Assume that the heights of bookcases are normally distributed. a random sample of 16 bookcases in one company have a mean height of 67.5 inches and a standard deviation of 3.6 inches. construct a 99% confidence interval for the population standard deviation, σ.

Step-by-step explanation:

Given :  Confidence level :

Significance level :

Sample size : n= 16

Sample standard deviation : s= 3.6 inches

Using chi-square distribution table , the critical values are:

We know that , confidence interval for the population standard deviation is given by :-  

Hence ,  a 99% confidence interval for the population standard deviation is .

b

step-by-step explanation:

answer:   (s+1)(s+4)

step-by-step explanation:

factor s2+5s+4

s2+5s+4

=(s+1)(s+4)