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3 years ago

Find the sample variance and standard deviation of: 21, 12, 3, 9, 11s2=?

Mathematics

1 answer:

olga nikolaevna [1]3 years ago

8 0

Answer:

42. 2

6.496

Step-by-step explanation:

Given the data :

21, 12, 3, 9, 11

Variance :

S² = Σ(x - m)² ÷ (n - 1)

n = sample size = 5

m = sample mean = Σx / n

m = (21 + 12 + 3 + 9 + 11) / 5

m = 11. 2

(21-11.2)² + (12 -11.2)² + (3 - 11.2)² + (9-11.2)²

+ (11-11.2)² / (5 - 1)

S² = 42.2

Standard deviation, s = sqrt(42.2) = 6.496

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PSYCHO15rus [73]

Answer:

3 - 3/5

Step-by-step explanation:

Cosine = adjacent/hypotenuse

So, in this case, cos=6/10=3/5

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3 years ago

A cosmetic factory has 630 employees.

OleMash [197]

Answer:

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Step-by-step explanation:

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3 years ago

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Find the median and mean of 21, 0, 36, 30, 13, 32

Alexandra [31]

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3 years ago

In order to test for the significance of a regression model involving 4 independent variables and 47 observations, the numerator

Karolina [17]

Answer:

c. 4 and 42

Step-by-step explanation:

Given

$p = 4$ -- independent variables

$n = 47$ ---- observations

Required

The numerator and denominator degrees of freedom

The denominator degrees of freedom is:

$df =n - p - 1$

$df =47 - 4 - 1$

$df =42$

For the numerator, we have:

$df = p$

$df = 4$

8 0

3 years ago

Jayanta is raising money for the? homeless, and discovers each church group requires 2 hr of letter writing and 1 hr of? follow-

boyakko [2]

Answer:

Jayanta needs 2 labor union groups and 8 church groups.

Step-by-step explanation:

Let c denotes churches .

Let l denotes labor unions.

We know that Jayanta can only spend 20 hours letter writing and 14 hour of follow-up.

So, equations becomes:

$2c+2l=20$

$c+3l=14$

And total money raised can be shown by = $150c+175l$

We have to maximize $150c+175l$ keeping in mind that $2c+2l \leq 20$ and $c+3l \leq 14$

We will solve the two equations: $2c+2l=20$ and $c+3l=14$

We get l = 2 and c = 8

And total money raised is $150\times8 + 175\times2$ = $1200+350=1550$ dollars.

Hence, Jayanta needs 2 labor union groups and 8 church groups.

8 0

3 years ago