Question

Please help!!
The difference between the sample means of two populations is 34.6, and the standard deviation of the difference between sample means is 11.9. What is the 95% confidence interval?

Answer 1

\[(\bar x-\bar y) \pm z_{95\%}\sqrt{\frac{\sigma_1}{m}+\frac{\sigma_1}{n}}\]

Answer 2

the difference of the means they give you, and the z score of 95% is what .. 1.96 right?

Answer 3

do i just plug 34.6 and 11.9 in the equation?

Answer 4

im so confused right now lol

Answer 5

wow you even memorized the z table? wow

Answer 6

lol, its a short table :)

Answer 7

i wish i was good at stat

Answer 8

don't we all

Answer 9

since there is not sample sizes given, id have to refresh the proper rundown. Im thinking that we could just consider them to be equal sizes of 100 but thats prolly not correct.

Answer 10

E.between -103.8 and +103.8
if you mean answers thats the only one even close to 100

Answer 11

the rest are 69 and below

Answer 12

difference of sample means .... ive got the formula correct, but im just trying to review how to plug in the given data

Answer 13

wouldnt the sample means of the two populations which is 34.6 plug into m or no

Answer 14

as is, id say we go with:

\[(\bar x-\bar y) \pm z_{95\%}(standard~deviation)\]

since they seem to have already calculated it for us

Answer 15

34.6 + 1.96(11.9)
34.6 - 1.96(11.9)

Answer 16

11.28 , 57.92

Answer 17

do i add 34.6 together first or mutiply 1.96 and 11.9

Answer 18

A.between -23.8 and +23.8
B.between -35.7 and +35.7
C.between -45.4 and +45.
D.between -69.2 and +69.2
E.between -103.8 and +103.8

Answer 19

idk those were the answer choices...

Answer 20

i got the same thing you did though

Answer 21

hmmm, then my thought needs some revision with the info provided

Answer 22

The difference between the sample means of two populations is 34.6, and the standard deviation of the difference between sample means is 11.9. What is the 95% confidence interval?

Answer 23

so you dont have to scroll up and down (:

Answer 24

the mean given is 34 but the intervals are centered about zero

Answer 25

isnt there a calculator to plug this stuff in on the computer?

Answer 26

and then it gives you the answer someway

Answer 27

when we "move" the set we found to a mean of zero, we get +- 23

Answer 28

ohhh i see

Answer 29

thats just about one of the answers to

Answer 30

what about .8

Answer 31

as an educated guess, id say A is prolly correct due to some approximation errors

Answer 32

alright, thank you for taking the time and helping me (:

Answer 33

good luck :)

Answer 34

hell ya thank yaw

Answer 35

ITS A