#### (Solved): WPC 300 : Quiz 4: Inferential ...

Quiz 4: Inferential

Score 10 out of 10

Question 1          1 pts

The WPC Sports Company has noted that the size of individual "customer order" is normally distributed with a mean of \$100 and a standard deviation of \$12. If a soccer team of 16 players were to make the next batch of orders, what would be the standard error of the mean?

• 3.00
• 3.46
• 4.00
• 10.00

Question 2           1 pts

When sample size increases

• Standard deviation of the sample mean increases
• Confidence interval increases
• Confidence interval remains the same
• Confidence interval decreases

Question 3          1 pts

Which of the following is a Type-I error?

• The null hypothesis is actually true, but the hypothesis test incorrectly rejects it.
• The null hypothesis is actually true, and the hypothesis test correctly fails to reject it.
• The null hypothesis is actually false, but the test incorrectly fails to reject it.
• The null hypothesis is actually false, and the test correctly rejects it.

Question 4              1 pts

What is the confidence level when the level of significance is 0.07?

• 0.970
• 0.930
• 7%
• 0.093

Question 5          1 pts

Which of the following is a continuous random variable?

• The number of new hires in a year
• The number bounced check from a bank
• The time to complete a specific task
• The outcomes of rolling two dice

Question 6              1 pts

Which of the following is a difference between the t-distribution and the standard normal (z) distribution?

• The standard normal distributions' confidence levels are wider than those of the t-distribution
• The t-distribution cannot be calculated without a known standard deviation, while the standard normal distribution can be.
• The t-distribution has a larger variance than the standard normal distribution
• The standard normal distribution is dependent on parameters like degree of freedom, while t-distribution is not.

Question 7     1 pts

The central limit theorem states that even if the population is not normally distributed, the

• Mean of the population can be calculated without using samples
• Standard error of the mean will not vary from the population mean
• distribution of the sample mean will still be normal when the sample size is large
• Sampling distribution of the mean will vary from the sample to sample

Question 8         1 pts

Which of the following proposition describes an existing theory or belief?

• Null hypothesis
• Proportion
• Alternative hypothesis
• Standard deviation

Question 9            1 pts

In order to reject the null hypothesis, the p-value must be less than the

• Variance
• Alpha
• Degrees of freedom
• Standard deviation

Question 10          1 pts

You are collecting data via an online survey to improve education standard at ASU. Which of the following methods will not result in data collection bias?