SOLUTION: steve McPoke left home on his bivcycle at 8 am. traveling at 18 km/h. at 10 am, steve's brother set out after him on a motorcycle , folowing the same route. The motorcycle travele

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Question 233451: steve McPoke left home on his bivcycle at 8 am. traveling at 18 km/h. at 10 am, steve's brother set out after him on a motorcycle , folowing the same route. The motorcycle traveled at 54 km/h. How long had steve traveled when his brother overtok him?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let's start with the distance formula:
d+=+r%2At where d = distance traveled, r = rate (speed), and t = time of travel. We can write two such equations, one for Steve (1) and the other for his brother (2):
d%5B1%5D+=+r%5B1%5D%2At%5B1%5D and...
d%5B2%5D+=+r%5B2%5D%2At%5B2%5D
Now when Steve's brother on the motor bike overtakes Steve on his bicycle, each will have traveled the same distance, so:
d%5B1%5D+=+d%5B2%5D and, since Steve's brother set out two hours after Steve did (10 am - 8 am), then Steve's time is two hours more than his brother's time, and, of course, the speeds of both are given, so:
t%5B1%5D+=+t%5B2%5D%2B2 Now we have enough information to complete the two equations:
d+=+18%2A%28t%5B2%5D%2B2%29
d+=+54%2A%28t%5B2%5D%29 Since d+=+d we'll set these two equations equal to each other to get:
18%2A%28t%5B2%5D%2B2%29+=+54%2At%5B2%5D Solve for t%5B2%5D
18%2At%5B2%5D%2B36+=+54%2At%5B2%5D Subtract 18%2At%5B2%5D from both sides.
36+=+36%2At%5B2%5D Divide both sides by 36.
t%5B2%5D+=+1 but we want Steve's time (t%5B1%5D, so...
t%5B1%5D+=+t%5B2%5D%2B2 Substitute t%5B2%5D+=+1
t%5B1%5D+=+1%2B2
highlight%28t%5B1%5D+=+3%29
Steved had traveled for 3 hours when his brother overtook him.