPSC CDS/OTA Question
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Q · Average Medium · 45s
3 years ago, the average family of five members was 17 years. A baby has been born; the average age of the family is the same today. Find the age of the child?
TopicAverage
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Sum of 5 members of the family at present = 17 x 5 + 3 x 5 = 100
Sum of 6 members at present (Child + All 5 family members) = 17 x 6 = 102
Age of the child (Difference) = 2 years
Final Answer: Option D — 2.5 years