Multiple choice

$12$ children can complete a piece of work in $21$ days. Approximately, how many children will be required to complete the same piece of work in $15$ days?(Approximately)

  1. $24$
  2. $14$
  3. $22$
  4. $17$
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D Correct answer
Explanation

Using the inverse proportion formula (M1*D1 = M2*D2), we have 12 * 21 = M2 * 15. Solving for M2 gives (12 * 21) / 15 = 252 / 15 = 16.8. Since the number of children must be an integer, 17 is the closest approximation.

AI explanation

Using the formula that men multiplied by days is constant for a fixed amount of work, we equate 12 children multiplied by 21 days to the unknown number of children multiplied by 15 days. This gives 252 equal to 15 multiplied by the number of children. Dividing 252 by 15 results in 16.8, which means approximately 17 children are required.

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