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:

Correct Option (1)

The total duration of the class from 11:00 am to 2:27 pm is determined as follows:

• From 11:00 am to 12:00 pm: 60 minutes
• From 12:00 pm to 2:00 pm: 120 minutes
• From 2:00 pm to 2:27 pm: 27 minutes
• Total elapsed time = 60 + 120 + 27 = 207 minutes.

There are four periods of equal duration. A rest of 5 minutes is provided after each period. For four periods, there will be three rest intervals (between period 1 and 2, period 2 and 3, and period 3 and 4).

• Total rest time = 3 intervals × 5 minutes/interval = 15 minutes.

The effective time dedicated to the periods, excluding rest intervals, is calculated as:

• Effective period time = Total elapsed time - Total rest time = 207 minutes - 15 minutes = 192 minutes.

Since there are four periods of equal duration, the duration of each period is:

• Duration of one period = Effective period time / Number of periods = $\frac{192}{4}$ = 48 minutes.

Incorrect Options:

Options 2 (50 minutes), 3 (51 minutes), and 4 (53 minutes) are incorrect. These values do not correspond to the calculated duration of 48 minutes per period when considering the total class time and the specified rest intervals. If any of these durations were accurate, the total time elapsed from 11:00 am to 2:27 pm would differ from 207 minutes.