Question 363417
Jim and Joe started on trips from San Francisco and traveled in opposite directions.  Jim traveled 15 kph faster than Joe.  After 4 hours, they were 420 km apart.  How fast was each person traveling?
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joe - speed =x kmph
Jim - speed = x+15 kmph
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they are travelling opposite directions so add the speeds
x+x+15 = 2x+15
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distance = 420 km
time = 4
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t= d/r
420/2x+15=4
420=4(2x+15)
420=8x+60
420-60=10x
360=10x
x= 36 kmph speed of Joe
x+15 = 16+15 = 31 kmph = speed of Jim
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m.ananth@hotmail.ca