written 2.4 years ago by |
[1] Centro-id method.
Computation of $x^x$
Area segment No | Area (A) | $ \bar x$ | $A( \bar x )$ |
---|---|---|---|
1 | $\frac{1}{2} \times 0.3 \times 1 = 0.15$ | $\frac{0 + 1 + 1}{3} = 0.67$ | 0.1005 |
2 | $2.5 \times 3 = 0.78$ | (1 + 3.6) 12 = 2.3 | 1.794 |
3 | $0.4 \times 0.3 = 0.12$ | (3.6 + 4) 12 = 3.8 | 0.456 |
4 | $\frac{1}{2} \times 0.4 \times 0.2 = 0.04$ | 3.8667 | 0.1547 |
5 | $1.5 \times 0.5 = 0.75$ | 4.75 | 3.56 |
6 | $0.5 \times 0.5 = 0.25$ | 5.75 | 1.4375 |
7 | $\frac{1}{2} \times 0.5 \times 0.5 = 0.125$ | 5.833 | 0.729 |
8 | $1 \times 1 = 1$ | 6.5 | 6.5 |
9 | $\frac{1}{2} \times 1 \times 1 = 0.5$ | 7.33 | 3.665 |
$x^* = \frac{\sum a ( \bar X)}{\sum A} = \frac{18.3967}{3.7} = 4.9$
[b] Weighted Average : (valid for symmetric mean)
$ x^* = \frac{2.5 * 0.3 + 5 \times 0.5 + 6.5 * 1}{0.3 + 0.5 + 1}$
= 5.41
[c] Centre of sums:
Area of $A_1$ = $\frac{1}{2} \times 0.3 \times 1 + 3 \times 0.3 + \frac{1}{2} \times 1 \times 0.3$
= 0.15 + 0.9 + 0.15
= 1.2
Area of $A_2$ = $\frac{1}{2} \times 1 \times 0.5 + 2 \times 0.5 + \frac{1}{2} \times 1 + 0.5$
= 0.25 + 1.0 + 0.25
= 1.5
Area of $A_3$ = $\frac{1}{2} \times 1 \times 1 + 1 \times 1 + \frac{1}{2} \times 1 \times 1$
$ = \frac{1}{2} + 1 + \frac{1}{2} = 2$
$x^x = \frac{1.2 * 2.5 + 1.5 * 5 + 2 * 6.5}{1.2 + 1.5 + 2}$
$= \frac{23.5}{4.7} = 5$
[d] First of maxima (last of maxima):
$A_3$ is having the largest area.
First of maxima = 6 Last of maxima 7
$x^* = \frac{6 + 7}{2} = 6.5$