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All 6 members of a family work. Their hourly wages (in dollars) are the following.

20, 30, 13, 10, 22, 37
Assuming that these wages constitute an entire population, find the standard deviation of the population. Round your answer to two decimal places

User Rmaleki
by
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1 Answer

5 votes

Answer:

Explanation:

σ = sqrt [ Σ ( xi - μ )^2 / N ]

where:

σ is the standard deviation

Σ is the sum of the values

xi is the value of the i-th observation

μ is the mean of the population

N is the number of observations

First, we need to find the mean of the population:

μ = (20 + 30 + 13 + 10 + 22 + 37) / 6

μ = 132 / 6

μ = 22

Next, we can calculate the deviations of each observation from the mean:

20 - 22 = -2

30 - 22 = 8

13 - 22 = -9

10 - 22 = -12

22 - 22 = 0

37 - 22 = 15

Then, we square each deviation:

(-2)^2 = 4

8^2 = 64

(-9)^2 = 81

(-12)^2 = 144

0^2 = 0

15^2 = 225

We add up the squared deviations:

4 + 64 + 81 + 144 + 0 + 225 = 518

We divide by the number of observations and take the square root:

σ = sqrt [ Σ ( xi - μ )^2 / N ]

σ = sqrt (518 / 6)

σ ≈ 10.72

Therefore, the standard deviation of the population is approximately 10.72 dollars.

User Slant
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