Software companies work hard to produce software without bugs. A particular company claims that 85% of the software it produces is bug free. A random sample of size 200 showed 156 softwareprograms were bug free.
a. Calculate the mean of the sampling distribution of the sample proportion.
b. Calculate the standard deviation of the sampling distribution of the sample proportion. (Round your answer to four decimal places.)
c. The shape of the sampling distribution of the sample proportion is approximately normal. Which of the following choices justifies that statement? ( MULTIPLE CHOICE)
A.The sample size is greater than 30.
B.We have sampled less than 10% of the population.
C.np ≥ 10 and n(1 − p) ≥ 10
D.A random sample was taken.
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D. Calculate the probability of obtaining a sample result of 156 out of 200 or less if the company's claim is true. (Use a table or technology. Round your answer to four decimal places.)
