A alone can do a work in 20 days. A and B together can do the same work in 15 days. B and C together can do the same work in $\frac{75}{2}$ days. What is the ratio of the efficiency of A, B and in terms of doing the work?
Answer & explanation
Correct answer: option 4
A = 20 days,
A + B = 15 days,
B + C = \(\frac{75}{2}\) days,
⇒ A + B = 20
⇒ 15 + B = 20
⇒ B = 5,
Similarly,
⇒ B + C = 8
⇒ 5 + C = 8
⇒ C = 3,
Therefore efficiency ratio is,
A : B : C = 15 : 5 : 3