SOLUTION: Can someone please help me with this problem: A bike race is completed at an average speed of 15 kph. If the biker had averaged 25 kph, they would have finished the race 1 hour

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Question 533301: Can someone please help me with this problem:
A bike race is completed at an average speed of 15 kph. If the biker had averaged 25 kph, they would have finished the race 1 hour faster. What was the distance that the race covered?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A bike race is completed at an average speed of 15 kph.
If the biker had averaged 25 kph, they would have finished the race 1 hour faster.
What was the distance that the race covered?
:
Let d = distance of the race
:
Write a time equation, time = dist/speed
:
15kmh time - 25kmh time = 1 hr
d%2F15 - d%2F25 = 1
Multiply by 75 to clear the denominators, results
5d - 3d = 75
2d = 75
d = 75%2F2
d = 37.5 km
:
:
Check this by finding the time of each
37.5/15 = 2.5 hrs
37.5/25 = 1.5 hrs
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Time diff: 1 hr