Answer: Tim's average speed is greater
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Step-by-step explanation:
Lara traveled a total distance of
AB+BC = (6 miles)+(2 miles) = 8 miles
and did so in
(1.5 hours)+(1 hour) = 2.5 hours
Plug those values into the formula
r = d/t
and we get
r = (8 miles)/(2.5 hours)
r = (8/2.5) mph
r = 3.2 mph
Lara's average speed is 3.2 mph
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We'll follow the same steps for Tim as well
total distance = AE+ED+DC
total distance = (2 mi)+(4 mi)+(6 mi)
total distance = 12 miles
total time = (0.5 hr)+(1.5 hr)+(1.5 hr)
total time = 3.5 hours
rate = distance/time
r = d/t
r = (12 miles)/(3.5 hours)
r = (12/3.5) mph
r = 3.42857 mph approximately
Tim's average speed is roughly 3.42857 mph. We see that he has the greater average speed.