/*! 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. 88 88. Scrabble In the game of Scra... [FREE SOLUTION] | 91影视

91影视

88. Scrabble In the game of Scrabble, each player begins by drawing 7 tiles from a bag containing 100tiles. There are 42vowels, 56 consonants, and 2 blank tiles in the bag. Cait chooses her7 tiles and is surprised to discover that all of them are vowels. Can we use a binomial distribution to approximate this probability? Justify your answer

Short Answer

Expert verified

No binomial distribution, because the draws are not independent and the constant probability of success is not constant.

Step by step solution

01

Given information

There are 42vowels, 56consonants, and 2blank tiles in the bag. Cait chooses her 7 tiles.

02

Explanation

A random variable has a binomial distribution if:

  • In terms of variables, there are two possible outcomes.
  • Each draw must be self-contained.
  • There are a set number of elements.
  • Probability of success is always the same.

The reason for this is that after selecting a tile, it is not returned to the bag and so cannot be selected again. As a result, the chances of winning after each tie are not the same.

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

North Carolina State University posts the grade distributions for its courses online.3Students in Statistics 101in a recent semester received 26%A42%Bs,20%Cs,10%Ds,and2%Fs. Choose a Statistics 101student at random. The student鈥檚 grade on a four-point scale (with A=4) is a discrete random variable Xwith this probability distribution:

Sketch a graph of the probability distribution. Describe what you see .

The mean of Tis

(a)110

(b)140

(c)180

(d)195

(e)250

85. Aircraft engines Engineers define reliability as the probability that an item will perform its function under specific conditions for a specific period of time. A certain model of aircraft engine is designed so that each engine has probability 0.999 of performing properly for an hour of flight. Company engineers test an SRS of 350 engines of this model. Let X= the number that operate for an hour without failure.
(a) Explain whyX is a binomial random variable.

(b) Find the mean and standard deviation ofX. Interpret each value in context.
(c) Two engines failed the test. Are you convinced that this model of engine is less reliable than it鈥檚 supposed to be? Compute P(X348) and use the result to justify your answer.

To introduce her class to binomial distributions, Mrs. Desai gives a 10-item, multiple choice quiz. The catch is, students must simply guess an answer (A through E) for each question. Mrs. Desai uses her computer's random number generator to produce the answer key, so that each possible answer has an equal chance to be chosen. Patti is one of the students in this class. Let X=the number of Patti's correct guesses.

Find P(X=3). Explain what this result means.

A large auto dealership keeps track of sales made during each hour of the day. Let X= the number of cars sold during the 铿乺st hour of business on a randomly selected Friday. Based on previous records, the probability distribution of Xis as follows:

The random variable Xhas mean X=1.1and standard deviation X=0.943.

Suppose the dealership鈥檚 manager receives a 500bonus from the company for each car sold. Let Y = the bonus received from car sales during the 铿乺st hour on a randomly selected Friday. Find the mean and standard deviation of Y.

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.