SOLUTION: Going from point A to point B, the cheetah traveled at an average rate of 70 mph. Returning to point A, the cheetah traveled at an average rate of 40 mph. Can we say that this che

Algebra ->  Equations -> SOLUTION: Going from point A to point B, the cheetah traveled at an average rate of 70 mph. Returning to point A, the cheetah traveled at an average rate of 40 mph. Can we say that this che      Log On


   



Question 1036481: Going from point A to point B, the cheetah traveled at an average rate of 70 mph. Returning to point A, the cheetah traveled at an average rate of 40 mph.
Can we say that this cheetah’s average rate was 55 mph?
The average rate for the trip is equal to the total distance traveled divided by the total time traveled. The following equations represent the distance traveled on each leg of the trip.
First leg of trip:
Second leg of trip:
i came up with a distance-rate-time table to help but somewhere along my solution i think i am going wrong.

Answer by ikleyn(52777) About Me  (Show Source):
You can put this solution on YOUR website!
.
Going from point A to point B, the cheetah traveled at an average rate of 70 mph. Returning to point A, the cheetah traveled at an average rate of 40 mph.
Can we say that this cheetah’s average rate was 55 mph?
The average rate for the trip is equal to the total distance traveled divided by the total time traveled. The following equations represent the distance traveled on each leg of the trip.
First leg of trip:
Second leg of trip:
i came up with a distance-rate-time table to help but somewhere along my solution i think i am going wrong.
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Let D be the distance from A to B.

The trip from A to B took t%5B1%5D = D%2F70 hours.

The returning trip from B to A took t%5B2%5D = D%2F40 hours.

The total time for the round trip is 

t%5B1%5D + t%5B2%5D = D%2F70 + D%2F40.

The total distance for the round trip is D + D = 2D.

The average speed for the round trip is 

the_full_distance%2Ffull_time = %282D%29%2F%28t%5B1%5D%2Bt%5B2%5D%29 = %282D%29%2F%28D%2F70+%2B+D%2F40%29 = 2%2F%281%2F70%2B1%2F40%29 = %282%2A40%2A70%29%2F%2840%2B70%29 = 50.909 mph.