New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Exam 1guide


Exam 1guide MATH 2311


Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Intro To Prob & Statistics
Leticia Reza
75 ?




Popular in Intro To Prob & Statistics

Popular in Mathematics (M)

This 8 page Bundle was uploaded by on Monday December 21, 2015. The Bundle belongs to MATH 2311 at University of Houston taught by Leticia Reza in Fall 2015. Since its upload, it has received 259 views. For similar materials see Intro To Prob & Statistics in Mathematics (M) at University of Houston.


Reviews for Exam 1guide


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 12/21/15
Math 2311 Written Homework 2 (Sections 1.5 & 2.1) Name:___Giang Tran________________________ PeopleSoft ID:_1372369___________ Instructions:  Homework will NOT be accepted through email or in person. Homework must be submitted through  CourseWare BEFORE the deadline.  Print out this file and complete the problems.    Use blue or black ink or a dark pencil.  Write your solutions in the space provided.  You must show all work for full credit.  Submit this assignment at  under  "Assignments" and choose whw2. 1. Section 1.5, Problem 2 a. - The distribution of data is skewed left because the mean is smaller than the median (mean=74.71 < median= 76.00) - Possible outliers: IQR= Q3 – Q1= 84 – 68 = 16 1.5IQR = 24 => Outlier boundaries: [Q1 – 1.5IQR, Q3 +1.5IQR] = [68 – 24, 84 -24]= [44,108] => This data has an outlier, which is 35 - The middle 50% lies between 68 and 84, which locates at the median 76 - Range = Max – Min = 94 – 35 = 59 b. Construct boxplot 2. Using the data called SAT in the mosaic Data package, create boxplots for both the math and verbal  score variables.  Write one to two sentences comparing those scores.  For math score variables: > fivenum(~math,data=SAT) [1] 443.0 474.0 497.5 540.0 592.0 > bwplot(~math,data=SAT)  For verbal score variables: > fivenum(~verbal,data=SAT) [1] 401 427 448 491 516 > bwplot(~verbal,data=SAT) => Both math and verbal scores’ distributions are skewed right The math scores are generally higher than verbal scores And the math scores have a wider range (thus more variable) than the verbal  scores 3. Section 2.1, Problem 12 > choose(8,4) [1] 70 8C 4 = 70 There are 70 ways to form a committee of 4 from a group of 8 people 4. Section 2.1, Problem 18 > choose(8,2) [1] 28 > choose(6,2) [1] 15 > choose(8,2)*choose(6,2) [1] 420 To draw 2 white marbles from 8 white marbles, we8C2 = 28 ways To draw 2 black marbles from 6 black marbles, w6Ch2 = 15 ways  To draw the 4 marbles so that 2 will be white and 2 will be black, we have 8C 2  x 6C 2 = 28 x 15 = 420 ways 5. Section 2.1, Problem 22 > factorial(4) [1] 24 > factorial(6) [1] 720 > factorial(4)*factorial(6) [1] 17280 To arrange the tallest 4 in the back, we have 4! = 24 ways To arrange the rest of people, we have (10­4)! = 6! = 720 ways  So, for a group of 10 people to line up for a picture so that the tallest 4 stand in the back, we have 4! x (10 – 4)! = 24 x 720 = 17280 (ways) Math 2311 Written Homework 4 (Sections 3.1­3.3) Name:___Giang Tran___________________________ PeopleSoft ID:_1372369________ Instructions:  Homework will NOT be accepted through email or in person. Homework must be submitted through  CourseWare BEFORE the deadline.  Print out this file and complete the problems.    Use blue or black ink or a dark pencil.  Write your solutions in the space provided.  You must show all work for full credit.  Submit this assignment at  under  "Assignments" and choose whw4. 