The diameter of a bullock cart wheel is $$\frac{14}{11}\ m$$​. This wheel makes ten complete revolutions per minute. What will be the speed of the cart in km/h?

Correct option is D

Given:
Diameter of the bullock cart wheel = $$\frac{14}{11}$$​ meters,
Number of revolutions per minute = 10.

Formula Used:
​$$\text{Circumference} = \pi \times \text{Diameter}$$​​
Speed of the cart is calculated as:
​$$\text{Speed} = \text{Circumference} \times \text{Revolutions per minute} \times 60$$​​

Solution:
The circumference of the wheel:
​$$\text{Circumference} = \pi \times \frac{14}{11} = \frac{14\pi}{11} \text{ meters}$$​​
The speed in meters per hour is:
$$\text{Speed} = \frac{14\pi}{11} \times 10 \times 60$$

Speed =  $$\frac{14}{11}\times \frac{22}{7} \times 10 \times 60$$  = 2400 meters/ hour

​
Speed =  $$\frac{2400}{1000} = 2.4km/h$$​​