 The range You've probably come across the three different measures of average, mean, median and mode. The range also often gets added onto these three, although it isn't actually a measure of the average, it's the difference between the largest and the smallest value in the data, so the range here is 12 subtract 4, which is 8. The range provides context for the mean, median and mode. If the range is large, then the mean, median or mode might not represent the data very well. Whereas, if the range is small, then they will represent the data well. Given these running times, whose mean, median and mode represents their data more accurately? Pause the video and work out the range. Did you get 8 minutes for Bob and 15 for his friend? Bob's friend has a lot more variation in his data, whereas Bob is much more consistent with his times. You should know how to calculate the mean by adding up all the values and dividing by the number of values and the median by lining them up from smallest to largest and finding the middle one. The mode is the most common value, and then the range by subtracting the smallest value from the largest value. We're going to end this video by working out all four of these for some life expectancies. Pause the video and work them out. Did you get them right? So comparing the means and medians, you can expect to live about two and a half years longer if you don't smoke. To discover the pros and cons of the different measures of average, watch this video. Please like and share our videos with your friends. If you have any questions that you want help with, just comment below.