A poll was conducted that asked 1015 people how many books they had read in the past year. Results indicated that x-bar= 12.3 books and s=16.6 books. Construct a 95% confidence interval for the mean number of books people read.

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Formula:

CI95 = mean ± 1.96 (sd/√n)
...where ± 1.96 represents the 95% interval using a z-table, sd = standard deviation, and n = sample size.

n = 1015
mean = 12.3
sd = 16.6

Plug values into the formula and determine the upper bound (+) and lower bound (-).

I'll let you take it from here.

Thanks!!!!!!!!!

Got it thanks!

Sure, I can help you with that!

To construct the confidence interval for the mean number of books people read, we can use the formula:

CI = x̄ ± (Z * (s / √n))

Where:
CI is the confidence interval
x̄ is the sample mean (12.3 books)
Z is the Z-score corresponding to the desired confidence level (95% confidence level corresponds to Z = 1.96)
s is the sample standard deviation (16.6 books)
n is the sample size (1015 people)

Now, let's plug in the values:

CI = 12.3 ± (1.96 * (16.6 / √1015))

To compute the confidence interval, we need to find the standard error (SE) first, which is equal to (s / √n):

SE = 16.6 / √1015 ≈ 0.520

Plugging in the values, we get:

CI = 12.3 ± (1.96 * 0.520)

Now, let's calculate the lower and upper bounds of the confidence interval:

Lower bound = 12.3 - (1.96 * 0.520)
Upper bound = 12.3 + (1.96 * 0.520)

Lower bound ≈ 11.28
Upper bound ≈ 13.32

Therefore, the 95% confidence interval for the mean number of books people read is approximately (11.28, 13.32).