SOLUTION: Sheri travelled to her cottage and back home again. Her cottage is 90 km from her home.
She averaged 20km/h faster on the trip there than the return trip. Determine Sheri’s aver
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Question 1160527: Sheri travelled to her cottage and back home again. Her cottage is 90 km from her home.
She averaged 20km/h faster on the trip there than the return trip. Determine Sheri’s average speed on
the trip to the cottage if the total time there and back was 1.85 hours.
this is a rational assignment
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!
Elapsed time,
, for a trip of distance
at an average rate of
distance units per time units is given by
She traveled 90km at the rate requested by the question so the outbound trip took
.
The return trip was made at a rate 20 km/hr slower, hence the return trip time was:
.
Since there weren't any side trips or any other anomalies, the total trip time was the sum of the time for the outbound trip and the time for the return trip, to wit:
hours.
which is to say:
Solve for 
John

My calculator said it, I believe it, that settles it

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