Question 463048: bill begins a 17 mi snowboarding course at 40 mph. 3/5, by time, through the course, he blows out his knee and can only snowboard at 25 mph for the rest of the time . how long in minutes does it take bill to finish the course, start to finish?
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! bill begins a 17 mi snowboarding course at 40 mph. 3/5, by time, through the course, he blows out his knee and can only snowboard at 25 mph for the rest of the time . how long in minutes does it take bill to finish the course, start to finish.
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x=minutes Bill takes to finish the course (total travel time)
distance=travel time * speed
at 40 mph, his travel time=(3/5)x=3x/5
at 25 mph, his travel time=(2/5)x=2x/5
3x/5*40+2x/5*25=17
24x+10x=17
34x=17
x=17/34=1/2 hour=30 min
ans:
Bill takes 30 minutes to finish the course
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