SOLUTION: Gravies average driving speed is 4 kilometers per hour faster than Richards. In the same length of time it takes Gracie to drive 265 kilometers Richard drives 252 kilometers. What

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Question 311137: Gravies average driving speed is 4 kilometers per hour faster than Richards. In the same length of time it takes Gracie to drive 265 kilometers Richard drives 252 kilometers. What is gravies average speed?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Gravies average driving speed is 4 kilometers per hour faster than Richards.
In the same length of time it takes Gracie to drive 265 kilometers Richard drives 252 kilometers.
What is gravies average speed?
:
Let s = g's speed
then
(s-4) = r's speed
:
Write a time equation; time = dist/speed
265%2Fs = 252%2F%28%28s-4%29%29
cross multiply
265(s-4) = 252s
265s - 1060 = 252s
265s - 252s = 1060
13s = 1060
s = 1060%2F13
s = 81.538 km/hr is g's speed
:
;
Check the times, they should be equal: (77.538) = r's speed
265/81.538 = 3.25 hrs
252/77.538 = 3.25 hrs