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Question
In a school there is 7 periods a day each of 45 minutes duration. How long each period is if the school has 9 periods a day assuming the number of hours to be the same?
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Solution
Number of periods increases as duration decreases, since the number of hours is same.
Let the duration of each period be x.
| Number of periods | 7 | 9 |
| Duration of period (min) | 45 | x |
x1y1 = x2y2
7 × 45 = 9 × x
x = `(7 xx 45)/9`
x = 35
Duration of every period = 35 min
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