Question 830352
x time up
y time down
d one-way distance up or down


________________speed___________time________________distance
up hill_________2________________x__________________d
down hill_______4________________y__________________d
Total?________________________x+y__________________2d



The relationship of speeds means you can make a relationship of the times.

Twice as fast down the hill means HALF the time as up the hill:


________________speed___________time________________distance
up hill_________2________________x__________________d
down hill_______4________________x/2__________________d
Total?________________________(3/2)x__________________2d


Can we find expressions for d?



________________speed___________time________________distance
up hill_________2________________x__________________d=2x
down hill_______4________________x/2__________________d=4(x/2)
Total?________________________(3/2)x__________________2d=4x



SPEED is distance divided by time:
We want total distance and total time.
{{{(4x)/((3/2)x)=4/(3/2)=(4*2)/3=8/3=highlight(2&2/3)}}} mph.
This is a little greater than what value you expected.