A manufacturer wants to estimate the proportion of defective items that are produced by a certain machine. a random sample of 50
items is selected. which excel function would not be appropriate to construct confidence interval estimate?a. Countifb. Norm.s.invc. Stdevd. all of these answer are correct
Excel stdev function is not appropriate to construct confidence interval estimate, because the estimation of the proportion of defective items that are produced by a certain machine has binomial distribution.
stdev fuction is used for calculating standard deviations where sample has more than two different values. (multinomial)
Norm.s.inv function calculates inverse of the standard normal cumulative distribution, and countif counts the number of cells that meet a criterion. Both functions are used to construct confidence interval estimate
