Can someone explain why this answer is right? Dilpreet drives a distance of 120 miles in 2 hours. She stops for 1 hour to eat lunch and rest. Then she drives another 150 miles in 3 hours. ANSWER: 54 (why is it not 55?)
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Step-by-step explanation:
Average speed = distance / time
Total distance traveled = 120 mi + 150 mi = 270 mi
Total time = 2 hr + 1 hr + 3 hr = 6 hr
Speed = 270 mi / 6 hr = 45 mph
If we ignore the time she was stopped, then her average moving speed is:
Speed = 270 mi / 5 hr = 54 mph