Download USING THE T1-82 FOR STATISTICS sheet 2

USING THE T1-82 FOR STATISTICS
sheet 2
CALCULATING MEAN, MEDIAN, QUARTILES, VARIANCE
eg:
x
f
0
4
1
12
2
33
DATA IN FORM OF
A FREQUENCY
DISTRIBUTION
Press STAT button, then EDIT , ENTER
( one variable)
Enter your x values into L1
Enter the frequencies into L2
L1
L2
0
1
2
3
4
12
33
26
L3
L4
L5
3
26
L6
Press STAT button, across to CALC, down to 1 - Var Stats, ENTER
1 - Var Stats appears on the screen, put in L1 , L2 press ENTER
(note you must put a comma between L1 and L2 )
Check your value of n
This gives:
x  2.08
 x  156
 x  378
2
sample mean
sum of x
sum of x 2
Sx  0.8504... sample standard deviation
 x  0.8447... population standard deviation
n  75
minX  0
Q1  2 lower quartile
Med  2
median
Q3  3 upper quartile
maxX  3
population

mean
FORMULA FOR CALCULATING
THE MEAN:
x
sample mean
 fx
f
fx
f
FORMULA FOR CALCULATING STANDARD DEVIATION:
population standard deviation
sample ' standard deviation '

 f (x  )
n
2
n   f (x  ) 
s


n  1 
n

(unbiased
estimate of population standard
Note: variance = (standard deviation)2
 fx
2

n
2
 2
where n   f
deviation)