Bones Brothers & Associates prepare individual tax returns. Over prior years, Bo
ID: 3201822 • Letter: B
Question
Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers has maintained careful records regarding the time to prepare a return. The mean time to prepare a return is 90 minutes and the standard deviation of this distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed regarding the preparation time. What assumption do you need to make about the shape of the population distribution of all possible tax preparation times to make inferences about the mean time to complete a tax form? The population distribution is skewed to the right. The shape of the population distribution does not matter. The population distribution is skewed to the left. The population distribution is normal.
Explanation / Answer
we have sample size as n>30 large sample.
here n=100
As the size of the sample increases, what happens to the shape of the distribution of sample means?
It approaches a normal distribution
The population is assumed to be normally distributed as is generally the case. If the sample size is large enough, the sampling distribution will also be nearly normal. If this is the case, then the sampling distribution can be totally determined by two values - the mean and the standard deviation.
The population distribution is normal.