Question

Disha cycles to her school at an average speed 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

Answer:

16km/hr

Step-by-step explanation:

total distance =12×5/18×20×60

=4000m or 4 km

required speed=4km/15/60. 15/60= 1 min=1/60

4×4= 16km/h

Answer 2

Answer:

16 km/hr

Step-by-step explanation:

Disha's Average Speed = 12km/hr

Time taken = 20 minutes or 20/60 = 1/3 hr

Now the time reduced = 15minutes or 15/60 = 1/4hr

let the speed be x

Here the speed vary inversely

product of speed * Time = constant

x * 1/4 = 12*1/3

x* 1/4 = 4

x= 4 * 4

x= 16

Hope this will help you