Sue rides her bike at a rate of 15 mph to May’s house 5 miles away. Then Sue and May walk to

a park 2 miles away at a rate of 3 mph. What was Sue’s average speed for the entire trip?

2 answers

Sue's time riding the bike = 5/15 hrs = 1/3 hr
Sue's time walking the 2 miles = 2/3 hr

total time = 2/3 + 1/3 = 1 hr
total distance = 7 miles
average speed = 7/1 = 7 mph
Sue's time riding the bike = 5/15 hrs = 1/3 hr
Sue's time walking the 2 miles = 2/3 hr

total time = 2/3 + 1/3 = 1 hr
total distance = 7 miles
average speed = 7/1 = 7 mph