Question

Can you help me

Answer 1

You have data from a sample of 80 workers at a local factory who are full time employees. The mean systolic blood pressure of this sample 130. You know that the population standard deviation (σ) of all workers' systolic blood pressure at the local factory is 15.



Which of the below represents a 95% confidence interval for the unknown population mean systolic blood pressure of local factory workers who are full time employees.

(hint: since the population standard deviation (σ) is known, you can use the z-distribution for your confidence interval construction.)

Select one:
A. [126.71 – 133.29]
B. [121.25 – 131.19]
C. [125.68 – 134.32]
D. [127.24 – 132.76]
E. [129.83 – 131.15]

Answer 2

@Kittykatiehunt

Answer 3

i dont have much knowledge on this sorry

Answer 4

@jdoe0001

Answer 5

Not my area of expertise.
@Hayhayz
@KamiBug

Answer 6

I don't know :/

Answer 7

I don't know how to do this. I'm so sorry but I can tag people who might be able to help.
@Directrix @MissSmartiez @gottennis121 @HannahA @Mythorius @Dani_Rose

Answer 8

Good Luck Love! <3 @toxicsugar22

Answer 9

sorry miha, I have no idea :/

Answer 10

*mija

Answer 11

http://www.stat.yale.edu/Courses/1997-98/101/confint.htm

Answer 12

@kropot72

Answer 13

The confidence interval is:
\[\large C.I.=(\bar{x}-1.96\frac{\sigma}{\sqrt{n}},\ \bar{x}+1.96\frac{\sigma}{\sqrt{n}})\]

Answer 14

So is it A. [126.71 – 133.29]

Answer 15

Correct.

Answer 16

I'll try.

Answer 17

For a 99% confidence interval Z = 2.576. (In the previous question, for a 95% confidence interval Z = 1.96). Therefore use the previous equation, but change 1.96 to 2.576.

Answer 18

Yes, you are correct again.

Answer 19

You're welcome :)