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3 years ago

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If a car travels 30.0 mi. north for 30.0 min., 50.0 mi. east for 1.00 hour, and 30.0 mi. south for 30.0 min., what is the averag

e speed of the car over the total trip? 55 mph 55.0 mph 60.0 mph 60. mph

1 answer:

san4es73 [151]3 years ago

4 0

Note that Speed = Distance/Time.

1st trip:
Distance = 30 mi
Time = 30 min = 0.5 h
Speed = 30/0.5 = 60 mi/h

2nd trip:
Distance = 50 mi
Time = 1 hour
Speed = 50 mi/h

3rd trip:
Distance = 30 mi
Time = 30 min = 0.5 h
Speed = 30/0.5 = 60 mi/h

Average speed = (60 + 50 + 60)/3 = 56.7 mph
The closestanswer is 55 mph

Answer: 55 mph

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Using eqn (2) in (1):

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