Answer:
A. 0.009899
B. 0.005624
Step-by-step explanation:
Data:
Let the probability that an item is defective =
The probability that the item is not defective =
The probability that the fifth item is defective =
= 0.009899
Probability that one in 5 items is defective = 0.005624
Answer:
The 95% margin of error for this estimate is 0.0274 = 2.74 percentage points.
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:
95% confidence level
So , z is the value of Z that has a pvalue of
, so
.
72% of Americans said that they had at least one credit card
This means that
Give the 95% margin of error for this estimate.
The 95% margin of error for this estimate is 0.0274 = 2.74 percentage points.