Question

52. A can do a task in 10 days and B can do the same task in 20 days. With the help of C, they is the work in 5 days. How long will it take for Calone to finish the task ?
(a) 30 days
(b) 20 days
(c) 15 days
(d) 18 days​

Answer 1

Answer:-

Given:

Amount of work completed by A in 10 days = 1

⟶ Amount of work completed by A in 1 day = (1/10).

Amount of work completed by B in 20 days = 1

⟶ Amount of work completed by B in 1 day = (1/20).

Also,

Amount of work completed by A , B & C in 5 days = 1

Amount of work completed by A , B , C in 1 day = (1/5).

Let us assume that,

Amount of work completed by C in x days = 1

⟶ Amount of work completed by C in 1 day = (1/x)

According to the question,

⟶ (1/10) + (1/20) + (1/x) = 1/5

⟶ 1/x = 1/5 - 1/10 - 1/20

⟶ 1/x = (4 - 2 - 1) / 20

⟶ 1/x = 1/20

⟶ x = 20 days

∴ C will complete the work in 20 days (Option - B).

Answer 2

Answer:

Hence, C alone take 20days to finish the task.

Step-by-step explanation:

I hope you get the answer.