Question

14. A person covers 60 km from P to Q at speed of 20 km/hr and returns from Q to P at
speed of 30 km/hr. Find the average speed of person.
a. 22 km/hr
b. 24 km/hr
c. 26 km/hr
d. 28.2 km/hr e. None of these​

Answer 1

Answer:

48km/h

Step-by-step explanation:

total distance = 2pq

speed = distance/time ➡ time = distance/speed.

time taken for pq while going is pq/40.

New speed = (40+50%×40) = (40+20) = (60).

time taken for q to p is pq/60.

Average speed = total distance/total time.

= 2pq/( pq/40 + pq/60)

= 48 kmph

Answer 2

Answer:

48 km /h

Step-by-step explanation:

Total distance=2pq

speed=d/t time=d/s

time time taken for p q while going on PQ/40

Now speed =(40+50÷*40)=(40+20)=(60)

time taken for q to p=pq/60

Average speed=total distance/total time

2pq/(pq/40+pq/60)

48kmph