Work for (a), (b), (c), (d) and (e):
a) Variance represents the average of the squared difference from the mean. Variance 0 means all values are same as mean which i...
Answer all 25 questions. Make sure your answers are as complete as possible.
Show all of your work and reasoning. In particular, when there are
calculations involved, you must show how you come up with your answers
with critical work and/or necessary tables. Answers that come straight fromprograms or software packages will not be accepted.
Record your answers and work on the separate answer sheet provided.
This exam has 250 total points.
You must include the Honor Pledge on the title page of your submitted finalexam. Exams submitted without the Honor Pledge will not be accepted.
1. True or False. Justify for full credit. (25 pts)
(a) The normal distribution curve is always symmetric to its mean.
(b) If the variance from a data set is zero, then all the observations in this data set areidentical.(c) .ofcomplementtheis where,1)AND(AAAAPcc(d) In a hypothesis testing, if the p-value is less than the significance level a, we do nothave sufficient evidence to reject the null hypothesis.(e) The volume of milk in a jug of milk is 128 oz. The value 128 is from a discrete dataset.
Refer to the following frequency distribution for Questions 2, 3, 4, and 5. Show all work. Just theanswer, without supporting work, will receive no credit.
A random sample of 25 customers was chosen in UMUC MiniMart between 3:00 and 4:00PM on a Friday afternoon. The frequency distribution below shows the distribution forcheckout time (in minutes).
Checkout Time (in minutes)
1.0 – 1.9
2.0 – 2.9
3.0 – 3.9
4.0 – 5.9
2. Complete the frequency table with frequency and relative frequency. (5 pts)
3. What percentage of the checkout times was less than 3 minutes? (5 pts)
4. In what class interval must the median lie? Explain your answer. (5 pts)
5. Assume that the largest observation in this dataset is 5.8. Suppose this observation wereincorrectly recorded as 8.5 instead of 5.8. Will the mean increase, decrease, or remainthe same? Will the median increase, decrease or remain the same? Why? (5 pts)
6. A random sample of STAT200 weekly study times in hours is as follows:
2 15 15 18 30
Find the sample standard deviation. (Round the answer to two decimal places. Show all work.Just the answer, without supporting work, will receive no credit.) (10 pts)
image501Refer to ...