A random sample of size n = 225 is taken from a population with population proportion P = 0.81. Use Table 1
a. Calculate the expected value and the standard error for the sampling distribution of the sample proportion. (Round "expected value" to 2 decimal places and "standard error" to 4 decimal places.)
Expected value Standard error
b. What is the probability that the sample proportion is between 0.80 and 0.90? (Round "z" value to 2 decimal places, and final answer to 4 decimal places.)
Probability
c. What is the probability that the sample proportion is less than 0.80? (Round "z" value to 2 decimal places, and final answer to 4 decimal places.)
Probability