Let's first find the mode of each data set.
Mode = the largest value - the smallest value.
A. 20 - 11 = 9
B. 31 - 5 = 26
C. 20 - 11 = 9
D. 15 - 6 = 9
B fails because its mode does not equal 9.
Let's find the mean of A, C, and D
The mean = the sum of all data values divided by the number of data values.
A. (11 + 11 + 13 + 15 + 20) / 5 = 14.2
C. (11 + 11 + 14 + 19 + 20) / 5 = 15
D. (6 + 10 + 14 + 15 + 15) / 5 = 12
Options A and D fail because their mean does not equal 15.
Let's find the median and mode of option C
Median = the value which falls into the middle of our data set
11, 11, 14, 19, 20 = 14
Mode = the value which appears most often
In option C, 11 appears twice and every other number appears once, therefore, 11 is the mode.
