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?
: 
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+{{{1/30}}}) = time on the metro at 30 mph
:
WRite a diat equation; dist = speed * time
:
bike dist + metro dist = 25 mi
9t + 30(t+{{{1/30}}}) = 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*{{{8/13}}} = 5.54 miles to the metro
:
:
Check this by finding the distance on the metro
[{{{8/13}}}+{{{1/30}}}] * 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