Anay does the 5/11th part of the work in 10 days and Rohan does the 5/6th of the same work in 15 days. They started together but Rohan left the work 5 days before the completion of the work and Anay completed the work. Find the number of days after which Rohan left work.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 153/20 days.
Anay does the 5/11th part of the work = 10 days
So, Anay finish the total work = 10 × 11/5 = 22 days
Rohan does the 5/6th of the same work = 15 days
So, Rohan finish the total work = 15 × 6/5 = 18 days
Let's assume the total work = LCM of 22 and 18 = 198
Efficiency of Anay = 198/22 = 9 unit per day
Efficiency of Rohit = 198/18 = 11 unit per day
So, last 5 days work of Anay = 9 × 5 = 45 unit
So, total work done by both = 198 - 45 = 153 unit
So, total time = 153/(9 + 11) = 153/20 days