Question 993724
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Your teacher's suggestion for this problem, while not technically incorrect, is certainly an unnecessary trip around Robin Hood's barn.


Average speed is calculated by dividing the total distance traveled by the total time it took to travel that distance.  Your teacher's formula certainly does that.  However, you are given distance and time for each of the legs of the trip, so in order to calculate the rate for each leg you would have to divide the distance by the rate, and then use that rate times the time for each leg to find the distance for each leg.  You would be doing two divisions and two multiplications to find two numbers you already have in the statement of the problem.  Sort of like buying a car, taking it apart, and then reassembling it so that you will have something to drive.


Average rate is simply the sum of the two distances given divided by the sum of the two times given.


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it

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