SOLUTION: Please help me with the following problem. Jim bicycled from his home to school at 8 mph. He returned home at 4 mph. If the round trip took 3 hours, how many miles is it from s

Algebra ->  Length-and-distance -> SOLUTION: Please help me with the following problem. Jim bicycled from his home to school at 8 mph. He returned home at 4 mph. If the round trip took 3 hours, how many miles is it from s      Log On


   



Question 121863: Please help me with the following problem.
Jim bicycled from his home to school at 8 mph. He returned home at 4 mph.
If the round trip took 3 hours, how many miles is it from school to
Jim's home?
Answers:
a) 1 mile
b) 2 miles
c) 4 miles
d) 6 miles
e) 8 miles

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Jim bicycled from his home to school at 8 mph. He returned home at 4 mph.
If the round trip took 3 hours, how many miles is it from school to
Jim's home?
:
let d = distance one way from home to school
:
Write time equation: Time = distance%2Fspeed
:
d%2F8 + d%2F4 = 3
:
Get rid of the denominators, multiply equation by 24 (a multiple of 8 and 6)
24*d%2F8 + 24*d%2F4 = 24(3)
Cancel out the denominators and you have:
:
3d + 6d = 72
9d = 72
d =72%2F9
d = 8 mi
:
:
Check solution by finding the times
8/8 + 8/4 = 3