Question 1046964
Distance=speed * time
Going there, distance= 5.4hrs * x miles per hour
Coming back, distance= 6 hours * (x-4) miles per hour
The distance is the same both ways so set them equal to each other
5.4x=6(x-4)
5.4x=6x-24
-0.6x=-24
x=24/0.6 (minus signs divide out)
=40 mph going
and 36 mph back.
In 5.4 hours at 40 mph it is 216 miles
in 6 hours at 36 mph, it is 216 miles
The answer is the average speed on Thursday, the 6 hour trip.  Her average speed was 36 mph.