AP Statistics: Section 2.2 B
Recall finding a z-score in section 2.1: z =
We can use this formula to take any particular observation in a Normal distribution and convert it to a z-score. This new distribution of z-scores is called the ____________________________.
Its mean will be _____ and its standard deviation will be _____.
The notation for the standard Normal distribution is ______.
The standard Normal distribution is a density curve and thus the area under the curve must equal ____
Any question about the proportion of observations in a particular interval can be answered by finding the area under the curve.
Turn to Table A in the front of your text. Note that table A always gives the area to the left of the z-score.
Calculator: 2 nd VARS (DISTR) 2:normalcdf( ENTER normalcdf(lower limit, upper limit) normalcdf(1.32, 10000)
normalcdf(-.57, 1)
Normal Distribution Calculations We can answer any question about proportions of observations in a Normal distribution by ____________ and then using the Standard Normal table. standardizing
Calculator: normalcdf(240,10000, normalcdf(240, 10000, 170, 30)
Calculator: normalcdf(150,190,170,30)
Calculator: 2 nd VARS (DISTR) 3: invNorm( ENTER invNorm(area to left, invNorm(.25, 170, 30)
invNorm(.8, 170, 30)