SOLUTION: The time t required to drive a certain distance varies inversely with the speed r. If it takes 2 hours to drive the distance at 30 miles per hour, how long will it take to drive th

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Question 1090051: The time t required to drive a certain distance varies inversely with the speed r. If it takes 2 hours to drive the distance at 30 miles per hour, how long will it take to drive the same distance at 50 miles per hour?
Found 2 solutions by addingup, Edwin McCravy:
Answer by addingup(3677) About Me  (Show Source):
You can put this solution on YOUR website!
2 hours at 30mph = 60 miles
60/50 = 1.2hours

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
If A varies inversely and B, then the rule is:



[Note for other problems, you might have: In other problems, it'll 
be "directly" instead of "inversely", and in those you'll change
the multiplications above to divisions.]





matrix%281%2C3%2C%0D%0A2%2A30%2C%0D%0A%22%22=%22%22%2C%0D%0AH%2A50%29

matrix%281%2C3%2C%0D%0A60%2C%0D%0A%22%22=%22%22%2C%0D%0A50H%29

matrix%281%2C3%2C%0D%0A60%2F50%2C%0D%0A%22%22=%22%22%2C%0D%0AH%29

matrix%281%2C3%2C%0D%0A6%2F5%2C%0D%0A%22%22=%22%22%2C%0D%0AH%29

6%2F5 of an hour is 1%261%2F5 hours or 1 hour and 12 minutes.

Edwin