Skip to main content
Ch. 5 - Discrete Probability Distributions
Triola - Elementary Statistics 14th Edition
Triola14th EditionElementary StatisticsISBN: 9780137366446Non è quello che usi tu?Cambia libro di testo
Capitolo 5, Problema 5a

 In Exercises 5–8, assume that the Poisson distribution applies; assume that the mean number of Atlantic hurricanes in the United States is 5.5 per year, as in Example 1; and proceed to find the indicated probability.


Hurricanes


a. Find the probability that in a year, there will be 7 hurricanes.

Guida verificata passo dopo passo
1
Step 1: Understand the Poisson distribution. The Poisson distribution is used to model the probability of a given number of events occurring in a fixed interval of time or space, given a known average rate of occurrence (mean). The formula for the Poisson probability is P(X = k) = (λ^k * e^(-λ)) / k!, where λ is the mean number of occurrences, k is the number of occurrences, and e is the mathematical constant approximately equal to 2.718.
Step 2: Identify the given values. From the problem, the mean number of hurricanes per year (λ) is 5.5, and we are tasked with finding the probability of exactly 7 hurricanes (k = 7).
Step 3: Substitute the values into the Poisson formula. Replace λ with 5.5 and k with 7 in the formula: P(X = 7) = (5.5^7 * e^(-5.5)) / 7!.
Step 4: Break down the calculation. Compute each component step-by-step: (1) Calculate 5.5^7, (2) Compute e^(-5.5), (3) Find the factorial of 7 (7!), and (4) Divide the product of 5.5^7 and e^(-5.5) by 7!.
Step 5: Interpret the result. Once the probability is calculated, it represents the likelihood of observing exactly 7 hurricanes in a year under the given conditions. This value can be compared to other probabilities to understand the distribution of hurricane occurrences.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
1m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Poisson Distribution

The Poisson distribution is a probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time or space, given a known average rate of occurrence. It is particularly useful for modeling rare events, such as natural disasters, where the events occur independently. The formula for the Poisson probability mass function is P(X=k) = (λ^k * e^(-λ)) / k!, where λ is the average rate, k is the number of occurrences, and e is Euler's number.
Video consigliato:
Percorso guidato
06:38
Intro to Frequency Distributions

Mean (λ)

In the context of the Poisson distribution, the mean (denoted as λ) represents the average number of occurrences of the event in a specified interval. For this question, λ is given as 5.5, indicating that, on average, there are 5.5 hurricanes per year in the United States. This parameter is crucial for calculating the probabilities of different outcomes using the Poisson formula.
Video consigliato:
Percorso guidato
04:52
Calculating the Mean

Probability Calculation

To find the probability of a specific number of events occurring in a Poisson distribution, one uses the Poisson probability mass function. For this question, to find the probability of exactly 7 hurricanes in a year, you would substitute k=7 and λ=5.5 into the formula. This calculation will yield the likelihood of observing that exact number of hurricanes, which is essential for understanding the variability and risk associated with hurricane occurrences.
Video consigliato:
Percorso guidato
07:09
Probability From Given Z-Scores - TI-84 (CE) Calculator
Pratica correlata
Domanda del libro di testo

Using Probabilities for Significant Events


a. Find the probability of getting exactly 1 match.

200
views
Domanda del libro di testo

In Exercises 31 and 32, assume that hybridization experiments are conducted with peas having the property that for offspring, there is a 0.75 probability that a pea has green pods (as in one of Mendel’s famous experiments).


Hybrids Assume that offspring peas are randomly selected in groups of 16.


a. Find the mean and standard deviation for the numbers of peas with green pods in the groups of 16.

153
views
Domanda del libro di testo

Lottery. In Exercises 15–20, refer to the accompanying table, which describes probabilities for the California Daily 4 lottery. The player selects four digits with repetition allowed, and the random variable x is the number of digits that match those in the same order that they are drawn (for a “straight” bet).


Using Probabilities for Significant Events


a. Find the probability of getting exactly 2 matches.

113
views
Domanda del libro di testo

In Exercises 5–8, assume that the Poisson distribution applies; assume that the mean number of Atlantic hurricanes in the United States is 5.5 per year, as in Example 1; and proceed to find the indicated probability.

b. In a 118-year period, how many years are expected to have no hurricanes?

126
views
Domanda del libro di testo

In Exercises 31 and 32, assume that hybridization experiments are conducted with peas having the property that for offspring, there is a 0.75 probability that a pea has green pods (as in one of Mendel’s famous experiments).


Hybrids Assume that offspring peas are randomly selected in groups of 16.


b. Use the range rule of thumb to find the values separating results that are significantly low or significantly high.

198
views
Domanda del libro di testo

One of Mendel’s famous experiments with peas resulted in 580 offspring, and 152 of them were yellow peas. Mendel claimed that under the same conditions, 25% of offspring peas would be yellow. Assume that Mendel’s claim of 25% is true, and assume that a sample consists of 580 offspring peas.


b. Find the probability of exactly 152 yellow peas.


111
views