Question

DF x^2 Calc Command P-value
4 5 x2cdf(
4 10 x2cdf(
4 15 x2cdf(
4 20 x2cdf(
3 15 x2cdf(
4 15 x2cdf(
5 15 x2cdf(
6 15 x2cdf(

Answer 1

Find the p-value for each by filling in the table (don't forget to complete the calculator command):

Answer 2

@reemii @mathstudent55 @Mertsj

Answer 3

No clue

Answer 4

who does?

Answer 5

@electrokid ?

Answer 6

no comprehendo the question

Answer 7

Does this mean (first line) that there is Chi-squared random variable with 4 degrees of freedom that has taken a value equal to 5 and you are asked to give the p-value ?

Answer 8

Do you have the table of the chi-squared?

Answer 9

oh but you have a calculator?

Answer 10

http://sites.stat.psu.edu/~mga/401/tables/Chi-square-table.pdf

Answer 11

find a calculator or use the table given by electrokid.

Look at the curve of the density of the chi-squared(DF=whatever) . Fix some value A. The p-value is the area on the right of A, and it is = P(this chi-square variable > A).

Answer 12

so can you complete it now?

Answer 13

@jim_thompson5910

Answer 14

not exactly sure what they want, but it sounds like they want to know the p value for the given chi-square test statistic (for each row)

Answer 15

Yea they do

Answer 16

they do want that lol @jim_thompson5910

Answer 17

here's a calculator that might be helpful

http://www.fourmilab.ch/rpkp/experiments/analysis/chiCalc.html

Answer 18

you will be using the bottom portion of the page

Answer 19

@jim_thompson5910 i think i got it

Answer 20

is this right? 1. 0.2872
2. 0.0404
3. 0.0047
4. 0.0004
5. 0.0018
6. 0.0047
7. 0.0103
8. 0.0202

Answer 21

let me check

Answer 22

kk

Answer 23

oh sry i misread, it should be the section that's right before the last section

Answer 24

yea thats what i used

Answer 25

oh nvm, you caught it before I did lol

Answer 26

ok let me check

Answer 27

ok

Answer 28

looks great to me

Answer 29

I'm getting the same

Answer 30

cool!

Answer 31

ok i have another one:

Answer 32

Sarah is running a chi-squared Goodness of Fit test to test whether the claimed proportions of candy colors in assorted bags of candy are different than claimed by the company. She takes a random sample of 300 pieces of candy from assorted bags. The company claims the following proportions of colors in assorted bags:

Answer 33

@jim_thompson5910

Answer 34

looking up formula

Answer 35

ok

Answer 36

did u find it @jim_thompson5910 lol

Answer 37

well that's the thing, I think i have an idea on how to do this...but it seems like something is missing

Answer 38

not 100% sure though

Answer 39

ok what do u think?

Answer 40

@jim_thompson5910

Answer 41

@jim_thompson5910 ?

Answer 42

ok i see the proportions given by the company, but what are the actual sample counts?

Answer 43

where do i find that?

Answer 44

it doesn't give it out?

Answer 45

no the full problem is up there ^

Answer 46

hmm ok

Answer 47

soo

Answer 48

i'm not entirely sure, the company gives out the claimed data, but there's no sample data to work with

Answer 49

see what I mean?

Answer 50

ya thats true it says

Answer 51

wait did u see the screenshot?

Answer 52

@jim_thompson5910

Answer 53

yeah i saw that, that's the company's claimed data

Answer 54

but there's nothing to compare it to

Answer 55

ummm

Answer 56

Heres question again: Sarah is running a chi-squared Goodness of Fit test to test whether the claimed proportions of candy colors in assorted bags of candy are different than claimed by the company. She takes a random sample of 300 pieces of candy from assorted bags. The company claims the following proportions of colors in assorted bags:

Answer 57

Then its the pic. and it says What are the expected results of each color?

Answer 58

does it give you any info on what kind of sample she got?

Answer 59

Nope thats all of it.

Answer 60

it says she takes a random sample

Answer 61

lame, there's definitely missing info in my opinion

Answer 62

but I'm not 100% sure if that's the case or not

Answer 63

so wat do i do

Answer 64

could it be a typo maybe that this info is missing?

Answer 65

If i were in your shoes, I would ask the teacher about it and maybe the info will be given then?

Answer 66

oooh wait...we just want the expected results

we don't need the sample

Answer 67

not thinking at all

Answer 68

but you just multiply the values in the table with the total 300

Answer 69

lol ok

Answer 70

how?

Answer 71

example:

0.2 is in the green column

so you expect there to be 0.2*300 = 60 green

Answer 72

do the same for the rest

Answer 73

unfortunately we can't go any further with the goodness of fit test because we will still need the observed results (ie the stuff in the sample), but that's ok

Answer 74

Green: .2 times 300 = 60
Yellow: .3 times 300 = 90
Red: .3 times 300 = 90
Blue: .2 times 300 = 60

Answer 75

is this right?

Answer 76

yep

Answer 77

ok thats the answer? ok thx one more

Answer 78

A regular 6-sided die is tossed 200 times with the faces turning up as follows:

Answer 79

if you toss a die 200 times, how many times do you expect to get a 1 on the die

Answer 80

ummm

Answer 81

idk?

Answer 82

what are the chances of rolling a 1 on a six sided die

Answer 83

1/6

Answer 84

multiply that with 200

Answer 85

200/6?....

Answer 86

write in decimal form though

Answer 87

33.3333333333

Answer 88

so roughly 33

Answer 89

if you round to the nearest integer

Answer 90

this means that you expect to get a '1' on the die 33 times

Answer 91

if you roll it 200 times total

Answer 92

okay