A class starts at 11:00 am and lasts till 2:27 pm. Four periods of equal duration are held during this interval. After every period, a rest of 5 minutes is given to the students. The exact duration of each period is:
- A48 minutesCorrect
- B50 minutes
- C51 minutes
- D53 minutes
Explanation
The class starts at 11:00 am and ends at 2:27 pm. Total duration of the class = 3 hours and 27 minutes. Converting this to minutes: (3 * 60) + 27 = 180 + 27 = 207 minutes.
There are four periods of equal duration. A rest of 5 minutes is given after every period. This means there are rests after Period 1, Period 2, and Period 3. There is no rest after the fourth period as the class concludes. So, there are 3 rest periods. Total duration of rests = 3 rests * 5 minutes/rest = 15 minutes.
To find the total teaching time, subtract the total rest time from the total class duration: Total teaching time = Total class duration - Total rest duration Total teaching time = 207 minutes - 15 minutes = 192 minutes.
Since there are four periods of equal duration: Duration of each period = Total teaching time / Number of periods Duration of each period = 192 minutes / 4 periods = 48 minutes.
Therefore, the exact duration of each period is 48 minutes.
Option A) 48 minutes is correct. Option B) 50 minutes is incorrect. Option C) 51 minutes is incorrect. Option D) 53 minutes is incorrect.
The final answer is A.
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