Respuesta :
Answer:
The number of students to be sampled is [tex]n = 1789 [/tex]
Step-by-step explanation:
From the question we are told that
The margin of error is E = 0.03
Generally the proportion of students that receive financial aid is mathematically represented as
[tex]\^ p = \frac{118 }{200}[/tex]
=> [tex]\^ p = 0.59[/tex]
From the question we are told the confidence level is 99% , hence the level of significance is
[tex]\alpha = (100 - 95 ) \%[/tex]
=> [tex]\alpha = 0.05[/tex]
Generally from the normal distribution table the critical value of [tex]\frac{\alpha }{2}[/tex] is
[tex]Z_{\frac{\alpha }{2} } = 2.58 [/tex]
Generally the sample size is mathematically represented as
[tex]n = [\frac{Z_{\frac{\alpha }{2} }}{E} ]^2 * \^ p (1 - \^ p ) [/tex]
=> [tex]n = [\frac{2.58}{0.03} ]^2 * 0.59(1 - 0.59) [/tex]
=> [tex]n = 1789 [/tex]
Using the margin of error, it is found that 1033 students would need to be sampled.
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
- z is the z-score that has a p-value of [tex]\frac{1+\alpha}{2}[/tex].
The margin of error is of:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
The dean randomly selects 200 students and finds that 118 of them are receiving financial aid, hence, the estimate is:
[tex]\pi = \frac{118}{200} = 0.59[/tex]
99% confidence level
So [tex]\alpha = 0.99[/tex], z is the value of Z that has a p-value of [tex]\frac{1+0.99}{2} = 0.995[/tex], so [tex]z = 2.575[/tex].
The sample size needed is n when M = 0.03, hence:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.03 = 1.96\sqrt{\frac{0.59(0.41)}{n}}[/tex]
[tex]0.03\sqrt{n} = 1.96\sqrt{0.59(0.41)}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.59(0.41)}}{0.03}[/tex]
[tex]\sqrt{n}^2 = \left(\frac{1.96\sqrt{0.59(0.41)}}{0.03}\right)^2[/tex]
[tex]n = 1032.5[/tex]
Rounding up, it is found that 1033 students would need to be sampled.
A similar problem is given at https://brainly.com/question/25420216
