Measures of Center

Front

What is the mean?

Back

The mean is the average of a set of numbers, calculated by adding all the numbers together and dividing by the total count of numbers.

Front

How do you find the mean of the following numbers: 90, 100, 95, 85, 60, 80?

Back

Add the numbers: 90 + 100 + 95 + 85 + 60 + 80 = 510. Then divide by the count of numbers (6): 510 / 6 = 85.

Front

What is the median?

Back

The median is the middle number in a sorted list of numbers. If there is an even number of observations, the median is the average of the two middle numbers.

Front

How do you find the median of the following numbers: 77, 99, 80, 78.5?

Back

First, sort the numbers: 77, 78.5, 80, 99. Since there are 4 numbers (even), the median is the average of the two middle numbers: (78.5 + 80) / 2 = 79.25.

Front

What is the mode?

Back

The mode is the number that appears most frequently in a data set.

Front

If the data set is 1, 2, 2, 3, 4, what is the mode?

Back

The mode is 2, as it appears most frequently.

Front

What is the range of a data set?

Back

The range is the difference between the highest and lowest values in a data set.

Front

Find the range of the following numbers: 10, 15, 20, 5.

Back

Range = Highest value - Lowest value = 20 - 5 = 15.

Front

What is a dot plot?

Back

A dot plot is a simple way to display data using dots above a number line, where each dot represents one occurrence of a value.

Front

How do you find the median from a dot plot?

Back

Count the total number of dots. If odd, the median is the middle dot. If even, the median is the average of the two middle dots.