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Question
It takes 120 minutes to weed a garden with 6 gardeners. If the same work is to be done in 30 minutes, how many more gardeners are needed?
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Solution
Let the, number of gardeners needed be x.
| Number of gardeners | 6 | x |
| Time in minutes | 120 | 30 |
As the number of gardeners increases the time decreases.
They are in inverse proportion,
x1y1 = x2y2
6 × 120 = x × 30
x = `(6 xx 120)/30`
x = 24
∴ To complete the work in 30 min gardeners needed = 24
Already existing gardeners = 6
∴ More gardeners needed = 24 – 6 = 18
18 more gardeners are needed
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