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3 years ago

Calculate the variance and the standard deviation of the data below 23. 19, 22, 30, 28

Mathematics

1 answer:

Alina [70]3 years ago

7 0

To get the variance, start with finding the mean of your data points:

(23 + 19 + 22 + 30 + 28) / 5 = 24.4

Now take each data point and subtract the mean from it, then square that value:

23 - 24.4 = -1.4 * -1.4 = 1.96

19 - 24.4 = -5.4 * -5.4 = 29.16

22 - 24.4 = -2.4 * -2.4 = 5.76

30 - 24.4 = 5.6 * 5.6 = 31.36

28 - 24.4 = 3.6 * 3.6 = 12.96

Now get the average of those new numbers. That is your variance:

(1.96 + 29.16 + 5.76 + 31.36 + 12.96) / 5 = 16.24

The standard deviation will be the square root of the variance:

√(16.24) = 4.0299 (rounded to 4DP)

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3 years ago

Read 2 more answers

A rectangular prism has dimensions of 2 ft, 4 ft, and 6 ft. If the dimensions are doubled, what would happen to the volume?

kondor19780726 [428]

Answer:

Volume is increased in a factor of 8. The volume is increased from $48\,ft^{3}$ to $384\,ft^{3}$ .

Step-by-step explanation:

The formula for the volume of the rectangular prism is:

$V = w\cdot h \cdot l$

Where:

$w$ - Width

$h$ - Height

$l$ - Length

If dimensions are doubled, then volume is increased in a factor of 8:

$V_{f} = (2\cdot w)\cdot (2\cdot h)\cdot (2\cdot l)$

$V_{f} = 8\cdot w \cdot h \cdot l$

$V_{f} = 8 \cdot V_{o}$

The volume is increased from $48\,ft^{3}$ to $384\,ft^{3}$ .

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3 years ago