The percent defective for parts produced by a manufacturing process is targeted at 4%. The process is monitored daily by taking samples of sizes n = 160 units. Suppose that today%u2019s sample contains 14 defectives. How many units would have to be sampled to be 95% confident that you can estimate the fraction of defective parts within 2% (using the information from today%u2019s sample--that is using the result that ?

A sample of 767 is needed.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of , and a confidence level of , we have the following confidence interval of proportions.

In which

z is the zscore that has a pvalue of .

The margin of error is given by:

For this problem, we have that:

14 defectives out of 160, so

95% confidence level

So , z is the value of Z that has a pvalue of , so .

How many units would have to be sampled to be 95% confident that you can estimate the fraction of defective parts within 2% of the percentage?

We would need a sample of n.

n is fround when .  So

Rounding up

A sample of 767 is needed.

answer: i think the answer is etheir c or d but i don't know which one but have a good day!

step-by-step explanation:

4400

step-by-step explanation: