Question

How do you find the midpoint in a frequency table?

a) Average the lower and upper class limits.
b) Multiply the lower class limit by the upper class limit.
c) Find the median of the data set.
d) Add the lower and upper class limits and divide by 2.

Answer 1

To find the midpoint in a frequency table, you add the lower and upper class limits of each interval and divide by 2. For instance, the midpoint of the interval 10-20 is calculated as (10+20)/2, equaling 15. This process helps to approximate the mean when dealing with grouped data in a frequency table.

Step-by-step explanation:

To find the midpoint in a frequency table, you should add the lower and upper class limits and divide by 2. For example, if the interval is 10-20, the midpoint would be (10 + 20) / 2, which is 15. This is done for each class interval within the table. Subsequently, if you're calculating an approximation of the mean for grouped data, you might multiply each midpoint by the corresponding class frequency and sum these products. To finalize the approximation, divide this sum by the total number of data values.

Given the options:

• Average the lower and upper class limits.
• Multiply the lower class limit by the upper class limit.
• Find the median of the data set.
• Add the lower and upper class limits and divide by 2..

The correct option for finding the midpoint in a frequency table is (d) Add the lower and upper class limits and divide by 2.