how do i find standard deviation using my graphing calc?

Question

jim_thompson5910 · Answer

what kind of graphing calculator do you have?

anonymous · Answer

ti-83

jim_thompson5910 · Answer

click the stat button

jim_thompson5910 · Answer

go to edit, then enter your values into L1 or any other free list

jim_thompson5910 · Answer

once you've entered the values into L1, click stat again, and go to the "calc" menu

finally, click "1-var stats"

jim_thompson5910 · Answer

then hit enter

anonymous · Answer

okay...i did all of that...which symbol corresponds to the standard deviation?

jim_thompson5910 · Answer

Sx represents the sample standard deviation

$\LARGE \sigma_{x}$ represents the population standard deviation


Since you won't know much about the population in much of stats, I think it's safe to assume they want you to find the sample standard deviation.

anonymous · Answer

awesome thank you!! and does one of those symbols correspond to the variance by chance?

jim_thompson5910 · Answer

variance = (standard deviation)^2

jim_thompson5910 · Answer

and there are two types of variance

sample variance

population variance


They correspond to the sample standard deviation and population standard deviation respectively

jim_thompson5910 · Answer

Most likely you'll be dealing with the sample variance (since again, you won't know much about the population in general), but some problems may provide you with the population variance

anonymous · Answer

okay...well for one of the problems im doing i have the set of data 7,8,4,10,6,10 and found the standard variation to be 2.3..but when i squared it to find the variance..the answer i got doesnt match any of my answer choices

jim_thompson5910 · Answer

what are your answer choices?

anonymous · Answer

a. v=4.6 sd=2.3
b. v=1.5 sd=2.1
c. v=1.5 sd=2.3
d. v=4.6 sd=2.1

jim_thompson5910 · Answer

what was your population standard deviation?

anonymous · Answer

2.14

jim_thompson5910 · Answer

2.3^2 = 5.29 which isn't an answer choice

and

2.1^2 = 4.41 which isn't an answer choice either

So something is off...

jim_thompson5910 · Answer

There has to be a typo in the answer choices

anonymous · Answer

well there might be..but i sure hope not!! this is a online course homework assignment

jim_thompson5910 · Answer

or if you use 2.14 as the sd, then

2.14^2 = 4.5796 which rounds to 4.6

but the 2.3 one is way off

jim_thompson5910 · Answer

so perhaps they want you to use the population standard deviation

jim_thompson5910 · Answer

and it looks like choice D is the answer

anonymous · Answer

ok ill go with that, thanks for your help!

jim_thompson5910 · Answer

you're welcome