Question

What is the standard deviation of the data set?

6 4 9 5 5 4 5






≈5.4



≈1.6



≈5.0



≈1.7

Answer 1

i did the variance and got 2.530612244898 but what do i do now??

Answer 2

When stuck with something like this, please look up the concept involved. Here, I looked up "standard deviation" and came up with

http://www.mathsisfun.com/data/standard-deviation.html

Please look at the formulas for standard deviation listed under "Formulas."

Answer 3

I imagine you got the variance using your calculator.

The std. dev. is the sqrt of the variance.

Round off your result. I'd suggest no more than 2 decimal places.

Answer 4

2.53

Answer 5

That is the variance of the data set. Take the square root of the variance to get the standard deviation.

@ayonnaleflore

Answer 6

i got 1.53 which could be 1.7

Answer 7

I got 1.72 which is really close to 1.7.

This is a good online calculator: http://web2.0calc.com/

Answer 8

Better check: Are you expected to know the formula(s) for variance / std. deviation and to apply them, or expected only to be able to find these using a calculator?

Answer 9

@mathmale i am just simply expected to be able to answer the questions and i still dont know how to do it without a calculator

Answer 10

I've searched the Internet for a good and straightforward explanation of how to calculate variance and standard deviation without a calculator. Please look over the following:

http://www.mathsisfun.com/data/standard-deviation-formulas.html

If you have any problem understanding this, just ask.