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Question
10 farmers can plough a field in 21 days. Find the number of days reduced if 14 farmers ploughed the same field?
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Solution
Let the required number of days if 14 farmers ploughed = x
| Number of days | 21 | x |
| Number of farmers | 10 | 14 |
As number of farmers increases, number of days decreases.
∴ They are in inverse proportion
x1y1 = x2y2
21 × 10 = x × 14
x = `(21 xx 10)/14`
x = 15
Initially the farmers worked for 21 days.
Now they worked for 15 days.
∴ The number of days reduced = 21 – 15 = 6 days
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