Question 4 of 10 What is i86 O A. -1 B. 1 O c. i O D. 1

Set A of six numbers has a standard deviation of 3 and set B of four numbers has a standard deviation of 5. Both sets of numbers

Alenkinab [10]

Given:

$\sigma_A=3$

$n_A=6$

$\sigma_B=5$

$n_B=4$

$\overline{x}_A=\overline{x}_B$

To find:

The variance. of combined set.

Solution:

Formula for variance is

$\sigma^2=\dfrac{\sum (x_i-\overline{x})^2}{n}$ ...(i)

Using (i), we get

$\sigma_A^2=\dfrac{\sum (x_i-\overline{x}_A)^2}{n_A}$

$(3)^2=\dfrac{\sum (x_i-\overline{x}_A)^2}{6}$

$9=\dfrac{\sum (x_i-\overline{x}_A)^2}{6}$

$54=\sum (x_i-\overline{x}_A)^2$

Similarly,

$\sigma_B^2=\dfrac{\sum (x_i-\overline{x}_B)^2}{n_B}$

$(5)^2=\dfrac{\sum (x_i-\overline{x}_B)^2}{4}$

$25=\dfrac{\sum (x_i-\overline{x}_B)^2}{4}$

$100=\sum (x_i-\overline{x}_B)^2$

Now, after combining both sets, we get

$\sigma^2=\dfrac{\sum (x_i-\overline{x}_A)^2+\sum (x_i-\overline{x}_B)^2}{n_A+n_B}$

$\sigma^2=\dfrac{54+100}{6+4}$

$\sigma^2=\dfrac{154}{10}$

$\sigma^2=15.4$

Therefore, the variance of combined set is 15.4.

7 0

3 years ago

Hop on the baby waveeeee. put your baby pic as your profile pic to make a trenddddd

Alex787 [66]

Answer:

I did it is in my profile

Step-by-step explanation:

8 0

4 years ago

4. Referring back to question 3. Determine the five vertices of the feasible region, given the constraints

erastova [34]

O( 0,0 ) A(9 , 0 ) D( 0,3 ) ( 9, 2) , ( 6 , 3 ) that are vertices of the feasible region.

What do math vertices mean?

The spots where two or more line segments or edges intersect are known as vertices in forms (like a corner). Vertex is the singular form of vertices.
For instance, a cone only has one vertex whereas a cube has eight. Although vertices are occasionally referred to as corners, the term "vertex" is preferable when discussing 2D and 3D designs.

The line 2x + 6y = 30

when x = 9 , 18 + 6y = 30

y = 2

So B = ( 9, 2)

So, C= ( b , 3 )

then , we can show O( 0,0 ) A(9 , 0 ) D( 0,3 )

Learn more about vertices

brainly.com/question/27029296

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7 0

1 year ago

If your on a plane going 1500 miles per hour, and a small window opens, would people get sucked in? wondering

Setler79 [48]

if they are just sitting its not likely but if they are standing especally if they like have there head out of the window yes and the speed if the wind would most likely tear you apart

7 0

3 years ago

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Find the sum: ( m 3 + 4n) + (3m – 2n+6)

sertanlavr [38]

Answer:

i would belive its 12 :D

Step-by-step explanation:

8 0

3 years ago

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