IDNLearn.com is designed to help you find the answers you need quickly and easily. Discover prompt and accurate responses from our experts, ensuring you get the information you need quickly.
Sagot :
Answer:
0.0571 = 5.71% probability that this fund-raising event is a success
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The organizers would call this event a success if the total contributions exceed $4,600
Forty families, so sample mean above 4600/40 = 115.
Mean and a standard deviation of $105 and $40
This means that [tex]\mu = 105, \sigma = 40[/tex]
Sample of 40
This means that [tex]n = 40, s = \frac{40}{\sqrt{40}} = 6.3246[/tex]
What is the probability that this fund-raising event is a success?
Sample mean above 115, which is 1 subtracted by the pvalue of Z when X = 115. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{115 - 105}{6.3246}[/tex]
[tex]Z = 1.58[/tex]
[tex]Z = 1.58[/tex] has a pvalue of 0.9429
1 - 0.9429 = 0.0571
0.0571 = 5.71% probability that this fund-raising event is a success
We appreciate every question and answer you provide. Keep engaging and finding the best solutions. This community is the perfect place to learn and grow together. IDNLearn.com is committed to providing the best answers. Thank you for visiting, and see you next time for more solutions.