HP 33s Scientific manual 16-16Statistics Programs, Value

XD	%@
	value
3 g	/
	)

10000 z )

Starts the distribution program and prompts for X.

Enters 3 for X and starts computation of Q(X). Displays the ratio of the population smarter than everyone within three standard deviations of the mean.

Multiplies by the population. Displays the approximate number of blind dates in the local population that meet the criteria.

Since your friend has been known to exaggerate from time to time, you decide to see how rare a "2σ" date might be. Note that the program may be rerun simply by pressing g.

Keys:	Display:	Description:
(In RPN mode)

g%@

)

2 g	/
	)
10000 z	 )

Resumes program.

Enters X–value of 2 and calculates Q(X).

Multiplies by the population for the revised estimate.

Example 2:

The mean of a set of test scores is 55. The standard deviation is 15.3. Assuming that the standard normal curve adequately models the distribution, what is the probability that a randomly selected student scored at least 90? What is the score that only 10 percent of the students would be expected to have surpassed? What would be the score that only 20 percent of the students would have failed to achieve?

Keys:	Display:	Description:
(In RPN mode)
XS	@	Starts the initialization routine.
	)

16–16Statistics Programs