Question

A swimmer swims 300 m and then returns in 12 minutes. Find his speed in
(a) m/s
(b) km/h

Answer 1

distance travelled by swimmer is $300m=0.3km$

Time taken is $12min=12\times 60s=720sec=\frac{12}{60}hr=0.2hr$

$\left(a\right)$speed in $m/s=\frac{300}{720}=\frac{5}{12}m/s$

$\left(b\right)$speed in $km/hr=\frac{0.3}{0.2}=\frac{3}{2}km/hr=1.5km/hr$