Tom went on a car trip. During the first hour, he covered 60 miles. After the second hour, he had covered 102 miles. He had driven a total of 172 miles after 3 hours, and he made it to his destination, 222 miles away, after 4 hours.
Did Tom have a faster average speed over the first hour, the second hour, the third hour, or the fourth hour?
The third hour
The second hour
The fourth hour
The first hour
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Tom went on a car trip covering different distances each hour. We have his cumulative distances: 60 miles after 1 hour, 102 miles after 2 hours, 172 miles after 3 hours, and 222 miles after 4 hours. To find which hour had the fastest average speed, we need to calculate the distance traveled in each individual hour and apply the formula: average speed equals distance divided by time.
Now let's calculate the distance traveled in each individual hour. Since we have cumulative distances, we subtract the previous total from each hour's total. Hour 1: 60 minus 0 equals 60 miles. Hour 2: 102 minus 60 equals 42 miles. Hour 3: 172 minus 102 equals 70 miles. Hour 4: 222 minus 172 equals 50 miles. The bar chart shows these individual hourly distances clearly.
Now we calculate the average speed for each hour using the formula: speed equals distance divided by time. Since each time interval is exactly 1 hour, the calculations are straightforward. Hour 1: 60 miles divided by 1 hour equals 60 miles per hour. Hour 2: 42 divided by 1 equals 42 miles per hour. Hour 3: 70 divided by 1 equals 70 miles per hour. Hour 4: 50 divided by 1 equals 50 miles per hour.
Now let's compare all the calculated speeds to find the answer. Hour 1 had 60 miles per hour, Hour 2 had 42 miles per hour, Hour 3 had 70 miles per hour, and Hour 4 had 50 miles per hour. Looking at our comparison chart, we can clearly see that the third hour has the highest speed at 70 miles per hour. This makes sense because Tom covered the most distance, 70 miles, during the third hour. Therefore, the answer is that Tom had the fastest average speed during the third hour.