/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q 21. The birthday problem What鈥檚 th... [FREE SOLUTION] | 91影视

91影视

The birthday problem What鈥檚 the probability that in a randomly selected group of30 unrelated people, at least two have the same birthday? Let鈥檚 make two

assumptions to simplify the problem. First, we鈥檒l ignore the possibility of a February 29 birthday. Second, we assume that a randomly chosen person is equally likely to be born on each of the remaining 365 days of the year.

(a) How would you use random digits to imitate one repetition of the process? What variable would you measure?

(b) Use technology to perform 5 repetitions. Record the outcome of each repetition.

(c) Would you be surprised to learn that the theoretical probability is 0.71? Why or why not?

Short Answer

Expert verified

Part (a) The number of times a number appears is counted.

Part (b) The number of times a number appears in a row is counted.

Part (c) It is not surprising.

Step by step solution

01

Part (a) Step 1. Given Information   

n=30 persons were chosen at random. Assume that a randomly picked person is equally likely to be born on each of the other 365 days of the year, ignoring the probability of a February 29 birthday.

02

Part (a) Step 2. Concept Used 

We can't foresee the outcomes of a chance process, yet they have a regular distribution over a large number of repetitions. According to the law of large numbers, the fraction of times a specific event occurs in numerous repetitions approaches a single number. The likelihood of a chance outcome is its long-run relative frequency. A probability is a number between 0 (never happens) and 1 (happens frequently) (always occurs).

03

Part (a) Step 3. Explanation     

To simulate one repetition of the procedure, use random digits as follows: Use numbers with three digits. It corresponds to a birthday if the numbers are between 000 and 364 If the number is in the range of 365 to 999 it should be ignored. Randomly select numbers between 000 and 364 Then count how many times each number appears in the 30-number list. The number of times a number appears is counted.

04

Part (b) Step 1. Explanation  

Use numbers with three digits. It corresponds to a birthday if the numbers are between 000and 364If the number is in the range of 364 to 999, it should be ignored. Randomly select numbers between 000 and 999 For one simulation, execute the following command on your Ti83/Ti84 calculator: randlnt(0,364,30), where the command randlnt is found under PRB in the MATH-menu. Five trips through the simulation. Determine the number of times each simulation is repeated.

05

Part (c) Step 1. Explanation   

The theoretical probability of 0.71 is not surprising, given that (almost) all simulations had repeated birthdays in exercise (b). As a result, it's not surprising.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Due to a hit, A very good professional baseball player gets a hit about 35% of the time over an entire season. After the player failed to hit safely in six straight at-bats, a TV commentator said, 鈥淗e is due for a hit by the law of averages.鈥 Is that right? Why?

Lotto In the United Kingdom鈥檚 Lotto game, a player picks six numbers from 1 to 49 for each ticket. Rosemary bought one ticket for herself and one for each of her four adult children. She had the lottery computer randomly select the six numbers on each ticket. When the six winning numbers were drawn, Rosemary was surprised to find that none of these numbers appeared on any of the five Lotto tickets she had bought. Should she be? Design and carry

out a simulation to answer this question. Follow the four-step process.

Taking the train According to New Jersey Transit, the 8:00 a.m. weekday train from Princeton to New York City has a 90% chance of arriving on time. To test this claim, an auditor chooses 6 weekdays at random during a month to ride this train. The train arrives late on 2 of those days. Does the auditor have convincing evidence that the company鈥檚 claim isn鈥檛 true? Design and carry out a simulation to answer this question. Follow the four-step process.

Tall people and basketball players Select an adult at random. Define events T: a person is over 6 feet tall, and B: a person is a professional basketball player. Rank the following probabilities from smallest to largest. Justify your answer.

P(T)P(B)P(T|B)P(B|T)

Fill 鈥檈rr up! In a recent month, 88%of automobile drivers filled their vehicles with regular gasoline, 2%purchased midgrade gas, and 10%bought premium gas.17 Of those who bought regular gas, 28% paid with a credit card; of customers who bought midgrade and premium gas, 34% and 42%, respectively, paid with a credit card. Suppose we select a customer at random.

Draw a tree diagram to represent this situation. What鈥檚 the probability that the customer paid with a credit card? Use the four-step process to guide your work.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.