Question

Use the table to answer the question.

This table displays the relationship between hours traveled and miles covered.
Time (hours) 0 4 7 9 12
Distance (miles) 0 248 449 565 757
The Diaz family went on a road trip for vacation. The table includes a cumulative chart of the time they traveled compared to the distance they drove. Over which interval was their average speed the fastest: [0,4]
, [4,7]
, [7,9]
, or [9,12]
? Explain your reasoning in 1–2 sentences.

Answer 1

Compute average speeds: [0,4] = 248/4 = 62 mph; [4,7] = 201/3 = 67 mph; [7,9] = 116/2 = 58 mph; [9,12] = 192/3 = 64 mph. The fastest interval is [4,7] since 67 mph is the largest average speed.