Multiple choice

10 women can complete a work in 7 days and 10 children take 14 days to complete the work. How many days will 5 women and 10 children take to complete the work?

  1. 5

  2. 6

  3. 7

  4. 8

  5. 9
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

10 women = 7 days, so 1 woman = 70 days. 10 children = 14 days, so 1 child = 140 days. 5 women = 1/14 work/day, 10 children = 1/14 work/day. Total = 1/14 + 1/14 = 2/14 = 1/7. Days = 7.

AI explanation

Let the total work be the least common multiple of 7 and 14, which is 14 units. Since 10 women complete the work in 7 days, 10 women have an efficiency of 2 units per day. Since 10 children complete the work in 14 days, 10 children have an efficiency of 1 unit per day. Working together, 5 women and 10 children have a combined efficiency of 2 units per day, so they complete the 14 units in 7 days.

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