First we find the mean (average)
(7 + 8 + 9 + 9 + 10 + 11)/6 = 54/6 = 9
now we subtract the mean from every data number....and square it
7 - 9 = -2...-2^2 = 4
8 - 9 = -1...-1^2 = 1
9 - 9 = 0....0^2 = 0
9 - 9 = 0...0^2 = 0
10 - 9 = 1....1^2 = 1
11 - 9 = 2....2^2 = 4
now we find the mean (average) for those numbers
(4 + 1 + 0 + 0 + 1 + 4) / 6 = 10/6 = 1.67...this is the variance
to find the standard deviation, take the sqrt of the variance
sqrt 1.67 = 1.29 <== ur answer
Are there answer choices? If not, the older brother will get 5, and the younger sister will get 4.
Answer:
105 is corresponding to angle B, meaning they are congruent. B and x are supplementry meaning they should add up to equal 180.
Since 180 - 105 = 75, those would be your steps and x is 75
Step-by-step explanation:
