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Question
Five workers take 12 days to weed a field. How many days would 6 workers take? How many would 15 take?
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Solution
Let us suppose 6 workers will take x days to weed a field.
As the number of workers increases, the number of days decreases.
So, the number of workers and number of days are in inverse proportion.
∴ 5 × 12 = 6 × x
⇒ x = `60/6`
⇒ x = 10 days
Let us suppose 15 workers will take y days to weed a field.
∴ 5 × 12 = 15 × y
⇒ y = `60/15`
⇒ y = 4 days
Hence, 6 workers will take 10 days, while 15 workers will take 4 days to weed a field.
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