SOLUTION: Katrina drove her car to Boston at a speed of 100 kph (kilometers per hour). She drove back at 75 kph. The total driving time was 7 hours. How far away was Boston?
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Question 256566: Katrina drove her car to Boston at a speed of 100 kph (kilometers per hour). She drove back at 75 kph. The total driving time was 7 hours. How far away was Boston? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Katrina drove her car to Boston at a speed of 100 kph (kilometers per hour).
She drove back at 75 kph. The total driving time was 7 hours.
How far away was Boston?
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Let d = distance to Boston
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Write a time equation: Time = dist/speed
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To B. time + from B. time = 7 hrs + = 7
Multiply by 300 to get rid of the denominator, results
3d + 4d = 300(7)
7d = 2100
d =
d = 300 mi to B.
:
:
Check solution, find the time of each trip
300/100 = 3 hrs
300/75 = 4 hrs
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total = 7 hrs
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That's pretty easy, right?
