Solved UPSC CDS/OTA Question
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Q · Average Medium · 45s
There are 42 students in a hostel, due to the admission of 13 new students, the expenses of the mess increased by rupees 30 per day, while per day expenditure per student is reduced by rupees 3. What was the original expenditure of the mess per day?
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.
Let the earlier average was A rupees/ day/student
So, the total was 42A
New number of students = 55
Now the new total will be 55 (A – 3)
So, 42A + 30 = 55 (A – 3) A = 15
Original expense of mess = 42A
= 42 x 15 = 630
Final Answer: Option A — 420 rupees