AP Stat Confidence interval practice

Confidence intervals

100

You want to estimate the proportion of students who take an AP class. You get a 90% confidence interval of (.26, .38). Interpret this interval

We are 90% confident that the interval from .26 to .38 captures the true proportion of students who take an AP class

150

You take a survey and find 18 out of 90 students take an AP class. Find the 80% confidence interval for this data.

(.14597, .25403)

Confidence Intervals 2

100

What is the critical value that goes with a confidence level of 99%? (when you're using Z)

2.58

150

Name two ways to WIDEN a confidence interval

Decrease sample size

Increase confidence level

Violating CI rules

100

You want to know about the average height of all the students at Berks Catholic and to do this you measure the heights of 100 seniors. Based on this data you set up a confidence interval.

Not a random sample

150

You want to know about the proportion of students who are an only child. You ask a random sample of 50 students and 48 say yes they are, and 2 say they are not

We don't have at least 10 yes and at least 10 no

On this day in history

100

April 4 2011 UConn defeated Butler in the national championship while being lead by this star point guard who would later be drafted in the top 10

Who is Kemba Walker?

150

April 4 2005, Illinois lost the national championship to UNC. Illinois was lead by this star point guard who was later a top 3 draft pick for the Utah Jazz. He played there for years before being traded to the Nets

Who is Deron Williams?

175

One rapper had the #1 song on April 4th in both 2003 and 2005. Name the artist based on this instrumental from the 2003 song

50 Cent 

Misc (at least 3 questions must have been answered already before you pick this)

100

Who did this?

Two people who (allegedly) let their friend take the fall with them