Question

Kishan does 70% of some work in 15 days. Later, with Mahesh’s help, she completes the remaining work in 4 days. In how many days can Mahesh alone complete the entire work?
1. 42.5 days
2. 35.3 days
3. 32.6 days
4. 40.2 days
5. None of the above

Answer 1

Correct Answer - Option 2 : 35.3 days

Calculation:

Let total work be 150 units.

Since Kishan does 70% of the work (i.e. 105 units) in 15 days,

Kishan = 105/15

⇒ 7 units per day

Work left = 150 – 105

⇒ 45 units

Let Mahesh do x units of work per day. Mahesh and Kishan finish the pending work in 4 days.

∴ 4(x + 7) = 45

⇒ 4x + 28 = 45

⇒ 4x = 17

⇒ x = 4.25 units

∴ Time taken by Mahesh to complete the work = 150/4.25

⇒ 35.29 ≈ 35.3 days

Mahesh alone can complete the entire work in 35.3 days.