Consider the probability that greater than 100 out of 151 students will pass their college placement exams. Assume the probability that a given student will pass their college placement exam is 64%. Approximate the probability using the normal distribution. Round your answer to four decimal places.

Respuesta :

Answer:

0.3137 is the probability that more than 100 students will pass the college placement exam.    

Step-by-step explanation:

We are given the following in  the question:

Sample size, n = 151

probability student will pass their college placement exam = 64%

[tex]p = 0.64[/tex]

Formula:

[tex]\mu = np = 151(0.64) = 96.64\\\sigma = \sqrt{np(1-p)} = \sqrt{151(0.64)(1-0.64)} = 5.89[/tex]

We have to evaluate

P(x > 100)

Formula:

[tex]z_{score} = \displaystyle\frac{x-\mu}{\sigma}[/tex]

[tex]P( x > 100) = P(100-0.5) = P( z > \displaystyle\frac{99.5 - 96.64}{5.89})\\\\ = P(z > 0.4855)[/tex]

[tex]= 1 - P(z \leq 0.4855)[/tex]

Calculation the value from standard normal z table, we have,  

[tex]P(x >99.5) = 1 - 0.6863 =0.3137 = 31.37\%[/tex]

0.3137 is the probability that more than 100 students will pass the college placement exam.