Question

pls solve this problem​

Answer 1

Answer:

32 kmph

Explanation:

let t,3t,t(all in hour) be the time taken for the 3 stages.

in 1 st case v=at

==>at= 40 kmph

now distance covered s1, s2, s3

s1= 1/2at^2 and s3=1/2at^2

but s3= 3t* 40=120 t km

hence total distance=at^2+120t

time taken (total) =t+3t+t=5t

hence average speed= at^2+120t/5t

cancelling t we have at+ 120/5=40+120/5

=160/5=32 kmph

Answer 2

thank my answer...............