Answer:
The average speed of Marshall is 29.7 mph
Step-by-step explanation:
Given;
distance traveled to work, d₁ = 27 miles
distance traveled back home, d₂ = 27 miles
initial time taken, t₁ = 1 hour and 20 minutes
final time taken, t₂ = 29 minutes
Total distance traveled, d = d₁ + d₂ = 27 miles + 27 miles = 54 miles
Total time taken for the journey, t = t₁ + t₂ = 1 hour + ( 20 mins + 29 mins)
t = 1 hour + 49 mins = 1 hour + 0.817 hour = 1.817 hour
The average speed is given by;
v = total distance / total time
v = 54 miles / 1.817 hour
v = 29.7 mph
Therefore, the average speed of Marshall is 29.7 mph
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