Shobhita can complete a painting work in 20 hours while Saroj can complete the same work in 15 hours. In how much time (in hours) can the entire work of painting be completed, if both Shobhita and Saroj work simultaneously?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. .
Total work = 60 (LCM of 20 and 15)
Efficiency of Shobhita and Saroj = (60/20) + (60/15) = 3 + 4 = 7
Time required to complete the painting for both Shobhita and Saroj together = 60/7 = hours