Let's go down the list:
A: The median is the middle number when the sets of data are in numerical order. The mean is the average, also known as taking all the numbers, adding them up, then dividing by the amount of numbers you added up. If the median=mean, this means that the middle number is the same as the average. Let's take a look
Sierra's numbers: 2, 11, 12, 13, 15 ← Since these numbers are already in order, the middle number is 12. Let's find the average, now. So we want to add up all those numbers: (2+11+12+13+15) = 53. Since we added up 5 numbers, we want to divde by 5. 53/5=10.6 ≠ 12. Therefore, this statement is not true.
B. Have a more "spread out" data means that the range of numbers is greater. Therefore, let's see. Seirra's numbers go from 2 to 15, while Alek's numbers go from 9 to 13. Seirra has a larger range of numbers. Therefore, this statement is correct.
