Akash travels the distance from his home to school in three equal parts on his bicycle at a speed of 5 km/h, 10 km/h and 15 km/h, respectively. What is the average speed of Akash going from his home to school?

Correct option is C

Given:
Distance from home to school is divided into 3 equal parts.
Speeds: 5 km/h, 10 km/h, 15 km/h respectively.
Formula Used:
​$$\text{Average Speed} = \dfrac{\text{Total Distance}}{\text{Total Time}}$$​​
Solution:
Let the total distance from his home to school = 3x
​$$\text{Average speed} = \dfrac{3x}{\dfrac{x}{5} + \dfrac{x}{10} + \dfrac{x}{15}} \\[8pt]= \dfrac{3}{\dfrac{6 + 3 + 2}{30}} = \dfrac{3 \times 30}{11} = \dfrac{90}{11} \approx 8 \tfrac{2}{11} \ \text{km/h}$$​​