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Example probability Question - MyMathLab homework

Qn8. A group of students were asked if they carry a credit car.. The responses are listed in the table.
contigency table probability.png
If a student is selected at random, find the probability that he or she is a sophomore given that the student owns a credit card. Round you answers to three decimal places.
Qn9. A card is selected at random from a standard deck of 52 playing cards. Find the probability of each event.
a. Randomly selecting a black suit or a jack.
b. Randomly selecting a heart or an 8
c. Randomly selecting 1 10 or face card.
Q10. The accompanying table shows the numbers of male and female students in a particular country who received bachelor’s degrees in business in a recent year. Complete parts (a) and (b) below.
business graduates probability.png
Find the probability that a randomly selected student is male, given that the student received a business degree.

Example questions from probability unit
A card is drawn from a standard deck of 52 playing cards. Find the probability that the card is an ace of a black card.

The table lists the smoking habits of a group of college students.
probability table.png
If a student is chosen at random, find the probability of getting someone who is a man or a non-smoker. Round you answer to three decimal places.

Use the frequency distribution to the right, which shows the number of voters (in millions) according to age, to find the probability that a voter chosen at random is in the given age range.

probability table.png
The probability is..

Qn6. You are planning a three-day trip to Seattle, Washington, in October. Use the fact that on each day, it could either be sunny or rainy, and that each day is equally likely to be sunny of rainy to answer the following question.
What is the probability that it rains on at least one day?

MyMathLab Homework 5.5 Answers
A drug tester claims that a drug cures a rare skin disease 78% of the time. The claim is checked by testing the drug on 100 patients. If at least 73 patients are cured, the claim will be accepted.

Find the probability that the claim will be rejected assuming that the manufacturer's claim is true. Use the normal distribution to approximate the binomial distribution if possible.

Solving the question

The first step for solving this question is to check that the conditions for normal to binomial approximation are met.,
np >= 5, and nq >= 5

In this case the conditions are met because np; 1000.78 = 78 , & nq = 0.22100 = 22
q = 1-p; = 1-0.78 = 0.22
To use the normal approximation , we need to calculate the mean and standard deviation based on the data given.
np = 1000.78 = 78, and standard deviation sqrt(npq) = sqrt(0.780.22*100) = 4.142

We are interested in the probability that 1-p(X < 73)
We'll use continuity correction to improve the accuracy of our calculations.
Therefore, we'll find p(X < 72.5)

The probability will be rejected if the value is less than 73.
P(X < 73) = (72.5 - 78)/4.142 = -1.33
P(X < -1.33) = 0.0921.,

Note that you can also use Excel to answer this question,
the function; =NORM.DIST(72.5,78,4.142,TRUE) is very helpful when dealing with such kinds of questions.

You are free to contact MyMathLab Homework Help in case you need help in answering similar questions.

DS 123 Statistical Analysis

Assignment 4 instructions

This Assignment consists of two parts: Part 1 includes questions from textbook, and Part 2 is application using JMP. In total, you will be creating 2-3 files for this assignment. For Part 1 you will create either Word file or Excel file (see details below). For Part 2, you will have 1 JMP report files. Hence, you need to submit your all the files in a single attempt. You may submit multiple attempts if you make corrections. But, note that each attempt should contain all files. (Total 20pts)

Part 1. (20pts)

  1. Work on the following problems from the textbook. Clearly indicate how you arrived to solution. You need to show your work to earn credit.
  2. You may solve questions by calculator (not using Excel). Then, use Word document to write down answers. Label question numbers clearly and do not forget to write down your name and section number.
    o You may submit handwritten paper, but make sure it is eligible to read and all the problems should be in a single document (do not submit separate files for each question)
  3. You may also solve questions using Excel/JMP. In this case, submit your Excel file or copy/paste output of JMP file in Word document. Again, make sure to label question numbers and answers clearly. You may use similar template provided in previous assignment.

Question sets:
11.2, 11.4, 11.6

Part 2. (5pts- Extra Credit)
• Use JMP to Conduct ANOVA. Follow instructions indicated in document files named “Using JMP to Conduct Analysis of Variance” (or click here

STAT 170 – Elementary Statistics Quantitative Reasoning Project
Use the following steps to test hypotheses about your statistics project.

When the problem involves hypothesis testing, use the following structure for written reports.
• Step 1: State the hypotheses.
• Step 2: Summarize the data for your readers.
• Step 3: Give the value of the test statistic and the p-value.
• Step 4: Use the p-value to draw a conclusion. State the conclusion in statistical
terms: Reject Ho in favor of Ha, or retain Ho (fail to reject Ho).
• Step 5: State the conclusion in layman terms and in context of the application. Use the
p-value to state the strength of the evidence.
• p-value > .10
retain Ho – there is insufficient evidence to reject Ho in favor of Ha
• .05 < p-value ≤ .10
gray area -- decision to reject Ho or retain Ho is up to the investigators – there is some
evidence against Ho and in support of Ha
• .01 < p-value ≤ .05
reject Ho in favor of Ha – there is fairly strong evidence against Ho and in favor of Ha
• .001 < p-value ≤ .01
reject Ho in favor of Ha – there is strong evidence against Ho and in favor of Ha
• p-value ≤ .001
reject Ho in favor of Ha – there is very strong evidence against Ho and in favor of Ha

Use your TI-83/TI-84 calculator for all of these problems. You will not need any tables.
Use the Sample Test 3 Questions—Answer Key (posted in Canvas) as an example of what my
expectations are.