Answer:
[tex]\frac{v2+v1}{2}[/tex], where v2= velocity at the end and v1= velocity in the beggining
Explanation:
Asuming that v=K, where k= velocity lower than 60[km/h] we can make an equation for a average speed to entire trip as follows:
The equation of average is: [tex]\frac{v2+v1}{2}[/tex], where v2= velocity at the end and v1= velocity in the beggining. Where v1=60 [km/h] becouse is the average velocity of half trip, and v2=k.
That means that jhon´s average speed decreses