SOLUTION: Chris and Gilbert drove a total of 459 miles in 11.8 hours. Chris drove the first part of the trip and averaged 35 miles per hour. Gilbert drove the remainder of the trip and avera

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Question 906065: Chris and Gilbert drove a total of 459 miles in 11.8 hours. Chris drove the first part of the trip and averaged 35 miles per hour. Gilbert drove the remainder of the trip and averaged 55 miles per hour. For what length of the time did Chris drive?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=11.8,
35*x+55*y=459
x=11.8-y
35*(11.8-y)+55*y=459
413.0-35y+55*y=459
20*y=46.0
y=2.3
x=11.8-y
x=9.5 hr at 35 mph and y=2.3 hr at 55 mph
check
9.5+2.3=11.8
35*x+55*y=459
35*9.5+55*2.3=459
332.5+126.5=459
459.0=459
ok