How do I solve this?

Answer:

The test statistic is z = -2.11.

Step-by-step explanation:

Before finding the test statistic, we need to understand the central limit theorem and subtraction of normal variables.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

Group 1: Sample of 35, mean of 1276, standard deviation of 347.

This means that:

[tex]\mu_1 = 1276, s_1 = \frac{347}{\sqrt{35}} = 58.6537[/tex]

Group 2: Sample of 35, mean of 1439, standard deviation of 298.

This means that:

[tex]\mu_2 = 1439, s_2 = \frac{298}{\sqrt{35}} = 50.3712[/tex]

Test if there is a difference in productivity level.

At the null hypothesis, we test that there is no difference, that is, the subtraction is 0. So

[tex]H_0: \mu_1 - \mu_2 = 0[/tex]

At the alternate hypothesis, we test that there is difference, that is, the subtraction is different of 0. So

[tex]H_1: \mu_1 - \mu_2 \neq 0[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{s}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis and s is the standard error.

0 is tested at the null hypothesis:

This means that [tex]\mu = 0[/tex]

From the two samples:

[tex]X = \mu_1 - \mu_2 = 1276 - 1439 = -163[/tex]

[tex]s = \sqrt{s_1^2+s_2^2} = \sqrt{58.6537^2+50.3712^2} = 77.3144[/tex]

Test statistic:

[tex]z = \frac{X - \mu}{s}[/tex]

[tex]z = \frac{-163 - 0}{77.3144}[/tex]

[tex]z = -2.11[/tex]

The test statistic is z = -2.11.

when you divide -8/2=-4 and 2/2=1

-4<1

when you divide by a negative number your sign changes

4>-1

When you multiply or divide each side by 2, the signs stay the same. −16 < 4 and −4 < 1. When you multiply or divide by −2, the inequality sign reverses. 16 > −4 and 4 > −1.

Answer:

see below

Step-by-step explanation:

When multiplying or dividing an inequality by a positive, the inequality remains the same direction

3x < 6

Divide by 3

3x/3 < 6/3

x <2

When multiplying or dividing an inequality by a negative, the inequality changes direction

-3x < 6

-3x/ -3 > 6/-3

x > -2

search up mean calculator

Answer:

it should be 40 in.

Step-by-step explanation:

because you have to use pythagorean theorem which is A square plus B square equals C square

Hope it helps.

Answer: A

Step-by-step explanation:

4.7+2.8 = 7.5

And

7.5 -4.7 = 2.8

Answer:

48 m³

4,186.67 km³

Step-by-step explanation:

volume of pyramid =

⅓×6×6×4 = 48 m³

volume of ball =

4/3 × 3.14 × 10³ = 4,186.67 km³

Answer:

[tex]Area = 24\ in^2[/tex]

Step-by-step explanation:

Given

Let

[tex]a, b \to[/tex] opposite sides of each trapezoid

[tex]h \to[/tex] height

[tex]a = 2; \ \ \ b = 4 \ \ \ \ h = 2[/tex]

See attachment for trapezoids

Required

The combined area of the 4

First, we calculate the area of 1

[tex]Area = \frac{1}{2}(a + b) * h[/tex]

So:

[tex]A_1 = \frac{1}{2}(2 + 4) * 2[/tex]

[tex]A_1 = \frac{1}{2}*6 * 2[/tex]

Using a calculator

[tex]A_1 = 6[/tex]

The combined area is:

[tex]Area =n * A_1[/tex]

Where

[tex]n = 4[/tex] --- 4 blades

So:

[tex]Area = 4 * 6[/tex]

[tex]Area = 24\ in^2[/tex]

Answer:

3. B

4. B

5. C

Step-by-step explanation:

Answer:

MK bisects <LKN

Step-by-step explanation:

We can already say two sets of sides are equal; LK = NK because it is given and MK = MK because of reflexive property. In order to use Side-Angle-Side, we need to prove the angles between the sides are congruent. This means <LKM and <NKM. The only option that would help is with the is the lat option, MK bisects <LKN because, then we could say <LKM and NKM are congruent because MK would be an angle bisector. This is exactly what we want, so the answer is MK bisects <LKN.

I'm still doing the rest but number 1 is D

Answer:

your answer is 41.6667

Answer:

41 2/3 yards

Step-by-step explanation:

Divide by 3 because 3ft in one yard

125 / 3 = 41 2/3 yards

If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K