13. (9+17)/2=13
13
Average = 13
You average the two numbers in the middle. For example, if you have the numbers 9, 13, 17, and 20, the median is the average of 13 and 17, which is 15.
9, 11, 13, 15, 17, 19, 21
13. (9+17)/2=13
13
Average = 13
1 5 9 13 17 21
5, 13 and 17 are prime.
You average the two numbers in the middle. For example, if you have the numbers 9, 13, 17, and 20, the median is the average of 13 and 17, which is 15.
9, 11, 13, 15, 17, 19, 21
13 + 9 + 17 = 39
Add them together and divide by 6.
Between 9 and 17. 9 being very early and 17 being very late. That makes 13 the average age.
Mean is the same as average
11/21 or 9/17 can be equaled by multiplying the caller. so 11/21 becomes: 17*11 and 17*21= 187/357 and 9/17 becomes: 21*9 and 21*17= 189/357 As can be seen 189/357 > 187/357. So 9/17 > 11/21