Marlene rides her bicycle to her friend Jon's house and returns home by the same route. Marlene ride her bike at constant speeds of 9 mph on level ground, 6 mph going uphill and 18 going downhill. If her total riding time was 2 hrs, how far is it to Jon's house. (below is a picture of a trapezoid)

Question

anonymous · Answer

I think it is averagespeed=distance/time so (9+6+18)=d/2 but you may need to know or use the distance of the trapezoid to figure out how far they road on each stretch. answer comes out to be 66 miles

anonymous · Answer

that can't be right. haha I did this question online the other day where the constant was 9 mph, uphill was 6, and downhill 18 mph. But the total riding time was 1 hr. I got the question wrong but the distance was supposed to be 4.5 miles