Week5 Stat 200
15. You take a sample of 22 from a population of test scores, and the mean
of your sample is 60. (a) You know the standard deviation of the population
is 10. What is the 99% confidence interval on the population mean. (b) Now
5. At a school pep rally, a group of sophomore students organized a free raffle for prizes. They claim that
they put the names of all of the students in the school in the basket and that they randomly drew 36 names
out of this basket. Of the prize winners
Page 1 of 3
Homework Assignment Week #8
#12: What are the two components of the total sum of squares in a one-factor between-subjects
Sum of Square treatment & Sum of Square error
#13: How is the mean square com
18. You choose an alpha level of .01 and then analyze your data.
a. What is the probability that you will make a Type 1 error given that
the null hypothesis is true?
.01 because the alpha level is by definition the probability of the type
error given that
February 2, 2016
Week 1 Homework
6. Categorize the following variables as being qualitative or
Rating of the quality of a movie on a 7-point scale Quantitative
Age - Quantitative
Country you were born in - Qualitative
UMUC STAT200 Summer 2017
Homework 4 Solution
a. Z score=
= -0.75 We get P= .2266
b. Z score =
= -2.625, we get P =.0043
c. For P= 0.9, Z score = 1.28, 1.28 =
New speed limit= 81.25
d. It is possible th
STAT 200 QUIZ 2
Instructor: Dr. Jing Gao
The quiz is worth 80 points total.
The quiz covers week 3, week 4 and week 5 materials.
The quiz has two portions:
Multiple Choice (8 problems, 32 points). Show work/expla
UMUC STAT200 Summer 2017
Homework 2 Solution
page 159 (2 points)
The median is the 2nd quartile, 5th decil
1. True or False. Justify for full credit.
(a) If all the observations in a data set are identical, then the variance for this data set is zero. (b)
If A and B are disjoint, P(A) = 0.4 and P(B) = 0.5, then P(A AND B) = 0.2. (c) The mean is
always equal to
STAT200 Homework for week 5
Question 1 Every applicant for the open position took a test. Results of the test are close to the
Normal distribution with mean = 200 and standard deviation =50.
Company decided to call for interview applicants whos test score
Week 4 Homework
For this HW you should use Appendix Table for Normal Distribution
Problem 1. Normal Distribution has mean 80 and a standard deviation = 20.
Calculate the z-scores for the following x-values:
a) x = 50
b) x = 90
c) x = 120
Quiz 3 Summer 2017 Statistics 200
There are five (5) problems on this quiz on four (4) pages. Problems 1-3 are worth
20 points, with problems 4-5 worth 10 points each for a total of 80 points. Show all
work, as it is important for me to see the method and
Homework Assignment Week 6
Lane ch11, q18.
You choose an alpha level of .01 and then analyze your data.
a. What is the probability that you will make a Type I error given that the
null hypothesis is true?
Probability of a Type 1 error = 0.01 or 1%
Home Work Assignment Week 5
Why is a 99% confidence interval wider than a 95% confidence interval?
A 99% confidence interval is wider than a 95% confidence interval, because of the larger
parameter/interval of numbers a 99% confidence interv
Each question is worth 1 point.
Dont leave anything blank. I can always find a way to give you some credit if youve made an
attempt. Be sure to post any questions you have after the answers open.
The work you turn in by 11:59 P.M. on July 2nd must
Answers for Quiz 2
1. a) (12/52)(11/51) = 0.04978
b) (13/52)(12/51) = 0.05882
3. a) If the class is a sample from a population of classes then it is a statistic.
b) If the class is considered the whole population then it is a paramet
Homework Week 6
11-18 a) 0.01
12-13 a) t = 2.57 p = 0.0175 yes, significant
b) t = 1.82 p = 0.099 no, not significant
9-77 Ho: 4.5
Ha: > 4.5
n = 49 x = 5.1 s.d. = 1.2
Use Students t = 3.5
P = 0.0005 (one tailed)
UMUC STAT 200
Quiz 2 Earned a grade of 96. Beware of question 31and 33
1. (1) The singular form of the word dice is die. Tom was throwing a six-sided die.
The first time he threw, he got a three; the second time he threw, he got a three again.
Whats the p
Homework Assignments - Week 4
Lane ch7.q8. Assume the speed of vehicles along a stretch of I-10 has an
approximately normal distribution with a mean of 71 mph and a standard deviation
of 8 mph.
a. The current speed limit is 65 mph. What is the proportion
Homework Week 4
a) 0.2266 of drivers are less than or equal to the speed limit.
b) 0.0043 of drivers are going below 50 mph.
Type equation here . c) The new speed limit would be 81.25 mph, or just 81 mph by
d) Positively skewed.
Homework Week 2
large positive skew: B
Large negative skew: C
Can determine median, trimean, interquartile range, and range
Mean = 39.75
I know I dont need to remind anyone that UMUCs academic integrity policies. We are all
adults. We know that we shortchange only ourselves if we arent honest. This quiz needs to be
completed without help from others. The work submitted must be your
Home Work Assignments Week 2
7. For the data from the 1977 Stat. and Biom. 200 class for eye color, construct:
a. pie graph
b. horizontal bar graph
c. vertical bar graph
d. a frequency table with the relative frequency of each eye color
Home Work Assig
Home Work Assignments Week 3
Lane ch5.q7.You flip a coin three times.
(a) What is the probability of getting heads on only one of your flips? Flipped 3, so 3 out of 8,
(b) What is the probability of getting heads on at least one flip? 7 out of 8, 7/8
Answers to Quiz 1
3. Ordinal (or ratio if you thought grades were numbers rather than A, B, C),
ratio, nominal, interval
4. Convenience, random, systematic, cluster
5. a. 4
b. 3.5 7.5 11.5 15.5
c. 1.5 5.5 9.5 13.5 17.5
d. Histogram graphs have b
1. A fair coin is flipped 9 times. What is the probability of getting exactly 6 heads?
1/ (2^9) x (9/6)2^9 = 512(9 x 8 x 7) / (3 x 2 x 1) =8484/512 = 0.1640625 x 100 = 16.4%
2.You flip a coin three times.
(a) What is the probability of getting heads on on