Question

In: Statistics and Probability

Assume that 85% of STAT 207 students pass the course. If a random sample of 160...

Assume that 85% of STAT 207 students pass the course. If a random sample of 160 STAT 207 students is taken, find the probability that at least 130 of them pass the course?

Solutions

Expert Solution

P[ STAT 207 students pass the course ] = 85% = 0.85

Number of students = 160

Proportion = 130/160 = 0.8125

The following information has been provided about the population proportion and the sample size:

Population Proportion = 0.85
Sample Size = 160

We need to compute . Based on the information provided, the population men of sample proportions and the corresponding standard error are:

Observe that:

which indicates that the assumption for normal approximation for the sampling distribution is met.

Now, the following is obtained using normal approximation:

= 0.908  

P[ umber of students passing more than 130 ] = 0.908

orchestra answered 3 years ago
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