Chapter 22: Mean, Median & Mode

Chapter 22: Mean, Median & Mode

1. Median

   • The middle value in a series of data
     • You will want to organize the data into numerical order from least to greatest
       • When it comes to an even number of numbers in a set of data you will take the two middle values and add them together and then divide them by two to find the median of the two values
   • 65, 72, 51, 32, 39, 63, 59
     • 32, 39, 51, 59, 63, 65, 72
       • This is a series of data with an odd number of values so the middle value is the median
         • The median is 59
   • 65, 72, 51, 32, 39, 63
     • 32, 39, 51, 63, 65, 72
       • This is a series of data with an even number of values so you will take the two middle values and add them and divide by two
       • 51 + 63 = 114 / 2 = 57
         • The median is 57

2. Mean

   • Sum of all values/number of all values
     • 6, 5, 7, 2, 1, 0
       • sum = 21 ; N = 6
         • 21 / 6 = 3.5
           • 3.5 is the Mean
   • Weighted mean
     • Sum of products/sum of frequencies
       • 400, 100, 200, 200, 300, 400, 100
         • values added together = 1700
         • sum of frequencies = 7
           • 1700/7= 242.86
             • 242.86 is the weighted mean

3. Mode

   • The number of values in a series of data that occurs the most
     • 3, 5, 3, 2, 5, 4, 3, 1, 5, 3
       • 3 occurs four times, this one occurs the most so 3 is the mode
       • 4 occurs 1 time
       • 5 occurs three times
       • 1 occurs one time
       • 2 occurs one time