SOLUTION: newport and vernonville are 112 miles apart. a car leaves newport travelling toward vernonville and another car leaves vernonville at the same time travelling to newport. the car

Algebra ->  Rational-functions -> SOLUTION: newport and vernonville are 112 miles apart. a car leaves newport travelling toward vernonville and another car leaves vernonville at the same time travelling to newport. the car      Log On


   

Question 1039763: newport and vernonville are 112 miles apart.
a car leaves newport travelling toward vernonville and another car leaves vernonville at the same time travelling to newport. the car leaving newport averages 10 miles per hour more than the other and they meet after 1 hour and 36 minutes. what are the average speed of the cars.

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thank you!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
You can think of this as one of the cars standing
still and the other covering the distance between them
traveling at the sum of their speeds
---------------------------------
Let +s+ = the speed of the slower car
+s+%2B+10+ = the speed of the faster car
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convert +36+ min to hrs
+36%2F60+=+.6+
+1+%2B+.6+=+1.6+ hrs
-----------------------
+112+=+%28+s+%2B+s+%2B+10+%29%2A1.6+
+112+=+%28+2s+%2B+10+%29%2A1.6+
+112+=+3.2s+%2B+16+
+96+=+3.2s+
+s+=+30+
and
+s+%2B+10+=+40+
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Car leaving Vernonville ( slower car ) averages 30 mi/hr
Car leaving Newport ( faster car averages 40 mi/hr
-----------------
check answer:
+d%5B1%5D+=+30%2A1.6+
+d%5B1%5D+=+48+ mi
and
+d%5B2%5D+=+40%2A1.6+
+d%5B2%5D+=+64+ mi
-----------------
+d%5B1%5D+%2B+d%5B2%5D+=+48+%2B+64+
+d%5B1%5D+%2B+d%5B2%5D+=+112+
OK