Ram can finish a work in 18 days. Shyam is twice as efficient as Ram. If both of them start the work together, how many days will it take them to finish the work?

A6 days ✓ Correct

B8 days

C9 days

D12 days

Correct answer: (A) 6 days

Explanation

Together they finish in 6 days.

Ram does 1/18 of the work per day.

Shyam is twice as efficient, so he does 2/18 = 1/9 per day.

Combined rate = 1/18 + 1/9 = 3/18 = 1/6 per day.

Time = 1 / (1/6) = 6 days.

Want more like this? Create a free account to practise a full test, track your progress, and get spaced-repetition review.