Question

50 men can paint a building in 15 days working 4 hours a day. In how many days will 40 men working 5 hours a day complete the work?

• A. 14 days
• B. 15 days
• C. 16 days
• D. 17 days

Hint:

When adjusting work rates, maintain the total work in man-hours as constant to find the equivalent number of days or hours needed with different teams.

Answer 1

The Correct Option is B

Step 1: Calculate the total man-hours required to complete the work.
Total man-hours = number of men × number of days × hours per day \[ \text{Total man-hours} = 50 \times 15 \times 4 = 3000 \text{ man-hours} \]

Step 2: Determine how many days 40 men working 5 hours a day will take.
\[ \text{Daily man-hours with 40 men} = 40 \times 5 = 200 \text{ man-hours per day} \] \[ \text{Days required} = \frac{\text{Total man-hours}}{\text{Daily man-hours}} = \frac{3000}{200} = 15 \text{ days} \]