Question

Consider the following data set:

5, 33, 25, 55, 96, 75, 23, 69, 37, 17, 12.

A random sample of size 4 is drawn from the data set. It yields the following numbers: 5, 33, 17, and 23.

What is the population proportion greater than the number 20?

Answer 1

hmm, im thinking that we can run an adjusted z calculation if need be:

find the mean of the sample, and the standard deviation of the population, then we can calculate:\[\Large z=\frac{20-\bar x}{\frac{\sigma}{\sqrt n}}\]

Answer 2

if a recall correctly, we can run a t score if we use the samples standard deviation

Answer 3

ill find the mean and everything in a little, ill comment on this when i back, i have break for summer school right now

Answer 4

k, ill work thru this a little to see if my idea holds any water

Answer 5

i got the mean as 40.6

Answer 6

by hand, i got a mean of the set as 19.5, the standard deviation of the set is sqrt(439/3)

(20-19.5)/sqrt(439/3^2) is approx .... .07159 for a t score of the sample

Answer 7

when i plug that into a tcdf function i get about 47.2

Answer 8

if memory serves, i believe that since the sample size is so small that the t score is opted for ....

Answer 9

alright im back

Answer 10

are you sure thats the mean i got 40.6 and thats one of the answers

Answer 11

the question is not asking you to find the mean of the population

Answer 12

what are all your options?

Answer 13

A.
33




B.
40.6




C.
29.2




D.
50




E.
72.7

Answer 14

if i table a zscore run:\[z=\frac{20-19.2}{27.851/\sqrt 4}=.0359\]which is about 48.6

if we table a tscore run:\[t=\frac{20-19.5}{11.705/\sqrt{4}}=.0854\]
with a degree of freedom of 3, gives me about 46.65

Answer 15

what are you allowed to use for calculating?

Answer 16

what do you mean?

Answer 17

do you have to run it thru with pencil and paper and tabels, or is there a stat program or ti83 that you are able to use?

Answer 18

i dont have to show any work and all i have is a computer

Answer 19

and my phone

Answer 20

have you by chance covered any nonparametric bootstrapping methods in your course?

Answer 21

not that i know of, if you dont know the answer its fine

Answer 22

what about

Answer 23

What is the standard error of the proportion if 80% of the 1,200 respondents in a yes/no survey answered "no"?

Answer 24

standard error is what we did lat time :)

p = .8 q = .2 n = 1200

SE = sqrt(.8*.2/1200)

Answer 25

lol i didnt even notice, thank you so much

Answer 26

:) im still trying to recall how confident i can be with that first stuff tho

Answer 27

your gunnna be the reason i pass algebra 2, and honestly ive been guessing for like 5 straight times

Answer 28

guessing has its merits :)

Answer 29

i found some extra guidance for the first one .. the sample data seems to be irrelevant

Answer 30

can you check out my next question. im stuck

Answer 31

http://answers.yahoo.com/question/index?qid=20130112160359AAGKdp3

Answer 32

thank you (: