SOLUTION: Jim leaves 25 miles from work. He rides his bike at 9mph to the metro which travels at 30mph. He spends 2 minutes less on his bike than on the metro. What's the distance from hi

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Question 676270: Jim leaves 25 miles from work. He rides his bike at 9mph to the metro which travels at 30mph. He spends 2 minutes less on his bike than on the metro. What's the distance from his house to the metro?
The answer is five miles. However, here is how I set it up. 9(x-2) + 30x = 25 and then I tried 9(x-.03) + 30x = 25. Not once did I get the answer. I'm stuck.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Jim leaves 25 miles from work.
He rides his bike at 9mph to the metro which travels at 30mph.
He spends 2 minutes less on his bike than on the metro.
What's the distance from his house to the metro?
:
I don't get that answer either, but because we are using mph, you have to convert two minutes to hrs.
:
let = time to bike to the metro at 9 mph
Change two min to hrs: 2/60 = 1/30 hr
then
(t+1%2F30) = time on the metro at 30 mph
:
WRite a diat equation; dist = speed * time
:
bike dist + metro dist = 25 mi
9t + 30(t+1%2F30) = 25
9t + 30t + 1 = 25; (30's cancel)
39t = 25 - 1
39t = 24
t = 24/39 = 8/13 hrs on the bike
Find the dist
9*8%2F13 = 5.54 miles to the metro
:
:
Check this by finding the distance on the metro
[8%2F13+1%2F30] * 30 =
.6487 * 30 = 19.46 mi on the bus
:
Find the total distances of bike and bus
5.54 + 19.46 = 25 mi, confirms our solution of 5.54 to the metro