Question

A person crosses a 600 m long street in 5 minutes. What is his speed in km per hour?

• A. 3.6 km/hr
• B. 8.4 km/hr
• C. 18 km/hr
• D. 7.2 km/hr

Answer 1

The correct option is D

7.2 km/hr

Given,
Speed = $\frac{600}{5}$ m/min = $\frac{600}{5\times 60}$ m/sec
= 2 m/sec

We have,
$1\frac{m}{sec}=\frac{\frac{1}{1000}km}{\frac{1}{3600}hr}$

$\therefore 1\frac{m}{sec}=3.6\frac{km}{hr}$

$\therefore 2\frac{m}{sec}=2\times 3.6km/hr=7.2km/hr$