/*! 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 4 Find the indicated probability u... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Find the indicated probability using the geometric distribution. $$ \text { Find } P(8) \text { when } p=0.28 \text {. } $$

Short Answer

Expert verified
The probability that the first success occurs on the 8th trial is approximately 0.0390.

Step by step solution

01

Understand the Question

The problem asks us to find the probability that the first success occurs on the 8th trial in a geometric distribution where the probability of success on each trial is given as \( p = 0.28 \).
02

Formula for Geometric Distribution

The probability that the first success occurs on the \( n \)-th trial in a geometric distribution is given by the formula: \( P(n) = (1-p)^{n-1} \cdot p \). For this problem, \( n = 8 \) and \( p = 0.28 \).
03

Substitute Values

Substitute \( p = 0.28 \) and \( n = 8 \) into the formula: \( P(8) = (1-0.28)^{8-1} \cdot 0.28 \).
04

Calculate \( (1-p)^{n-1} \)

Calculate \((1-0.28)^{7} = 0.72^{7}\). Using a calculator, \(0.72^{7} \approx 0.1394\).
05

Complete the Probability Calculation

Multiply the result by \( p \): \( 0.1394 \times 0.28 = 0.0390 \). This is the probability that the first success occurs on the 8th trial.

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.

Probability Calculation
Probability calculation is a fundamental concept in statistics, especially for distributions like the geometric distribution. The process of calculating probability involves determining the likelihood of a particular event happening. In the context of the geometric distribution, this means finding out how probable it is for the first successful outcome of an experiment to occur on a specific trial.

To accomplish this calculation, you follow specified steps that often begin with using a probability formula. Understanding each step ensures you accurately determine probabilities for different scenarios.
  • Identify the parameters: Here, you'd define the number of trials (e.g., the 8th trial).
  • Find the initial settings: This includes determining the success rate of each attempt (e.g., 0.28).
  • Utilize the formula: Substitute the parameters into the geometric probability formula, which involves more than just arithmetic but also understanding the sequence logic.
These calculations contribute significantly to areas where predicting when the first success will occur is essential, such as in quality testing or certain industrial processes.
First Success
In the context of a geometric distribution, the concept of the "first success" is pivotal. This term refers to the first occurrence of a successful result in a series of independent trials. For instance, if you are rolling a die and looking for the first time a specific number appears, the trial on which this occurs is referred to as the first success.

The geometric distribution is particularly useful in predicting scenarios involving repetitive trials where each trial is independent of the others. A crucial aspect of understanding the first success is recognizing that:

  • Each trial is independent, meaning previous outcomes do not influence future results.
  • There is a constant probability of success across all trials.
  • The aim is to find when the first occurrence happens, not how many times it occurs.
Appreciating this concept is essential if you're solving probability problems related to the geometric distribution. It's often used in real-world scenarios like customer service, where you might predict when a first satisfied customer interaction will occur.
Probability Formula
To solve problems involving geometric distribution, mastering the probability formula is critical. This formula calculates the likelihood that the first success occurs on a specific trial. The formula itself is:
\[ P(n) = (1-p)^{n-1} \cdot p \]Here, \( P(n) \) indicates the probability of the first success happening on the \( n \)-th trial. Understanding each component of this formula is crucial:
  • \( p \): Probability of success on any given trial.
  • \( (1-p)^{n-1} \): Represents the probability of failure up to the trial before the first success. For example, failing in the first 7 trials if success is expected on the 8th.
This formula is straightforward to apply once you understand its components, making it a handy tool for many statistical predictions related to time or trial-based processes.

Using this formula correctly enables you to solve various probability-related tasks with confidence, turning abstract concepts into actionable predictions.

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

Find the indicated probability using the geometric distribution. $$ \text { Find } P(5) \text { when } p=0.09 \text {. } $$

Hypergeometric Distribution Binomial experiments require that any sampling be done with replacement because each trial must be independent of the others. The hypergeometric distribution also has two outcomes: success and failure. The sampling, however, is done without replacement. For a population of \(N\) items having \(k\) successes and \(N-k\) failures, the probability of selecting a sample of size \(n\) that has \(x\) successes and \(n-x\) failures is given by $$ P(x)=\frac{\left({ }_{k} C_{x}\right)\left({ }_{N-k} C_{n-x}\right)}{{ }_{N} C_{n}} $$ In a shipment of 15 microchips, 2 are defective and 13 are not defective. \(\mathrm{A}\) sample of three microchips is chosen at random. Use the above formula to find the probability that (a) all three microchips are not defective, (b) one microchip is defective and two are not defective, and (c) two microchips are defective and one is not defective.

Use the fact that the mean of a geometric distribution is \(\mu=1 / p\) and the variance is \(\sigma^{2}=q / p^{2}\). Daily Lottery A daily number lottery chooses three balls numbered 0 to \(9 .\) The probability of winning the lottery is \(1 / 1000\). Let \(x\) be the number of times you play the lottery before winning the first time. (a) Find the mean, variance, and standard deviation. (b) How many times would you expect to have to play the lottery before winning? (c) The price to play is \(\$ 1\) and winners are paid \(\$ 500\). Would you expect to make or lose money playing this lottery? Explain.

Find the indicated probability using the Poisson distribution. $$ \text { Find } P(2) \text { when } \mu=1.5 \text {. } $$

Use the fact that the variance of the Poisson distribution is \(\sigma^{2}=\mu\). Bankruptcies The mean number of bankruptcies filed per hour by businesses in the United States in 2016 was about 2.8. (a) Find the variance and the standard deviation. Interpret the results. (b) Find the probability that at most five businesses will file bankruptcy in any given hour. (Source: Administrative Office of the U.S. Courts)

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.