Sharp EL-531LH - Page 32

Mastering the Calculator using the Sharp EL-531LH 29
Note: Check that you have cleared all previous data. Press
The keystrokes required are:
The display should read n = 30
Press and the display should read 61.766667 as the mean
Press and the display should read 1.1943353 as the sample standard deviation s
and the display should read 1.4264369 as the variance s
2
Thus, as expected
s = 1.2 kg, s
2
= 1.4 kg
2
and = 61.8 kg
Exercise 6
Find the mean, standard deviation and variance of
(a) The annual rainfall data for the years 1971 – 1990
Note: For the EL-531GH, the key strokes are
Ye ar 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980
Rain
(mm)
1 340 990 1 120 1 736 260 1 100 1 379 1 125 1 430 1 446
Ye ar
1981 1982 1983 1984 1985 1986 1987 1988 1989 1990
Rain
(mm)
1 459 1 678 1 345 978 1 002 1 110 1 546 1 672 1 467 1 123
x
x