A and B together can complete a work in 60 minutes, while B and C take 30 minutes and C and A in 40 minutes. Find the time taken by A, B and C to complete the same work.
Answer & explanation
Correct answer: option 2
Efficiency of A + B + C = \(\frac{1}{2}\) ((A + B) + (B + C) (C + A))
= \(\frac{1}{2}\) (2 + 4 + 3) = \(\frac{9}{2}\)
Time taken by (A+ B + C) = \(\frac{Total\; work}{Efficiency}\)
= \(\frac{120\; \times \; 2}{9}\) = 26.67 minutes