A person covers 11 km at a speed of 3 km/h, 21 km at a…

A person covers 11 km at a speed of 3 km/h, 21 km at a speed of 5 km/h and 37 km at a speed of 10 km/h. Find the average speed for the entire journey.

Show answer & explanation

Correct answer: A

Explanation

The correct answer is Option 1 i.e. $5\frac{335}{347}$ km/h

Total distance = 11 + 21 + 37 = 69 km

Time taken = $\frac{11}{3} + \frac{21}{5} + \frac{37}{10} = \frac{347}{30}$ hours

Average Speed = $\frac{69}{\frac{347}{30}} = \frac{2070}{347}$ = $5 \dfrac{335}{347}$ km/h

SSC Selection Post 2023 PYQ — Question 56