Solved UPSC CDS/OTA Question
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Q · Average Medium · 45s
The average age of 30 students of a class is 14 years 4 months, due to admission of 5 new students the average becomes 13 years 9 months, while the age of the younger one in new 5 students in 9 years 11 months. Find the average of the remaining four new students?
TopicAverage
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Sum of 30 students = 30 X (43/3) = 430
Due to admission of 5 new students, Sum of 35 students = 35 X (55/4) = 481.25
Sum of ages of the 5 new members =
481.25 - 430 = 51.25
Age of younger one + Sum of the remaining 4 students = 51.25
9.916 + Sum of the remaining 4 students = 51.25Average of 4 students = 41.334/4 = 10.34
Final Answer: Option D — 10.1