Question

a plane flies a distance 1/4 th of the total distance with speed v and remaining distance with speed v1 if the average speed of the plane over the journey is 5v/4 then v1​

Answer 1

Explanation:

let Total distance= D

time taken for 1/4th distance= D/4/v =t1

time taken for remaining distance = 3D/4/v1=t2

average speed = D/(t1+t2)=5v/4

5v/4= D/(D/4v+3D/4v1)= 1/(1/4v+3/4v1)

(1/4v+3/4v1)* 5v=4

5/4+15v/(4v1) = 4

5+15v/v1=16

v/v1= 11/15

v1= 15/11v