the conservative sample size required to estimate a population proportion pi to within .05 with 95% confidence

Question

a. 385
b. 1537
c. 40
d.10

Answer 1

The margin of error is 1.96 * sqrt(pq/n). In this case, we take p = q = 0.5. Thus we have:
1.96 sqrt(0.25/n) <= 0.05
Solving that gives n >= 384.16, so a).

Answer 2

pattern length = (z* std dev/margin of blunders)^2 Use the arrogance point to locate z-score. to locate ninety% self assurance, its a million - 0.9 =.10 .10/2 =.05 a million minus the .05 = .ninety 5=the z-percentile to examine on z-chart. So we've been finding for cumulative danger; z –percentile of .ninety 5 on z-chart this is a z-score of a million.645. that's a handy self assurance era chart the place % optimistic corrosponds to z-score. 70% a million.04 seventy 5% a million.15 80% a million.28 80 5% a million.40 4 ninety% a million.645 ninety two% a million.seventy 5 ninety 5% a million.ninety six ninety six% 2.05 ninety 8% 2.33 ninety 9% 2.fifty 8 one hundred% 2.80 one verify the pattern length required to estimate a inhabitants recommend to interior of 11 instruments on condition that the inhabitants time-honored deviation is 50. A self assurance point of ninety% is judged to be suitable. N =(a million.645 *50/11)^2=fifty 5.91=fifty six 2. verify the pattern length required to estimate a inhabitants recommend to interior of 11 instruments on condition that the inhabitants time-honored deviation is a hundred and fifteen. Use a self assurance point of ninety%. pattern length = (a million.645 * 10.455)^2 = 293.ninety six =294 3. verify the pattern length required to estimate a inhabitants recommend to interior of 11 instruments on condition that the inhabitants time-honored deviation is 50. Use a self assurance point of ninety 5%. pattern length = (a million.960 * 4.545)^2 = seventy 9.37= 80 4. verify the pattern length required to estimate a inhabitants recommend to interior of 20 instruments on condition that the inhabitants time-honored deviation is 50. A self assurance point of ninety% is judged to be suitable pattern length =(a million.645 * 2.5)^2= sixteen.8 =17