Sonal, Kriti, and Priti together can complete a piece of work in 6 days, while Kriti and Priti can do the same work separately in 30 and 18 days. In how many days can Sonal alone do the same work?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 90/7 days
Given that
Kriti can do a piece of work in 30 days
Priti can do same piece of work in 18 days
Sonal, Kriti, and Priti can complete the same piece of work in 6 days
Total work = LCM (30, 18, 6) = 90 days
The efficiency of Kriti = 90/30 = 3
The efficiency of Priti = 90/18 = 5
The efficiency of Sonal = (90/6) - (3 + 5) = 15 - 8 = 7
Hence, Sonal can do the same piece of work = 90/7 days