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A blue car is moving forward along a straight line. The distance the blue car travels (in meters) from its starting position \(t\) seconds after it started moving is given by \(s(t) = 5t^2\). Suppose the red car travels at a constant speed and travels a distance of \(1375\) meters on the interval \([7,18]\).
Select each of the true statements from the following:
The constant rate of the red car is \(125\)
The average speed of the blue car on this interval is the same as the constant speed of the red car.
The average speed of the blue car on the interval \([7,18]\) is greater than \(s(7)\).
True. The constant rate of the red car is the distance it traveled over the interval \(t=7\) to \(t=18\) divided by the length of this interval which is \(\frac{1375}{11} = 125\)
True. The blue car also travels a distance of \(1375\) meters over the interval \([7,18]\). Therefore, the average speed of the blue car on this interval is the same as the constant speed of the red car.
False. The average speed of the blue car on the interval \([7,18]\) is \[ \frac{s(18)-s(7)}{18-7} = \frac{1620 - 245}{11}= 125 \] which is less than \(s(7)=\) 245
extype: mchoice exsolution: 110 exname: AverageRateOfChange