10. It is what you get when you add the two numbers together and divide by two and it is the number that is halfway between the two numbers.
The average or mean of 3, 5, 7, 9, and 11 is 7.
The arithmetic mean of 10, 11, and 6 is 9. Add them together then divide by 3.
The answer depends on what you mean by 11 in(n) a half - which is not an expression that is recognised.
5 +9 = 9 + 5 is an example of arithmetic commutativity
The mean average is (7 plus 11) divided by 2 = 9
Median of the set = arithmetic mean of 8 and 9 = 8.5
-9
9 + 22 + 11 = 42
(-9) + (-11-4) + (-11-63) =-9 - 11 - 4 - 11 - 63 = -98
10+11+9+3= 33
11 + 7 + 9 = 27
To find the mean you add them all up then divide by the number of numbers so: 1+3+5+7+9+11 divided by 6 = 36/6 = 6