SOLUTION: A random sample of size n = 120 is taken from a population with a population proportion p = 0.61. [You may find it useful to reference the z table.] a. Calculate the expect

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Question 1162678: A random sample of size n = 120 is taken from a population with a population proportion p = 0.61. [You may find it useful to reference the z table.]

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.)

b. What is the probability that the sample proportion is between 0.60 and 0.70? (Round ā€œzā€ value to 2 decimal places, and final answer to 4 decimal places.)

c. What is the probability that the sample proportion is less than 0.60? (Round ā€œzā€ value to 2 decimal places, and final answer to 4 decimal places.)


Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
E(X)=0.61
SE is sqrt (0.61*0.39)/120=0.0445
z=(0.60-0.61)/0.0445 and (0.70-0.61)/0.0445 and that is z between -0.22 and 2.02 or probability of 0.5654
less than 0.60 is z <-0.22 or probability of 0.4129