Question

Shalu cycles to her school at an average of $12$ km/hr. It takes her $20$ minutes to reach the school. If she wants to reach her school in $15$ minutes, what should be her average speed?

Answer 1

$Speed=\frac{Distance}{Time}$
$\Rightarrow Distance=Speed\times Time$

So, distance to the school $=12km/hr\times 20minutes=12km/hr\times \frac{20}{60}hour=4$ km
So, to cover distance $4km$ in $15$minutes,

$Speed=\frac{4km}{15min}=\frac{4km}{\left(\frac{15}{60}\right)hour}=16km/hr$