Krishna
0

Step 1: Recall the mean definition and look at the given information.

             NOTE: The mean (or arithmetic mean) of n observations (variates)

                          n is given by x_1, x_2, x_3, x_4..................x_n

                            Mean = \frac{\text{ Sum of the variables}}{\text{Total number of variables}}

                                       = \frac{x_1+x_2+x_3+x_4.............x_n}{n}

              (Mean: The mean is the average of the numbers. You find the mean by

              adding the numbers together and then dividing by the number of numbers

               in the group.)


Step 2: Count how many numbers are in the group.

                12, 10, 15, 10, 16, 12, 10, 15, 15, 13

                There are 10 numbers


Step 3:  Add all the numbers together

              12 + 10 + 15 + 10 + 16 + 12 + 10 + 15 + 15 + 13 = 128

                

Step 4: Now divide the sum by the number of numbers

               Mean = \frac{128}{10}


               The mean = 12.8