SOLUTION: An old car has to travel a 2-mile route, uphill and down. Because it is so old, the car can climb the first mile-the ascent-no faster than an average speed of 15 mi/h. How fast doe
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Question 249425: An old car has to travel a 2-mile route, uphill and down. Because it is so old, the car can climb the first mile-the ascent-no faster than an average speed of 15 mi/h. How fast does the car have to travel the second-on the descent it can go faster, or course-in order to achieve an average speed of 30 mi/h for the trip? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! An old car has to travel a 2-mile route, uphill and down.
Because it is so old, the car can climb the first mile-the ascent-no faster than an average speed of 15 mi/h.
How fast does the car have to travel the second-on the descent it can go faster, or course-in order to achieve an average speed of 30 mi/h for the trip?
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This is impossible; the time to go 1 mi at 15 mph, is the same as 2 mi at 30 mph
You have to go the 2nd mile in 0 time, that's fast!
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But let's assume that it is a legitimate problem:
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Let s = the speed down hill
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Time up hill + time down hill = total time + =
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Multiply equation by 30s; results
2s + 30 = 2s
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Obviously this is not possible
