UPSC Prelims 2022·CSAT·Quantitative Aptitude·Time and Work

24 men and 12 women can do a piece of work in 30 days. In how many days can 12 men and 24 women do the same piece of work?

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Last updated 23 May 2026, 3:31 pm IST
  1. A30 days
  2. BMore than 30 days
  3. CLess than 30 days or more than 30 days
  4. DData is inadequate to draw any conclusionCorrect

Explanation

The problem requires determining the number of days for a different combination of men and women to complete a task. Let M be the work rate of one man per day and W be the work rate of one woman per day. From the first statement: (24M + 12W) * 30 = Total Work From the second statement, we need to find the days (D) for: (12M + 24W) * D = Total Work Equating the two expressions for Total Work: (24M + 12W) * 30 = (12M + 24W) * D To solve for D, we need to know the relationship between M and W (i.e., the ratio of a man's efficiency to a woman's efficiency). The problem does not provide this information. Let's consider possible scenarios: 1. If M = W (men and women have equal efficiency): (24M + 12M) * 30 = (12M + 24M) * D (36M) * 30 = (36M) * D D = 30 days. 2. If M > W (men are more efficient than women, e.g., M = 2W): (24(2W) + 12W) * 30 = (12(2W) + 24W) * D (48W + 12W) * 30 = (24W + 24W) * D (60W) * 30 = (48W) * D 1800 = 48D D = 37.5 days (More than 30 days). 3. If W > M (women are more efficient than men, e.g., W = 2M): (24M + 12(2M)) * 30 = (12M + 24(2M)) * D (24M + 24M) * 30 = (12M + 48M) * D (48M) * 30 = (60M) * D 1440 = 60D D = 24 days (Less than 30 days). Since the number of days depends on the unknown relative efficiencies of men and women, we cannot determine a unique answer. Analysis of Options: A) 30 days: This is only one possible outcome, not universally true. B) More than 30 days: This is also only one possible outcome. C) Less than 30 days or more than 30 days: While it covers some possibilities, it doesn't account for exactly 30 days and still doesn't provide a definitive answer. D) Data is inadequate to draw any conclusion: This is correct because without the ratio of efficiencies between men and women, a specific number of days cannot be calculated.
Quantitative Aptitude: 24 men and 12 women can do a piece of work in 30 days. In how many days can 12 men and 24 women do the same piece of wor

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