Question

@ganeshie8
http://openstudy.com/users/yanasidlinskiy#/updates/56fe903ee4b0261a951e2266
^^^^^ That's the mean and Standard Deviation calculated..

Answer 1

Both of my Standard Deviation and Mean are wrong. I don't know what I'm doing wrong but...

Answer 2

Both Top and bottom, I got.. .0263 and .9737.. Now my mean and standard deviation were wrong. Any idea?

Answer 3

part a looks good!

Answer 4

Yea, Ik part B tho is what's killing me

Answer 5

mean = 35*(1/38) + (-1)*37/38

right ?

Answer 6

Yes.

Answer 7

and your grader says that is wrong is it ?

Answer 8

Yes.

Answer 9

mean = 35*(1/38) + (-1)*37/38 = -0.0526

I don't really how the mean can be anything different...

Answer 10

Do you think it could be the negative though?

Answer 11

Yea, it just means you lose your money if you play the game too many times

Answer 12

mean could be negative, zero, or positive

Answer 13

It happens to be negative in our case
nothing unusual

Answer 14

It has to be negative
otherwuse how can the casinos survive ?

Answer 15

Okay, here's what my Professor said:
-0.05 is the mean
5.76 is the standard deviation.
No idea how they got it.

Answer 16

what do you mean you don't get it

Answer 17

Like how did they get a wayyyy different answer that me and Hartnn got...?

Answer 18

don't you see your professor has rounded the mean to two decimal places instead of four ?

Answer 19

I know that....<< But like we got 24...***** and she got 5.76...

Answer 20

are you talking about standard deviation now ?

Answer 21

Yes....

Answer 22

good with mean ?

Answer 23

What?

Answer 24

you were complaining about both `mean` and `standard deviation` earlier

Answer 25

Ughgh. The F standard Deviation. How the f did they get a complete different answer than what I had

Answer 26

I am asking if you're okay with mean

Answer 27

Yes,... I am....

Answer 28

Good. Whats the value of mean that you're using ?

Answer 29

What was the mean?

Answer 30

haven't you calculated the mean yet ?

Answer 31

I already posted what I had for the mean...^^^^^^^

Answer 32

you have posted two values
i need to know the specific value that you're going to use to calculate standard deviation

Answer 33

-0.05

or

-0.0526

Answer 34

2nd one.

Answer 35

Okay, plug that in standard deviation formula

Answer 36

http://www.wolframalpha.com/input/?i=sqrt((35%5E2*1%2F38+%2B+(-1)%5E2*37%2F38)+-(-+0.0526)%5E2)

Answer 37

looks your professor is correct, the stadanrd deviation is indeed 5.76

may i see how you managed to get 24 ?

Answer 38

Yes..

Answer 39

http://www.wolframalpha.com/input/?i=%5Csqrt+%7B%5Cdfrac%7B1%7D%7B2%7D+%5B(35-(-0.0526))%5E2%2B(-1-(0.0526))%5E2%5D%7D

Answer 40

you're using wrong formula for standard deviation

Answer 41

Ok. Thank you.

Answer 42

you may use the formula from here...
https://people.richland.edu/james/lecture/m170/ch06-prb.html

Answer 43

Ok