Question

In a college, there are 10 periods per day, each of 40 minutes. The principal wants to reduce the number of periods without changing the total working hours. Find the duration of each period, if the number of periods is reduced to 8.

• A. 30 minutes
• B. 55 minutes
• C. 50 minutes
• D. 45 minutes

Answer 1

The correct option is C

50 minutes

When the number of periods is 10, time for each period is 40 mins.
Let the time for each period be y mins when the number of periods is changed to 8.

Given, total working hours is constant. As the number of periods decreases the time for each period increases.

So, they are inversely proportional.
$⟹$10 × 40 = 8 × y
$⟹$ $y=\frac{10\times 40}{8}=50\text{minutes}$.

The principal should make each period of 50 mins.