SOLUTION: n a study of government financial aid for college students, researchers needed to estimate the proportion of full-time college students who earn a bachelor's degree in 4 years or l

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Question 1192657: n a study of government financial aid for college students, researchers needed to estimate the proportion of full-time college students who earn a bachelor's degree in 4 years or less. Assuming a confidence level of 90%, find the sample size needed to estimate that proportion with a 0.03 margin of error in two cases: (1) no assumptions are made about the value of the sample proportion, and (2) prior studies have shown that roughly 60% of full-time students earn a bachelor's degree in four years or less. (Round your answers upward to the next higher integer.)
Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
error=z(0.95)*std error
0.03=1.645*sqrt(0.5*0.5/n)
square both sides
0.0009=2.706*0.25/n
multiply both sides by n and divide both by 0.0009
n=2.706*0.25/0.0009
=751.67=752
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0.03=1.645*sqrt(0.6*0.4/n)
n=2.706*0.24/0.0009
=721.6 or 722