Question: Classmates Ken and John have been comparing their past exam performances. On 60% of the exams, Ken received a grade of B or better. John

Classmates Ken and John have been comparing their past exam performances. On 60% of the exams, Ken received a grade of B or better. John received a grade of B or better on 70% of the exams. They noticed that on 90% of the exams on which Ken scored B or better, John also made B or better.
a. What proportion of the time did both Ken and John score B or better?
b. Suppose you choose one of the exams at random. How likely is it that at least one of the two failed to score B or better?
c. If you choose an exam at random and learn that John scored a B or better, how likely is it that Ken did not?
d. Are John’s test performance and Ken’s test performance statistically independent? Explain how you reached your conclusion.

Step by Step Solution

★★★★★

3.31 Rating (151 Votes )

There are 3 Steps involved in it

1 Expert Approved Answer

Step: 1 Unlock

Event K Ken makes B or better P K 60 Event J John makes B or better P J 70 P J l K 90 a P ... View full answer

Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock

Step: 3 Unlock

Document Format (1 attachment)

486-M-S-P (2468).docx

120 KBs Word File

Students Have Also Explored These Related Statistics Questions!

How likely is it that the national debt will stop rising before 2020? Explain your answer.

If you end up suing, how likely is it that your case will actually go to trial? How long do you think it will take to obtain a final outcome in your case?

How likely is it that the Sampsons will achieve their financial goals now that they have captured them in a financial plan? What activity must they periodically undertake?

Needing help with page 9 (Section 3.33 - Cost of Capital Guide) Must be done on the Commonwealth Bank of Australia for 2017. any significant help would be much appreciated :) Happy to pay more for...

Chapter 7 Revising and Presenting Your Writing I'm not a very good writer, but I'm an excellent rewriter. James A. Michener Half my life is an act of revision. John Irving Getting Started INT RODU CT...

1-Please provide 5 cross-examination questions for: Chris Moss Dr. Gerry Stein Sydney Payne Terry Preece Leslie Brown Alex Lloyd 2-Explain why/how/if you would use exhibits A, B, C, and D. 3-What...

COMM 215: BUSINESS STATISTICS REVIEW PROBLEMS 1 Descriptive Statistics 1. The listing below gives the service window of A&W: 4.91 0.85 0.52 2.51 1.92 2.66 1.94 5.19 2.33 3.51 2.95 2.62 service times...

Needing ANSWERS ASAP! Starting at pg 34 - Labeled Graded Project 06155200: Graded Project Instructions & Worksheets 1 Lesson 1: Business, Accounting, and You PROJECT GOAL The goal of this graded...

This is designed to assess your ability to apply your research design and data analysis skills toward real world problems. A essay addressing the 4 parts below.: Research Question/Theory of...

I'm willing to take this before the 19th of may. PROFESSIONAL ISSUES When a company looks too good to be true, it usually is. ; i - I The Rise and Fall of Enron BY C. WILLIAM THOMAS f you''re like...

A current transformer having primary turns of 2400 and secondary turns of 20 is connected to a source of 400 V and an impedance of 4410 n. A CT has a primary winding induced voltage of 390 V and a...

Whats a good way to find prospects for your business?

Suppose the population of some species after t years is modeled by the function. What is the maximum rate of the population growth?

Suppose, you are a team of human resource consultants who have been hired by Carla Caruso, an entrepreneur, who has started her own interior decorating business, a highly competent and creative...

A shaft carries five masses A, B, C, D and E which revolve at the same radius in planes which are equidistant from one another. The magnitude of the masses in planes A, C and D are 50 kg, 40 kg and...

The data set "email50" is a subset of the "email" data set in the OpenIntro.org textbook. Each case is an email from David Diez's G mail account in the early months of 2012. David had 3,921 emails...

Betty Cooker runs a bakery in San Francisco that specializes in her famous Black Forest cakes. These cakes come with four kinds of frostings-Vanilla, Chocolate, Raspberry and Devilicious. She...

It is important to be able to recognize galvanic corrosion. In the following list of cases, explain whether galvanic corrosion is a probable cause of the corrosion. a. Steel rivets in aluminum drain...

Plaintiff drove a bus for defendant Diversified Paratransit, Inc., which was in the business of transporting developmentally disabled adults and children from their homes and care providers to...

Do you think you smell? If you falsely believe you emit an unpleasant, foul, or offensive body odor, you may suffer from olfactory reference syndrome (ORS). The disorder disables patients, who often...

Refer to the journal eCAM (November 2006) assessment of the quality of the methodology used in studies of the treatment for Alzheimers disease, presented in Exercise. Data on the quality of the...

In each case, find the approximate sample size required to construct a 95% confidence interval for p that has sampling error SE = .06. a. Assume that p is near .3. b. Assume that you have no prior...

Bangkok Instruments, Ltd. Balance Sheet, March 1, thousands of Thai bahts Exchange rates for translating Bangkok Instrument's balance sheet into U.S. dollars are: 11.9 Bangkok Instruments, Ltd. (B)....

1. Calculate the beta for the stock . Using Excel and the DATA worksheet, calculate the stock's beta by regressing the monthly stock returns on the market's monthly returns. 2. Re-calculate the beta...

In Melanie's Styling Salon, the time to complete a simple haircut is normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes. What percent of customers require less than...