1. Section 3.1, Problem 4  Mean of X: > 1*(.15)+2*(.2)+3*(0.1)+4*(.2)+5*(.1)+6*(.15)+7*(.1) [1] 3.75 So, mean of X is 3.75 2. Section 3.1, Problem 10 Portfolio A: Var (A) = E(A ) ­ E(A)2 =  > (-1500*-1500*.2+-100*-100*.1+500*500*.4+1500*1500*0.2+3500*3500*0.1)-(-1500*.2+- 100*.1+500*.4+1500*0.2+3500*0.1)*(-1500*.2+-100*.1+500*.4+1500*0.2+3500*0.1) = 1934400  Standard deviation of Portfolio A =  square root of Var(A) = 1390.83 Portfolio B:  2 2 Var (B) = E(B ) ­ E(B) = > (-2500*-2500*.2+-500*-500*.1+1500*1500*.3+2500*2500*.3+3500*3500*.1)-(-2500*.2+- 500*.1+1500*.3+2500*.3+3500*.1)*(-2500*.2+-500*.1+1500*.3+2500*.3+3500*.1) = 4050000  Standard deviation of Portfolio B =  square root of Var(B) = 2012.46 So, these standard deviations contradicts answer for problem 9, which says it is better to choose Portfolio B (since “Standard deviation of Portfolio B” is greater than “Standard deviation of Portfolio A”, so Portfolio B  have more variations from the mean than Portfolio A) 3. Section 3.1, Problem 20 Mean (X)  -1*.3+0*.1+1*.5+2*.1 = 0.4 Variance (X= > (-1*-1*.3+0*0*.1+1*1*.5+2*2*.1)-(-1*.3+0*.1+1*.5+2*.1)*(-1*.3+0*.1+1*.5+2*.1)= 1.04 Standard deviation (X) = square root of Variance (X) = 1.02 So, we have:  Mean (W) = Mean (3+2X) = 2 Mean (X) +3 = 2*.4 + 3= 3.8 Variance (W) = Variance (3+2X) = 2  Variance (X) = 4.16 Standard deviation (W) = square root of Variance (W) = 2.04 4. Section 3.2, Problem 10 a. Proportion of groups will exactly four of the six households have a DVD player P(X=4) = > dbinom(4,6,.9)= 0.098415 b. Proportion of groups will at most two of the households have a DVD player P(X<=2) =   > pbinom(2,6,.9) = 0.00127 5. Section 3.2, Problem 14 a. Probability that exactly 2 have never been married P(X=2)  = > dbinom(2,10,.2)= 0.3019899 b. Probability that at most 2 have never been married P(X<=2)  = > pbinom(2,10,.2)= 0.6777995 c. Probability that at least 8 have been married = Probability that at most 2 have never been married = 0.6777995 6. Section 3.2, Problem 16 a. The probability that exactly five complete the program P(X=5) = dbinom(5,7,.7) = 0.3176523 b. The probability that five or more complete the program P(X>=5) = 1 – P(X<5) = 1 – P(X<=4)           =  1-pbinom(4,7,.7) = 0.6470695 c. The average number of people out of the seven that went to the training that will complete the program E(X) = np = 7*.7 = 4.9 ~ 5 people  7. Section 3.3, Problem 8 a. The probability that the quarterback throws 3 incomplete passes before he has a completion P(X=4)= dgeom(3,.44) = 0.07727104 b. The number of passes can the quarterback expect to throw before he completes a pass E(X)= 1/p= 1/.44= 2.272727 c. The probability that it takes more than 5 attempts before he completes a pass P(X>5)= 1­ P(X<=5) = 1-pgeom(4,.44)= 0.05507318 d. The probability that he attempts more than 7 passes before he completes one P(X>7)= 1­ P(X<=7) =  1-pgeom(6,.44)= 0.01727095 8. Section 3.3, Problem 10 a. The probability that she sells more than 20 policies P(X>20) = 1 – P(X<=20) = 1-pbinom(20,120,.15)= 0.2556828 b. The expected number of policies she sells E(X) = np = 120*.15 = 18


Buy Material

Are you sure you want to buy this material for

75 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Amaris Trozzo George Washington University

"I made $350 in just two days after posting my first study guide."

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Parker Thompson 500 Startups

"It's a great way for students to improve their educational experience and it seemed like a product that everybody wants, so all the people participating are winning."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.