New RBI Grade B 2024 Batch 7 45+ 20 Days Study Plan; Download Now !!!
Register

Question

A and B together, B and C together and A and C together can complete a piece of work in 18 days, 15 days and 10 days respectively. Find the ratio of the efficiencies of A, B and C, respectively.

A 4:5:7 Correct Answer Incorrect Answer
B 5:6:6 Correct Answer Incorrect Answer
C 4:1:5 Correct Answer Incorrect Answer
D 7:5:4 Correct Answer Incorrect Answer
E 4:2:7 Correct Answer Incorrect Answer

Solution

Let, the total work be 90 units (LCM of 18, 15 and 10)
Amount of work done by A and B together in one day = 90/18 = 5 units
Amount of work done by B and C together in one day = 90/15 = 6 units
Amount of work done by A and C together in one day = 90/10 = 9 units
Amount of work done by A, B and C together in one day = (5 + 6 + 9)/2 = 10 units
Amount of work done by A alone in one day = 10 – 6 = 4 units
Amount of work done by B alone in one day = 10 – 9 = 1 units
Amount of work done by C alone in one day = 10 – 5 = 5 units
So the desired ratio = 4:1:5

Practice Next

Relevant for Exams:

×
×