6.2

a pizza parlor: mean= 8 ounces standard deviaiton= 0.5 ounces picks out a large pizza at random, finds made up of 6.9 ounces of cheese; amount of cheese on pizza is a normal distribution how many standard deviations from the mean is 6.9?

-2.20 meaning, the amont of cheese is 2.20 standard devioations below the mean

fawn weighs 14 kg, is it an unusually small animal? mean= 27.4 standard deiation= 3.4 kg

...

let z be a random variable with a standard normal distribution. find the indicated probability. P(z less than or equal to -0.29)

.3859

mean of original distribution in standard units is

0

what is the value of the standard score for the mean of a distribution

0

the z distribution, in a normal distribution has a mean of .... and a standard deviation of ....

0 1

let z be a random variable with a standard normal distribution. find the probability. P(Z greater than or equal to 1.96)

0.0250

find indicated probability: P(-0.40 <|z|> 2.08

0.6366

2 conventions for the table

1. any area to the left of z value smaller than -3.49 as 0 2. treat any area to the right of z value greater than 3.49 as 1.000

Rod: mean: 17 minutes standard deviation= 3 minutes -took him 21 minutes to get to class; how many standard deviations from the average? -what commuting time corresponds to standard score of z=-2.5?

1.33 9.5 minutes

any normal distribution can be converted to the standard normal distribution

by converting all x values to their corresponding z values

if the original distribution of x values is normal, then the

corresponding z values have a normal distribution as well

how these types of questions will be formualted- ones with z values whose probabilities need to be taken from the table

let z be a random variable with a standard normal distribution

what are the values of the mean and standard deviation of a standard normal distribution?

mean= 0 standard deviation= 1

each area is equal to the

probability that the measurement of that item falls in this interval

what about a raw score greate rthan a mean? in relation to standard scores

raw scores above the mean will have positive standard scores

does a raw score less than the mean equal positive or negative standard score?

raw scores less than the mean will have negative standard scores

z value gives the number of

standard deviations between the original x and the mean of the x distribution

the z values on the ________ _____ ______ have _____ beyond for their value

standard normal distribution; area

what can help find the area under the standard normal curve?

the standard normal distribution

given an .... distribution with a mean and standard deviation, what can one find?

x; raw score x corresponding to a z score

if a z value is negative, is the area to the left of z less than 0.5?

yes

if a z value is positive, is the area to the left of z greater than 0.5?

yes

as z values increase, do areas to the left of z increase?

yes,

x value below the mean has

a negative z value

the standard normal distribution is

a normal distribution with mean 0 and standard deviation 1

an x value in the original distribution above the mean has

a z value that is positive