Sharp EL-9900 - Manual (Page 184)

174
Chapter 10: Statistics & Regression Calculations
3. Press @ h.
Answers will be displayed on
the screen, where P
^
indi-
cates the calculated success
rate of the data combined
with sample data 1 and 2,
and P
^
1
and P
^
2
show the success rates of sample data 1 and 2,
respectively. n
1
and n
2
are positive integers.
12 Zint1samp Finds the confidence interval of a population mean, µ.
Example
The average weight of a newly developed product is known to be
52.4 g and standard deviation ( σ) is 4.5. Given the average
weight of 20 units is 53.4 g (x), find the confidence interval of the
data where the level of confidence (C-level) is 0.95.
Set the input method to value input mode
1. Press # S E 1 7 E.
2. Press S E 1 2.
The 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
numerical value within ()
indicates the confidence
interval with the level of
confidence at 0.95, that is, the confidence interval of this
sample data with the confidence level of 95% is between
51.427… and 55.372….
C-level indicates the level of confidence and n is a positive
integer.