Question

disha cycles to her school at an average speed of 12 km / hrs.it takes her 20 min to reach the .if she wants to reach her school in 15 min , what should be her average speed?

Answer 1

Speed of disha = 12 km/h or 10/3 m/s
time taken = 20 min or 20×60 sec.
So distance = speed × time
= (10×20×60)/3 = 4000m

Now
Time to reach school is 15 min or 15×60 sec.
Distance is 4000m
so speed = Distance/time
= 4000/(15×60)
4000/900
= 4.44... m/s