Question

Use the data to find the class width if we want 6 classes.

12 18 27 31 40 42 14 20 27 32 40 51 14 20 27 32 40 56 14 21 29 34 40 60 16 23 31 36 40 65

Answer 1

To find the class width when we want 6 classes, we first need to find the range of the data, which is the difference between the largest and smallest values:

Range = Largest value - Smallest value

Range = 65 - 12

Range = 53

Next, we need to divide the range by the number of classes we want (6) to find the approximate class width:

Approximate class width = Range / Number of classes

Approximate class width = 53 / 6

Approximate class width ≈ 8.8

We want to choose a class width that is easy to work with, so we can round up the approximate class width to the nearest convenient value, such as 10:

Class width ≈ 10

This means that we can create classes that cover ranges of 10 units in the data, such as 10-19, 20-29, 30-39, and so on.

Answer 2

To find the class width if we want 6 classes, we first need to find the range of the data.

Range = maximum value - minimum value

In this case, the minimum value is 12 and the maximum value is 65, so the range is:

Range = 65 - 12 = 53

Next, we divide the range by the number of classes we want (6) to get an initial estimate of the class width:

Class width = Range / Number of classes

Class width = 53 / 6

Class width ≈ 8.8

However, we want the class width to be a nice, round number, so we can round up to 9.

Therefore, if we want 6 classes, the class width would be 9.