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Question
Forty students stay in a hostel. They had food stock for 30 days. If the students are doubled then for how many days the stock will last?
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Solution
Let the required number of days be x.
| Number of days | 30 | x |
| Number of students | 40 | Doubled = 2 × 40 = 80 |
As the number of students increases the food last for less number of days
∴ They are in inverse proportion.
x1y1 = x2y2
30 × 40 = x × 80
x = `(30 xx 40)/80`
x = 15
The food stock lasts for 15 days
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