Question

A simple random sample of voters is taken from the voters in a large state. Using the methods of our course, researchers construct an approximate 99% confidence interval for the percent of the state’s voters who will vote for Candidate A. The interval goes from 37.3% to 48.7%.

In the sample, the percent of voters who will vote for Candidate A

is equal to ____________%.

Answer 1

wait

Answer 2

Percent = desired outcome divided by total possibilities.
In the case of a test score: Grade (or percent) = correct answers divided by total questions.

Answer 3

i have 99% -> +-2.575

Answer 4

Sorry, I thought this was going to be a pre-algebra question. Maybe @agent0smith can help when he comes online.

Answer 5

is ok.. thanks..

Answer 6

@Nurali

Answer 7

someone

Answer 8

@texaschic101 @music101 Can you help or do you know someone who can?

Answer 9

no.. but thank you for you help

Answer 10

I am not sure...sorry

Answer 11

what are the methods in your course ?

Answer 12

an example

Answer 13

@phi ...can you help

Answer 14

if anybody knows, he does

Answer 15

I think they want the mid point in the confidence interval

Answer 16

mid point - + 2.575 * (SD/sqr(the voters in a large state)) =S

Answer 17

SD = standard deviation

Answer 18

no, the question asks
the percent of voters who will vote for Candidate A

so the answer is a per cent.

they give you a confidence range which is centered around the per cent who will vote for A

Answer 19

so they want the center of the confidence range. the middle number of the range 37.3% to 48.7%.

Answer 20

mm ( 37.3 +48.7 )/2 ?

Answer 21

yes

Answer 22

ohhh jajaj thanks

Answer 23

the idea is they took a poll, and got 43% as how many are voting for A.
they then figured out the confidence range... you just used the confidence range to figure out what the poll came up with.

Answer 24

mm okok

Answer 25

for example other question . An approximate 95% confidence interval for the percent of the state’s voters who will vote for Candidate A goes from _________% to _________%.

Answer 26

43 - + 1.96 * (SD/sqr(the voters in a large state)) ? .. or ...

Answer 27

you need to find the standard deviation from the info given
then do 43 ± x * std dev
where x is the multiple used for 95% confidence

Answer 28

yes, but SD/stuff is the same thing they used for the 99% confidence interval
figure out what they used, and use it for your question

Answer 29

wait.. If the population size is not given, you can assume that the correction factor for standard errors is close enough to 1 that it does not need to be computed... =S so is SD =1 ?

Answer 30

researchers construct an approximate 99% confidence

they used SD (adjusted for the population). whatever they used, you use

Answer 31

so 43 - + 1.96 * (1/ SQR (n = (.43)(.57)*(1.96/E ))?

Answer 32

SD is 5.7 ?

Answer 33

43-37.3 = error

Answer 34

so 43 - + 1.96 * (1 / SQR ((0,43) (0,57) * (1.96 /5.7 ))

Answer 35

is correct ?

Answer 36

hello ?

Answer 37

I told you phi was good :)

Answer 38

=D thanks so much.. jejje..

Answer 39

xˉ±zα/2×SE ok ... so 43+- 1.96 (SE) SE = ?