Řešení - Statistics

Divide the sum by the number of terms:

Sum
$$896$$
Number of terms
$$3$$

$$x̄=\frac{896}{3}=298,667$$

The mean equals $$298,667$$

Arrange the numbers in ascending order:
128,256,512

Count the number of terms:
There are (3) terms

Because there is an odd number of terms, the middle term is the median:
128,256 512

The median equals 256

To find the range, subtract the lowest value from the highest value.

The highest value equals 512
The lowest value equals 128

$$512-128=384$$

The range equals 384

To find the sample variance, find the difference between each term and the mean, square the results, add together all of the squared results, and divide the sum by the number of terms minus 1.

The mean equals 298,667

To get the squared differences, subtract the mean from each term and square the result:

To get the sample variance, add together the squared differences and divide their sum by the number of terms minus 1

Sum:
$$45511 111+1820 444+29127 111=76458 666$$
Number of terms:
$$3$$
Number of terms minus 1:
2

Variance:
$$\frac{76458 666}{2}=38229 333$$

The sample variance ($$s^2$$) equals 38229,333

The standard deviation of the sample equals the square root of the sample variance. This is why the variance is usually represented by a squared variable.

Variance: $$s^2=38229,333$$

Find the square root:
$$s=\sqrt{\left(38229,333\right)}=195523$$

The standard deviation ($$s$$) equals 195 523