Question

A & B together do a work in 40 days. B & C together do in 25 days. A and B started working together, and A left work after 6 days & B left work after 8 days. After A left, C join the work & C completed the work in 40.5 days, C alone can complete the work in how many days?

• A. 80 days
• B. 120 days
• C. 70 days
• D. 50 days

Answer 1

Answer:

D. 50 days

Let the efficiency of C be x

Now,

6 × 5 + 2 × 8 + 38.5 × x = 200

⇒ 30 + 16 + 38.5x = 200

⇒ 38.5x = 200 - 46

⇒ 38.5x = 154

⇒ x = 4

So, the efficiency of C = 4

So, time taken by C = 200/4 = 50 days