1) A poll is conducted to determine the percentage of adults who own an iPhone. In this poll, \(500\) people were surveyed and \(63\%\) stated they own an iPhone. What is the margin of error associated with \(95\%\) confidence?
2) A survey of \(800\) students was conducted to determined the percentage of students who were in favor of a new late start schedule. The results showed \(74\%\) of students preferred the change. What is the margin of error for \(95\%\) confidence?
3) Using the same survey results from #2, determine the margin of error for \(98\%\) confidence.
4) Explain the relationship between the answers in #2 and #3. Which is greater? Why does it make sense for one to be greater?
5) A survey of \(250\) people reported a margin of error of \(\pm 4% \). What was the level of confidence for the poll?
6) Suppose a pollster wants a margin of error of no more than \(3\%\) with \(98\%\) confidence. How many people should he poll?
7) A survey was taken of \(1200\) random households and found that \(72\%\) of them own more than one vehicle. Find the \(95\%\) confidence interval of the true proportion of households who own more than one vehicle.
Review
8) Find the intersection of the functions \(f(x)= \sin x\) and \(g(x)=(x-\frac{\pi}{2})^2 +1\). You can graph this to check, but you should be able to find the intersection just by thinking about the functions.
9) A poll is conducted by classifying Naperville by neighborhoods and then interviewing \(10\) random households in each neighborhood. Which random sampling method is being applied?
10) An iPhone passcode is typically made up of \(4\) digits where the digits can be repeated. If you randomly guess the passcode for your friends phone what is the probability that you guess it correct the first time?
11) Hadley looks up at the top of a \(20\) foot tree. The angle of elevation from her eyes to the top of the tree is \(32 ^{\circ}\). If her eyes are \(4\) feet of the ground, how far away is she standing from the tree?
12) Evaluate by hand \(\tan ( \large\frac{5 \pi}{4})\).
Solution Bank
2) A survey of \(800\) students was conducted to determined the percentage of students who were in favor of a new late start schedule. The results showed \(74\%\) of students preferred the change. What is the margin of error for \(95\%\) confidence?
3) Using the same survey results from #2, determine the margin of error for \(98\%\) confidence.
4) Explain the relationship between the answers in #2 and #3. Which is greater? Why does it make sense for one to be greater?
5) A survey of \(250\) people reported a margin of error of \(\pm 4% \). What was the level of confidence for the poll?
6) Suppose a pollster wants a margin of error of no more than \(3\%\) with \(98\%\) confidence. How many people should he poll?
7) A survey was taken of \(1200\) random households and found that \(72\%\) of them own more than one vehicle. Find the \(95\%\) confidence interval of the true proportion of households who own more than one vehicle.
Review
8) Find the intersection of the functions \(f(x)= \sin x\) and \(g(x)=(x-\frac{\pi}{2})^2 +1\). You can graph this to check, but you should be able to find the intersection just by thinking about the functions.
9) A poll is conducted by classifying Naperville by neighborhoods and then interviewing \(10\) random households in each neighborhood. Which random sampling method is being applied?
10) An iPhone passcode is typically made up of \(4\) digits where the digits can be repeated. If you randomly guess the passcode for your friends phone what is the probability that you guess it correct the first time?
11) Hadley looks up at the top of a \(20\) foot tree. The angle of elevation from her eyes to the top of the tree is \(32 ^{\circ}\). If her eyes are \(4\) feet of the ground, how far away is she standing from the tree?
12) Evaluate by hand \(\tan ( \large\frac{5 \pi}{4})\).
Solution Bank