High School

We appreciate your visit to A junior football league has players whose weights are normally distributed with a mean weight of 182 lbs and a standard deviation of 9 5. This page offers clear insights and highlights the essential aspects of the topic. Our goal is to provide a helpful and engaging learning experience. Explore the content and find the answers you need!

A junior football league has players whose weights are normally distributed with a mean weight of 182 lbs and a standard deviation of 9.5 lbs. If 25 players are selected at random, what is the probability that their mean weight would be less than 180 lbs?

Answer :

To find the probability that the mean weight of 25 randomly selected players is between 180 lbs, we can use the properties of the normal distribution.

First, we identify the known values:

  • Mean of the population, [tex]\mu = 182[/tex] lbs
  • Standard deviation of the population, [tex]\sigma = 9.5[/tex] lbs
  • Sample size, [tex]n = 25[/tex]

The mean of the sample distribution will also be [tex]\mu = 182[/tex] lbs. However, the standard deviation of the sample mean (known as the standard error) is calculated as:

[tex]\text{Standard Error} = \frac{\sigma}{\sqrt{n}} = \frac{9.5}{\sqrt{25}} = \frac{9.5}{5} = 1.9[/tex]

Now, we need to standardize the sample mean to use the standard normal distribution (Z-distribution). The formula for a Z-score is:

[tex]Z = \frac{\bar{X} - \mu}{\text{Standard Error}}[/tex]

We want to find the probability that the sample mean is less than 180 lbs:

  • For 180 lbs:
    [tex]Z_{180} = \frac{180 - 182}{1.9} = \frac{-2}{1.9} \approx -1.053[/tex]

Next, we find the probability associated with [tex]Z = -1.053[/tex]. Using the standard normal distribution table or a calculator, we find:

[tex]P(Z < -1.053) \approx 0.1469[/tex]

Therefore, the probability that the mean weight of the selected players is less than 180 lbs is approximately 0.1469, or 14.69%.

Thanks for taking the time to read A junior football league has players whose weights are normally distributed with a mean weight of 182 lbs and a standard deviation of 9 5. We hope the insights shared have been valuable and enhanced your understanding of the topic. Don�t hesitate to browse our website for more informative and engaging content!

Rewritten by : Barada