A person crosses a 500 m long street in 10 minutes. What will the person's speed be in kilometres per hour?

Correct option is B

Given

Distance = 500 m

Time = 10 minutes

Formula used

​$$Speed = \frac{Distance}{time}$$​​

Calculation

Distance =$$\frac{ 500}{1000}\ km$$​​

                = $$\frac{1}{2}\ km$$​​

Time = $$\frac{10}{60} \ hours$$​​

Speed   = 

                  $$= \frac{ \frac{1}{2}}{\frac{10}{60}}\\\ \\ = \frac{1}{2} × \frac{60}{10}\\\ \\ = 3 km/h$$​​