Sharp EL-531LH Mastering Instructions page 32

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
Thus, as expected
2
s = 1.2 kg, s = 1.4 kg
Exercise 6
Find the mean, standard deviation and variance of
(a) The annual rainfall data for the years 1971 – 1990
Year 1971 1972
1 340 990
Rain
(mm)
1981 1982
Year
1 459 1 678
Rain
(mm)
Note: For the EL-531GH, the key strokes are
Mastering the Calculator using the Sharp EL-531LH
2
x
and = 61.8 kg
1973 1974 1975
1 120 1 736 260
1983 1984 1985
1 345 978 1 002
x
2
1976 1977 1978
1 100 1 379 1 125
1986 1987 1988
1 110 1 546 1 672
29
1979 1980
1 430 1 446
1989 1990
1 467 1 123