AP Stats Chap. 2

What is z-score

how many standard deviations something is away from the mean

What changes when you add 10 to the data set

mean, median, Q1, Q3, min, max

What stays the same when you add 10 to the data set

spread (S.D., IQR, Range)

What is the lower limit formula

Q1 - 1.5 (IQR)

What is the upper limit formula

Q3 + 1.5 (IQR)

2 standard deviations from the mean

95%

1 standard deviation from the mean

68%

3 standard deviations from the mean

99.7%

how to calculate z-score

(data value - mean) / standard deviation

IQR formula

Q3-Q1

What to enter into InvNorm

area: z score

Whichever side of the graph the date point is on

What to enter into Normal cdf

If percentage is below 50:

lower: percentage as decimal

upper: 1e99

If percentage is higher than 50

lower: -1e99

upper: percentage as decimal