Get personalized answers to your unique questions on IDNLearn.com. Explore a wide array of topics and find reliable answers from our experienced community members.
Sagot :
Using the normal distribution, it is found that:
a) The cutoff time for the fastest 5% of athletes in the men's group is of 3448.58.
b) The cutoff time for the slowest 10% of athletes in the women's group is of 6298.72.
Normal Probability Distribution
In a normal distribution 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]
- It 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, which is the percentile of X.
Item a:
For men, we have that [tex]\mu = 4378, \sigma = 565[/tex].
The cutoff for the fastest 5% of the athletes is the 5th percentile, which is X when Z has a p-value of 0.05, that is, X when Z = -1.645.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.645 = \frac{X - 4378}{565}[/tex]
[tex]X - 4378 = -1.645(565)[/tex]
[tex]X = 3448.58[/tex]
The cutoff time for the fastest 5% of athletes in the men's group is of 3448.58.
Item b:
For women, we have that [tex]\mu = 5212, \sigma = 849[/tex].
The cutoff is the 90th percentile, which is X when Z = 1.28, hence:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]1.28 = \frac{X - 5212}{849}[/tex]
[tex]X - 5212 = 1.28(849)[/tex]
[tex]X = 6298.72[/tex]
The cutoff time for the slowest 10% of athletes in the women's group is of 6298.72.
More can be learned about the normal distribution at https://brainly.com/question/24663213
We value your participation in this forum. Keep exploring, asking questions, and sharing your insights with the community. Together, we can find the best solutions. Find clear answers at IDNLearn.com. Thanks for stopping by, and come back for more reliable solutions.