# S1 - Basic/Quick Question HelpWatch

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#1
Pretend i have some data here e.g 200, 23, 123, 123, 123, 215, 155, 158

Let the mean be X
Let the s.d be Y

if i add another piece of data in there which is = to X

i know the mean will not change but will the standard deviation change?
[simple questions i never have been taught]
0
13 years ago
#2
It would cus ∑(xÂ²)/n would be different.
0
13 years ago
#3
(Original post by nas7232)
Pretend i have some data here e.g 200, 23, 123, 123, 123, 215, 155, 158

Let the mean be X
Let the s.d be Y

if i add another piece of data in there which is = to X

i know the mean will not change but will the standard deviation change?
[simple questions i never have been taught]
Why don't you try it
0
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