Question

Suppose a sample of 80 with a sample proportion of 0.58 is taken from a population. Which of the following is the approximate 68% confidence interval for the population parameter?
A. (0.525, 0.635)
B. (0.470, 0.690)
C. (0.359, 0.801)
D. (0.414, 0.746)

Answer 1

what is the midpoints of each interval?

Answer 2

well, they all have the same midpoint so we cant narrow it by that.

Answer 3

what is the z score for 68%? and what is the standard error for the sample size?

Answer 4

its a complicated way to to do it and i don't have the right calculator for it

Answer 5

it can be done on a basic calculator, something with a square root

Answer 6

tell me the formula for the standard error

Answer 7

the approximation means that we will use the emipirical rule, maybe you know it as the 68-95-99 rule?

Answer 8

i just seen that

Answer 9

we should still know how to calculate for a standard error. once we know that this is pretty well answered.

Answer 10

thats just a picture of a dot ...

Answer 11

it wont let me put the picture

Answer 12

use your words ... type with your fingers

Answer 13

p+\[p \pm 1\times \sqrt{p(1-p)/n}\]

Answer 14

very good

lets just use one endpoint since all the solutons differ.

what is .58(.42)/80?

Answer 15

0.003045

Answer 16

now take the square root of that

Answer 17

0.05518151864528558

Answer 18

you do know where i got the values for p and n right?

now add that to .58

Answer 19

we only need 3 decimals so

.055 + .58 is our upper limit

Answer 20

0.635

Answer 21

then lets pick that one

Answer 22

i take it your done with this one ....

Answer 23

good luck