+546 6)Find the mean, variance, and standard deviation for each data set. 6. 78 90 456 673 111 381 21
10)The Dow Jones Industrial average for the first 12 weeks of 1988: find the mean and standard deviation!: 1911.31 1956.07 1903.51 1958.22 1910.48 1983.26
2014.59 2023.21 2057.86 2034.98 2087.37 2067.14
12) Th e mean price of the nonfi ction books on a best- sellers list is $ 25.07; the standard deviation is $ 2.62. $ 26.95, $ 22.95, $ 24.00, $ 24.95, $ 29.95, $ 19.95, $ 24.95, $ 24.00, $ 27.95, $ 25.00
14)Find the standard deviation for each data set. Use the standard deviations to compare each pair of data sets. fastest recorded speeds of various large wild cats ( miles per hour): 70 50 30 40 35 30 30 40 15 fastest recorded speeds of various birds in fl ight ( miles per hour): 217 106 95 56 65 37 50 31 53 25 25 25
+118608 ok Nataszaa,
I am not trying to be harsh. Do you have to do them by hand - without using a statistics calculator.
We need to know what the rules are.
Here is a page to help you understand what you have to do.
http://www.mathsisfun.com/data/standard-deviation.html
If you need to do it by hand then you will need to draw up columns. I am too tired to show you that now. It is 3:40am here. but you will need to work out the means first anyway. Work out the means and then if you need more help either I or someone else will definitely help you some more.
Goodnight Natasza. 
+118608 I think that you asked this question a day or 2 ago Nataszaa.
You must be able to do some of it yourself.
Mean is the same as average - add up all the numbers and divide by how many there are.
Are you expected to find these values using your calculator? Do you know how to do this?
Would you like someone to help you? You will need to tell us what model calc you are using.
Try and be specific about what your problems are. We give our time and knowledge freely to you because we want to help you learn. NOT because we want to do your homework for you. 
+546 i dont have a calculator. i have no idea how to do these which is why i am posting them!
+118608 ok Nataszaa,
I am not trying to be harsh. Do you have to do them by hand - without using a statistics calculator.
We need to know what the rules are.
Here is a page to help you understand what you have to do.
http://www.mathsisfun.com/data/standard-deviation.html
If you need to do it by hand then you will need to draw up columns. I am too tired to show you that now. It is 3:40am here. but you will need to work out the means first anyway. Work out the means and then if you need more help either I or someone else will definitely help you some more.
Goodnight Natasza.
+33614 Mean
Add up all the numbers and divide by how many there are.
Variance
First find the difference between each number and the mean. Square each of these differences. Add up all these squared differences. Divide the result by one less than how many there are (i.e. if you have 8 numbers, then divide by 7).
Standard deviation
This is just the square root of the variance.
Calculator
There is one on the home page of this site.
Let's see you have a go at these and then perhaps someone will check your answers.
