Question 286016: Some friends on a hike leave at 9am and return at 2pm. They spend one-quarter of the total distance walking uphill, one-half walking on level ground, and one-quarter walking downhill. if their speed is 4mph on level ground, 2 mph uphill, and 6 mph downhill,approximately how far did they walk?
A. 16.9 miles B. 17.2 miles C. 10.6 miles D. 15.3 E. None of these.
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Some friends on a hike leave at 9am and return at 2pm.
They spend one-quarter of the total distance walking uphill, one-half walking
on level ground, and one-quarter walking downhill. if their speed is 4mph on
level ground, 2 mph uphill, and 6 mph downhill,approximately how far did they walk?
:
"Some friends on a hike leave at 9am and return at 2pm."; therefore
Total time of the walk = 5 hrs
:
let d = total distance
:
"They spend one-quarter of the total distance walking uphill,"
.25d = walking uphill
:
"one-half walking on level ground,"
.5d = walking level ground
:
"and one-quarter walking downhill."
.25d = walking up-hill
:
if their speed is 4mph on level ground, 2 mph uphill, and 6 mph downhill,approximately how far did they walk?
:
Write a time equation; Time = dist/speed
 +  +  = 5
multiply by 12, results:
3(.5d) + 6(.25d) + 2(.25d) = 12(5)
;
1.5d + 1.5d + .5d = 60
:
3.5d = 60
d = 
d ~ 17.2 miles
:
:
Check solution by finding the total time:
 +  +  =
 +  +  =
2.15 + 2.15 + .717 = 5.02 ~ 5 hrs
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