Texas Instruments TI-83 Plus Manual page 47

nd
Press the 2 key and then press the VARS key to get
to the DISTR page.
Press the number 2 key.
Type in -1E99, 31.8, 32, .3/ 20 ))
Press the ENTER key.
The probability is .0014.
Example: Tuition
According to a recent College report, the average tuition and fees at four year private colleges
and universities in the United States is $18,273 for the academic year 2002–2003. Suppose that
the tuition's exact distribution is unknown but its mean is $18,273 and its standard deviation is
$2100. If 49 four-year colleges and universities are chosen at random. What is the probability
that the average tuition of the 49 schools is greater than $19,000.
nd
Press the 2 key and then press the VARS key to get
to the DISTR page.
Press the number 2 key.
Type in 19000, 1E99, 18273, 2100/ 49 ))
Press the ENTER key.
The probability is .0077.
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