/*! 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} Problem 22 Another die is weighted in such ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Another die is weighted in such a way that each of 1 and 2 is three times as likely to come up as each of the other numbers. Find the probability distribution. What is the probability of rolling an even number?

Short Answer

Expert verified
The probability distribution of the weighted die is: P(1) = P(2) = \(\frac{3}{10}\), and P(3) = P(4) = P(5) = P(6) = \(\frac{1}{10}\). The probability of rolling an even number on this weighted die is \(\frac{1}{2}\), or 50%.

Step by step solution

01

Calculate the probability of each number

Let's represent the probability of rolling 1 or 2 as \(3x\), and the probability of rolling any other number as \(x\). The total probability of all six numbers should be equal to 1. We have a total of six numbers on the die: two numbers with a probability of \(3x\) and four with a probability of \(x\), so the total probability is \(2(3x) + 4(x)\), which should be equal to 1. So, we have: \(2(3x) + 4(x) = 1\) Now, we will solve for \(x\). \(6x + 4x = 1\) \(10x = 1\) \(x = \frac{1}{10}\) Now that we know the value of \(x\), we can find the probabilities of each number. Probabilities: - Rolling a 1 or 2: \(3x = 3\left(\frac{1}{10}\right) = \frac{3}{10}\) - Rolling a 3, 4, 5, or 6: \(x = \frac{1}{10}\) The probability distribution of this weighted die is: - P(1) = P(2) = \(\frac{3}{10}\) - P(3) = P(4) = P(5) = P(6) = \(\frac{1}{10}\)
02

Find the probability of rolling an even number

Now, we will find the probability of rolling an even number (2, 4, or 6). To find the probability, we add up the probabilities of rolling a 2, 4, or 6: P(even) = P(2) + P(4) + P(6) = \(\frac{3}{10} + \frac{1}{10} + \frac{1}{10} = \frac{5}{10} = \frac{1}{2}\) So, the probability of rolling an even number on this weighted die is \(\frac{1}{2}\), or 50%.

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 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Weighted Die
A weighted die is different from a fair die because it's designed to land on certain numbers more frequently than others. In this case, the numbers 1 and 2 are more likely to appear than the other numbers on the die.

A regular six-sided die, often called a fair die, gives equal chances for each number to show up, meaning each number has a probability of \( rac{1}{6}\). However, with a weighted die, probabilities are not equal for all outcomes.

For this weighted die, 1 and 2 appear three times as often as the other numbers. This causes an imbalance in the likelihood of rolling certain numbers compared to a fair die, resulting in a probability distribution that reflects these differences.
Probability Calculation
Calculating probabilities involves understanding the likelihood of different outcomes occurring. To calculate the probability for this weighted die, we first represent the probability of rolling a 1 or 2 as \(3x\), while rolling any other number as \(x\).

Given there are two numbers with likelihood \(3x\) and four numbers with likelihood \(x\), all probabilities add up to 1 (because one of the six possible outcomes must occur). The equation is:
  • \(2(3x) + 4(x) = 1\)
  • Solving gives \(10x = 1\), and thus \(x = \frac{1}{10}\)
With this value, individual probabilities can be determined:
  • Probability of rolling 1 or 2: \(3x = \frac{3}{10}\)
  • Probability of rolling 3, 4, 5, or 6: \(x = \frac{1}{10}\)
This calculation results in a clear representation of what to expect when rolling the die.
Even Number Probability
An even number on a die is any number that can be divided evenly by 2, such as 2, 4, and 6. Understanding the probability of rolling such numbers helps determine how likely those specific outcomes are on a weighted die.

To find this probability, we sum the probabilities of rolling each even number. Here, we use the probabilities calculated previously:
  • Probability of rolling a 2: \(\frac{3}{10}\)
  • Probability of rolling a 4: \(\frac{1}{10}\)
  • Probability of rolling a 6: \(\frac{1}{10}\)
Adding these, the probability of rolling an even number becomes:\[P(2 \text{ or } 4 \text{ or } 6) = \frac{3}{10} + \frac{1}{10} + \frac{1}{10} = \frac{5}{10} = \frac{1}{2}\]This equates to a 50% chance, providing insight into how likely rolling an even number is on the weighted die.

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

\- Construct a four-state Markov system so that both \([.5 .500]\) and \(\left[\begin{array}{ll}0 & 0.5 .5\end{array}\right]\) are steady-state vectors. HINT [Try one in which no arrows link the first two states to the last two.]

Social Security According to the New York Times/CBS poll of March, 2005, referred to in Exercise \(65,49 \%\) agreed that Social Security taxes should be raised if necessary to keep the system afloat, and \(43 \%\) agreed that it would be a good idea to invest part of their Social Security taxes on their own. \({ }^{38} \mathrm{What}\) is the largest percentage of people who could have agreed with at least one of these statements? What is the smallest percentage of people who could have agreed with at least one of these statements?

Find a formula for the probability of the union of three (not necessarily mutually exclusive) events \(A, B\), and \(C\).

Social Security According to the New York Times/CBS poll of March, 2005, referred to in Exercise \(65,79 \%\) agreed that it should be the government's responsibility to provide a decent standard of living for the elderly, and \(43 \%\) agreed that it would be a good idea to invest part of their Social Security taxes on their own. \(^{37}\) What is the smallest percentage of people who could have agreed with both statements? What is the largest percentage of people who could have agreed with both statements?

A friend of yours asserted at lunch today that, according to the weather forecast for tomorrow, there is a \(52 \%\) chance of rain and a \(60 \%\) chance of snow. "But that's impossible!" you blurted out, "the percentages add up to more than \(100 \% . "\) Explain why you were wrong.

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.