Question

wewe mwy atuties for randomly selected weights of newtom gre 175.233.29, 7919 Construita contence to the new scorer very own terval 319 349g with only 18 sample values, 33.4 hg, and 3.0? What is the confidence interval for the population mean? - Mound to one decimal place is needed)

Answer 1

Solution:

Confidence interval for Population mean is given as below:

Confidence interval = Xbar ± t*S/sqrt(n)

From given data, we have

Xbar = 33.2

S = 7.9

n = 175

df = n – 1 = 174

Confidence level = 90%

Critical t value = 1.6537

(by using t-table)

Confidence interval = Xbar ± t*S/sqrt(n)

Confidence interval = 33.2 ± 1.6537*7.9/sqrt(175)

Confidence interval = 33.2 ± 0.9875

Lower limit = 33.2 - 0.9875 = 32.2

Upper limit = 33.2 + 0.9875 = 34.2

Confidence interval = (32.2, 34.2)

32.2 hg < µ < 34.2 hg

The above result is not very different from the given interval, 31.9 hg < µ < 34.9 hg, because the interval 32.2 hg < µ < 34.2 hg included in that interval.