Welcome to Westonci.ca, where curiosity meets expertise. Ask any question and receive fast, accurate answers from our knowledgeable community. Discover comprehensive answers to your questions from knowledgeable professionals on our user-friendly platform. Connect with a community of professionals ready to help you find accurate solutions to your questions quickly and efficiently.

Becky and Carla take an advanced yoga class. Becky can hold 29% of her poses for over a minute, while Carla can hold 35% of her poses for over a minute. Suppose each yoga student is asked to hold 50 poses. Let B = the proportion of poses Becky can hold for over a minute and C = the proportion of poses Carla can hold for over a minute. What is the probability that Becky’s proportion of poses held for over a minute is greater than Carla’s?

Sagot :

Using the normal distribution and the central limit theorem, it is found that there is a 0.2033 = 20.33% probability that Becky’s proportion of poses held for over a minute is greater than Carla’s.

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.
  • By the Central Limit Theorem, for a proportion p in a sample of size n, the sampling distribution of sample proportion is approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1 - p)}{n}}[/tex], as long as [tex]np \geq 10[/tex] and [tex]n(1 - p) \geq 10[/tex].

For each sample, we have that:

[tex]p_B = 0.29, s_B = \sqrt{\frac{0.29(0.71)}{50}} = 0.046[/tex]

[tex]p_C = 0.35, s_C = \sqrt{\frac{0.35(0.65)}{50}} = 0.057[/tex]

For the distribution of the difference of the proportions of Becky and Carla, we have that:

[tex]\mu = p_B - p_C = 0.29 - 0.35 = 0.06[/tex]

[tex]s = \sqrt{s_B^2 + s_C^2} = \sqrt{0.046^2 + 0.057^2} = 0.073[/tex]

The probability that Becky’s proportion of poses held for over a minute is greater than Carla’s is the probability that the subtraction is above 0, that is, 1 subtracted by the p-value of Z when X = 0, hence:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{0 + 0.06}{0.073}[/tex]

[tex]Z = 0.82[/tex]

[tex]Z = 0.82[/tex] has a p-value of 0.7967.

1 - 0.7967 = 0.2033.

0.2033 = 20.33% probability that Becky’s proportion of poses held for over a minute is greater than Carla’s.

To learn more about the normal distribution and the central limit theorem, you can check https://brainly.com/question/24663213