# Statistic

Please help me with statistic I have listed an attachment I need to do Practice Problem 11, 12, 13, & 16 in the corresponding spaces below. Round your answers to 3 decimal places.

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11) For the following scores, find the (a) mean, (b) median, (c) sum of squared deviations, (d) variance, and (e) standard deviation:

2, 2, 0, 5, 1, 4, 1, 3, 0, 0, 1, 4, 4, 0, 1, 4, 3, 4, 2, 1, 0

So the mean would be: You add up all of the numbers, and divide by 21

= 42/21 = 2

The median is the number in the middle. So we first have to put the numbers in order from lowest to highest

0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3 4, 4, 4, 4, 4, ,5

There are 21 numbers, so the middle number is 11. The 11th number is 2 so that is the median

The sum of squares deviations

The formula is:

The sum of (each number - the mean) squared

(x-mean)squared

0 -2 4

0 -2 4

0 -2 4

0 -2 4

0 -2 4

1 -1 1

1 -1 1

1 -1 1

1 -1 1

1 -1 1

2 0 0

2 0 0

2 0 0

3 1 1

3 1 1

4 2 4

4 2 4

4 2 4

4 2 4

4 2 4

5 3 9

sum 56

Variance

To get variance it is the sum we got of the sum of squares deviations, /the sample size

= 52/21 = 2.476

Standard deviation is simply the square root of the variance = 1.57

12) For the following scores, find the (a) mean, (b) median, (c) sum of squared deviations, (d) variance, and (e) standard deviation:

1,112; 1,245; 1,361; 1,372; 1,472

So the mean would be: You add up all of the numbers, and divide by 5

= 6,562/5 = 1,312

The median is the number in the middle. So we first have to put the numbers in order from lowest to highest

1,112

1,245

1,361

1,372

1,472

There are 5 numbers, so the middle number is 3. The 3rd number ...