X and Y can complete a work in 9 days and 36 days, respectively. X begins to do the work, and they work alternately, one at a time, for one day each. The whole work will be completed in:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e.
Given that
X and Y can complete a work in 9 days and 36 days, respectively.
X begins to do the work, and they work alternately
According to the question
X × 9 = Y × 36
X/Y = 4/1
Total work = 4 × 9 = 36
In 2 days, (4 + 1 = 5) work will be completed
In 14 days, 35 work will be completed
The remaining (36 - 35 = 1) work will be completed in 1/4 days
Hence, The whole work will be completed in