Question

A alone can do a work in 10 days and A and B together cand do it in 6 days,then B alone will do that work in how many days?​

Answer 1

Answer:

Step-by-step explanation:

A = 10 days

⇒ A + B = 20/3 days

⇒ A + B + C = 40/7 days

L.C.M. of 10, 20/3 and 40/7 is 40 (total work).

⇒ Efficiency of A = 40 ÷ 10 = 4      ---- (1)

⇒ Efficiency of A + B = 40 ÷ 20/3 = 6

⇒ Efficiency of A + B + C = 40 ÷ 40/7 = 7     ---- (2)

From (2) – (1)

⇒ Efficiency of B + C = 7 – 4 = 3

⇒ B and C together do the same piece of work = 40/3 days

∴ B and C together do the same piece of work in 40/3 days.