Question 644388: Denise and Joan are 28.5 miles apart. at exactly the same time, the begin traveling towards each other. Denise speed is 5 mph less than twice joan's speed. they meet in 90 minutes. How fast does each travel?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Denise and Joan are 28.5 miles apart.
at exactly the same time, the begin traveling towards each other.
Denise speed is 5 mph less than twice joan's speed.
they meet in 90 minutes. How fast does each travel?
:
Since we will be dealing mph, change 90 min to 1.5 hrs
:
s = Joan's speed
then it says "Denise speed is 5 mph less than twice Joan's speed", therefore
(2s-5) = Denise's speed
:
Write a distance equation, dist = time * speed
:
J's dist + D's dist = 28.5 mi
1.5s + 1.5(2s-5) = 28.5
1.5s + 3s - 7.5 = 28.5
4.5s = 28.5 + 7.5
4.5s = 36
s = 36/4.5
s = 8 mph is J's speed
then
2(8)-5 = 11 mph is D's speed
:
:
Check this out by finding distance each traveled.
1.5(8) = 12
1.5(11) = 16.5
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total dist: 18.5
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