Question

finish times (to the nearest hour) for 10 dogsled teams are shown below.
find the class width. use five classes. (round your answer to the nearest integer.)
252, 314, 315, 284, 255, 245, 292, 335, 244, 342
options: 21, 119, 117, 20, 22

Explanation:

Step1: Find min and max

First, identify the minimum and maximum values in the data set. The data points are 252, 314, 315, 284, 255, 245, 292, 335, 244, 342. The minimum value ($\text{min}$) is 244, and the maximum value ($\text{max}$) is 342.

Step2: Calculate range

The range is calculated as $\text{max} - \text{min}$. So, $342 - 244 = 98$.

Step3: Determine class width

We need to use 5 classes. The class width is calculated by dividing the range by the number of classes and rounding up to the nearest integer. So, $\frac{98}{5} = 19.6$. Rounding up to the nearest integer gives 20. Wait, but let's check again. Wait, maybe I made a mistake. Wait, the formula for class width is usually $\lceil \frac{\text{max} - \text{min}}{\text{number of classes}}
ceil$. So $\frac{342 - 244}{5} = \frac{98}{5} = 19.6$, so we round up to 20? But wait, let's check the options. Wait, the options include 20. Wait, but let's re - evaluate. Wait, maybe I miscalculated the min and max. Let's list all the data points: 244, 245, 252, 255, 284, 292, 314, 315, 335, 342. So min is 244, max is 342. Range is 342 - 244 = 98. Number of classes is 5. 98 divided by 5 is 19.6. When we round up to the nearest integer, we get 20. But wait, let's check the options. The options are 21, 119, 117, 20, 22. So the correct class width is 20? Wait, no, wait. Wait, maybe the formula is $\frac{\text{max}-\text{min}}{\text{number of classes}}$ and then round to the nearest integer. 98/5 = 19.6, which is approximately 20 when rounded to the nearest integer. So the class width is 20.

Answer:

20