# AP Statistics 3.2 Statistical Inference

AP Statistics 3.2 Statistical Inference. What was the confidence level that the statistician used in the interval?

 AP AP Statistics AP Statistics Statistical Inference Language English Language Test Prep AP Statistics

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00:29

mean number of donuts bought was 3.84 with a standard deviation of 1.12 and

00:34

the confidence interval he received was 3.6205 by 4.0595. What

00:40

was the confidence level that the statistician used in the interval? All

00:43

right here the potential answers....Well if you calculate using the lower limit of

00:50

3.6 205 the mean of 3.84 and 1.12 is the standard deviation while your formula [maths formula on a piece of paper]

00:57

looks like this the Z value equals 1.96 so where does that equate in the Z table

01:03

at the ninety percent confidence level no. Not at the 97 98 or 99 percent levels [Teacher pointing to confidence levels]

01:10

either that leaves B; It's a 95 percent confidence level and yeah that's

01:14

the correct answer once again proving that knowing your Z table like the back

01:18

of your hand is your avenue to success with stats. Hopefully this donut problem [Man holding hand up with Z table on his palm and kid eating a doughnut]

01:22

made sense to you and you're not sitting there with a glazed look in your eyes..