1. Averages and the Range The following slides give information about how to calculate the Mean, Median, Mode and Range. Use this information to help you and your group to complete the poster about Smarties by Friday. If you would like to ask any questions, please click on comment below. You will have time (15 minutes) on Friday to stick any work done at home onto the poster.
2. Finding the mode The mode or modal value in a set of data is the data value that appears the most often. For example, the number of goals scored by the local football team in the last ten games is: The modal score is 2 . Is it possible to have more than one modal value? Is it possible to have no modal value? Yes Yes 2, 1, 2, 0, 0, 2, 3, 1, 2, 1. 2 , 1, 2 , 0, 0, 2 , 3, 1, 2 , 1.
3. The mean The mean is the most commonly used average. To calculate the mean of a set of values we add together the values and divide by the total number of values. For example, the mean of 3, 6, 7, 9 and 9 is = = 6.8 Mean = Sum of values Number of values 3 + 6 + 7 + 9 + 9 5 34 5
4. Finding the median The median is the middle value of a set of numbers arranged in order. Write the values in order: 6, 7, 7, 8, 9, 10, 12. The median is the middle value. For example, find the median of 10, 7, 9, 12, 7, 8, 6,
5. Finding the range What does it mean if the range is large? What does it mean if the range is small? The range of a set of data is a measure of how the data is spread across the distribution. To find the range we subtract the lowest value in the set from the highest value. When the range is large it tells us that the values vary widely in size. When the range is small it tells us that the values are similar in size. Range = highest value – lowest value