# FSSC Probability Model and Decimal Places Discussions

3/6/22, 8:17 AMTopic: Discussion #7 (in preparation for the Midterm Exam)

This is a graded discussion: 10 points possible

due Mar 6

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Discussion #7 (in preparation for the Midterm Exam)

12

This discussion is based on topics you may find in the Midterm Exam. Please review the STA2023 Midterm Exam Study

Guide before you answer this question set.

Each question is worth 1 point.

1. What percent of the measurements are found below the 30th percentile? Found above the 30th percentile?

2. How do you find the IQR for a data set? Explain the process and provide the formula for the IQR

3. For the regression line

, what is the best predicted value if x is 7?

4. Provide the formula to calculate a residual and explain what a residual tells us for any ordered pair (x,y).

5. Assume that male and female births are equally likely and that the birth of any child does not affect the probability the gender of

any other children. Find the probability of at most three girls in ten births. In this problem, which function do you use in TI 84

calculator? (binompdf or binomcdf)?

6. An unusual event is an event in which the probability exceeds 1. (True or False)

7. The least squares regression line maximizes the sum of the squared residuals SSR. (True or False?)

8. The ” mean” is considered to be a measure of dispersion? (True or False)

9. The following formula calculates a z-score:

(True or False)

10. A quiz consists of 100 multiple choice questions. Each question has 4 possible answers (A-D) and only one answer is correct. If

the student guesses the answer to the questions, then what is the probability earn a grade of 70% or higher?

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Discussion#5 (probability)

It is recommended that you complete this week’s MyLab Math assignments before you

submit this assignment.

For each discussion, students will post their answers to the question set.

1. A box contains six 25-watt light bulbs, nine 60-watt light bulbs, and five 100watt light bulbs. What is the probability of randomly selecting a 60-watt light

bulb? (2 pt) Note: You must provide your answer as a fraction.

2.

Cell Phone Provider

Probability

AT&T

0.271

Sprint

0.236

T–Mobile

0.111

Verizon

0.263

3. Does above table represent the probability model? Explain your answer. (3 pt)

4. The data shows the distance that employees of a certain company travel to

work. One of these employees is randomly selected. Determine the

probability that the employee travels between 10 and 29 miles to work. (2 pts)

Distance

(miles)

Number of

employees

0–9

124

10 – 19

309

20 – 29

257

30 – 39

78

40 – 49

2

5. In Q3, Is the probability the employee travels between 40 and 49 miles to

work considered to be unusual? Explain your answer. (3 pt)

Discussion #6 (discrete probability

distributions)

It is recommended that you complete this week’s MyLab Math assignments before you

submit this assignment.

For each discussion, students will post their answers to the question set.

Each question is worth 2 points

Q1. Determine whether the random variable is discrete or continuous.

The number of songs on an MP3 player. (Discrete/Continuous)

Q2. Which of the following probability experiments represents a binomial experiment?

A. Asking 50 adults the amount of their last cell phone bill

B. Asking 10 prisoners the number of crimes for which they were convicted

C. Asking 20 students the name of their favorite television show

D. Asking 30 homeowners if they would favor a new tax to support education

Q3. Forty-three percent of marriages end in divorce. You randomly select 15 married

couples. Find the expected number of marriages that will end in divorce.

Q4. x represents the number of computers in a household. Find the expected value of x

(aka the mean) and the standard deviation of the number of computers in a household.

x

P(x)

0

0.15

1

0.45

2

0.30

3

0.10

Q5. Suppose an exam consisted of 10 multiple choice problems, each with five possible

responses (A-E), only 1 of which is correct. If a student randomly guesses the answers to

each question then what is the probability that a student guesses the correct answer to

exactly 7 questions? Additionally, what is the probability that a student passes the exam

with a score of 70% or higher? (round to 5 decimal places)