The Wisconsin Dairy Association is interested in estimating the mean weekly consumption of milk for adults over the age of 18 in that state.To do this,they have selected a random sample of 300 people from the designated population.The following results were recorded: Given this information,if the leaders wish to estimate the mean milk consumption with 90 percent confidence,what is the approximate margin of error in the estimate?
A)z = 1.645
B)±12.996 ounces
C)±0.456 ounce
D)±0.75 ounce

Question

The Wisconsin Dairy Association is interested in estimating the mean weekly consumption of milk for adults over the age of 18 in that state.To do this,they have selected a random sample of 300 people from the designated population.The following results were recorded:  Given this information,if the leaders wish to estimate the mean milk consumption with 90 percent confidence,what is the approximate margin of error in the estimate?
A)z = 1.645 
B)±12.996 ounces 
C)±0.456 ounce 
D)±0.75 ounce

Quizplus · Accepted Answer

The formula for calculating the margin of error for the mean with a known population standard deviation is:
Margin of error = z* (sigma/sqrt(n))

Here, we are given the following information:
- Sample size (n) = 300
- Population standard deviation (sigma) = 4 ounces (given in the question)
- Confidence level = 90%, which corresponds to a z-value of 1.645 (from the standard normal distribution table)

Substituting these values in the formula, we get:
Margin of error = 1.645 * (4/sqrt(300))
= 0.75 ounces (rounded to two decimal places)

Therefore, the approximate margin of error in the estimate is ±0.75 ounce. Option D is correct.

The Wisconsin Dairy Association Is Interested in Estimating the Mean