Oliver and Lenny started hiking a hill simultaneously from the bottom to the top. Oliver hiked at a speed of 5 km/h during the first half, then decreased his speed to 4 km/h during the second half. Lenny hiked at a speed of 4 km/h during the first half, then increased his speed to 5 km/h in the second half. Who reached the top of the hill first? What is the proportion of time he spent hiking to that of his friend? THE PROPORTION IS NOT 1:1, ALSO, LENNY REACHED FIRST
