Question

The first half of total distance of 50 km is covered in 2 hours, and the second half in 3 hours. The average speed is ______.

Answer 1

Given:
The total distance, $d=50\text{km}$
Total time, $T=2h+3h=5h$

Average speed, $v_{avg}=\frac{d}{T}=\frac{50\text{km}}{5\text{h}}$
$⟹v_{avg}=10\text{kmph}$ (1 marks)

Also $1km=1000m$, $1\text{h}=60\text{min}=3600\text{s}$
$⟹10\text{kmph}=\frac{10\times 1000}{3600}\text{m/s}{}^{}$
$=\frac{25}{9}\text{m/s}{}^{}=2.78m/s{}^{}$
Average speed = 2.78 m/s (1 marks)