Question

A car is traveling on a small highway and is either going 55 miles per hour or 35 miles per hour, depending on the speed limits, until it reaches its destination 200 miles away. Letting x represent the amount of time in hours that the car is going 55 miles per hour, and y being the time in hours that the car is going 35 miles per hour, an equation describing the relationship is:
55x + 35y = 200

If the car spends 2.5 hours going 35 miles per hour on the trip, how long does it spend going 55 miles per hour?

Round your answer to the nearest hundredths decimal place.

Answer 1

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Answer:

  2.05 hours

Step-by-step explanation:

Using the given equation with the given time, we have ...

  55x +35(2.5) = 200

  55x = 112.5 . . . . . . . . subtract 87.5

  x = 2.05 . . . . . . . . . . divide by 55

The car spends 2.05 hours at 55 mph.