Excluding stoppages, the speed of a bus is 152 km/hr. and including stoppages, it is 114 km/hr. For how many minutes does the bus stop per hour?

Correct option is A

Given:

Speed of the bus excluding stoppages = 152 km/hr.

Speed of the bus including stoppages = 114 km/hr.

Formula Used:

Speed loss due to stoppages = Speed excluding stoppages - Speed including stoppages

Time lost = $$\frac{\text{Speed loss}}{\text{Speed excluding stoppages}} \times 60$$ Minutes​

Time lost = $$\frac{\text{Speed excluding stoppages} - \text{Speed including stoppages}}{\text{Speed excluding stoppages}} \times 60$$ Minutes​

Solution:

Speed loss = $$152 \, \text{km/hr} - 114 \, \text{km/hr} = 38 \, \text{km/hr}$$​​

Time lost = $$\frac{38}{152} \times 60 = \frac{1}{4} \times 60 = 15 \, \text{minutes}$$​​

Thus, the correct option is (a) 15 minutes