Question

pls do this problem.....

Answer 1

in firat case
distance=30km
speed = 40km/h
time = distance /speed
time = 30/40
time = 3/4h
..
in second case
distance = 50km
speed = 20km/h
time = distance /speed
time = 50/20
time =5/2h
...
total distance=30+50=80km
total time = 3/4+5/2= 3.25h
...
average speed = toatal distance /totaltime
average speed= 80/3.25
average speed =24.61km/h

Answer 2

Average speed = total distance / total time

=)) 30km+50km(t¹+t²)
.
[80km/(30km/40km+50km/20km)]

=))[80km/(3/4h+5/2h)]


[80/(3/4+10/4)h]

[80/13/4]

=80*4/13

=))320/13

=24.61....