Sharp EL-9900 operation manual 175

Chapter 10: Statistics & Regression Calculations

13 Zint2samp Finds the confidence bound of two sample means ∝1 and ∝2.

Example
Find the confidence interval of ∝			and ∝		of sample data with the
	_	1		2			= 3.4, n		_		=
confidence level of 0.9, where x			= 77.3, σ						= 30 and x
_	_ 1					1		1		2
75.2, σ2 = 2.8, n2 = 20 (x1 and x2 indicate sample means of two

data.)

Set the input method to value input mode

1.Press #SE17E.

2.Press SE13. Parameter input screen will appear.

3.Enter the appropriate value into each field.

4.Press @h. Answers will be displayed on the screen, where the numeric value within ()

indicates the confidence

interval of ∝1 and ∝2 at a confidence level of 90%.

*n1 and n2 are positive integers.

14 Zint1prop Finds the confidence interval of the success probability of a population from the success probability obtained from sample data collected from a population.

Example

A coin was tossed 100 times and landed head side up 42 times. Normally, the probability of head facing up is 0.5. Find the confidence interval of the success probability at a confidence level of 0.95.

1.Press SE14.

The parameter input screen will appear.

175