Multiple choice

5 men or 7 women can do a piece of work in 28 days. find the time required by 7 men and 5 women to complete the task?

  1. 9 days

  2. 13 days

  3. 11 days

  4. 12 days

  5. 10 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

5 men = 7 women. So 1 man = 7/5 women. 7 men + 5 women = 7(7/5) + 5 = 49/5 + 25/5 = 74/5 women. Using M1D1 = M2D2: 7 women * 28 days = (74/5) women * D2. D2 = (7 * 28 * 5) / 74 = 980 / 74 = 13.24 days. The closest integer is 13.

AI explanation

Using the man-days equivalence formula, 5 men equal 7 women in capacity, meaning 1 man = 7/5 women. To find the individual capacity, the total work is 5 men * 28 days = 140 man-days, which is also 7 women * 28 days = 196 woman-days. The team of 7 men and 5 women is equivalent to (7 * 7/5) + 5 = 49/5 + 25/5 = 74/5 women. Dividing the total work of 196 woman-days by this team capacity of 74/5 gives 196 * 5 / 74 = 980 / 74 days. This calculates to approximately 13.24 days, meaning the closest and correct answer is 13 days.

Keep practicing — related questions