Question

7 men plough a garden in 12 hours. In how many hours will 2 men plough it?

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Answer 1

$\huge\underline\mathfrak\purple{Solution:-}$

7 men plough a garden in 12 hours

7 is inversely proportional to 1/12.

$\tt{7 = \frac{k}{12} }$

$\tt{\implies7 \times 12 = k}$

Let, 2 men can plough a garden in x hours.

2 is inversely proportional to x.

$\tt{2 = \frac{k}{x} }$

$\tt{\implies 2 \times x = k}$

Now,

$\tt{7 \times 12 = 2 \times x}$

$\tt{\implies x = \frac{7 \times \cancel{12}}{\cancel{2}} }$

$\tt{\implies x = 7 \times 6}$

$\tt{\implies 46 \: hrs}$

Hence, 2 men can plough a garden in 46 hours.