Solved UPSC CDS/OTA Question
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Q · Time and WorkMedium · 45s
A is 30% more efficient than (b) How much time will they, working together, take to complete a job which A alone could have done in 23 days?
TopicTime and Work
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.25
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Ratio of times taken by A and B = 100: 130 = 10: 13,
Suppose B takes x days to do the work.
Then, 10: 13:: 23 : x
=> x =( 23×13/ 10 )
=> x = 299 /10
A’s 1 day’s work = 1/ 23
B’s 1 days work = 10 /299
A and B together can complete the job in 13 days.
Final Answer: Option B — 13 days