A school has 8 periods a day each of 45 minutes duration. How long would each period be, if the school has 9 periods a day, assuming the number of school hours to be the same?
Solution and Explanation
Let the duration of each period, when there are 9 periods a day in the school, be x minutes.
The following table is obtained.
| Duration of each period (in minutes) | 45 | x |
|---|---|---|
| Number of periods | 8 | 9 |
If there is more number of periods a day in the school, then the duration of each period will be lesser.
Hence, this is a case of inverse proportion.
Therefore
\(45 × 8 = x× 9\)
\(x = \frac{45× 8}{9}\)
\(x=40\)
Hence, in this case, the duration of each period will be 40 minutes.
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