I really need help with this please I keep getting it wrong and I’m confused

Determine if events A and B are mutually exclusive.

gladu [14]

Answer:

A) Not mutually exclusive

Step-by-step explanation:

Given

$P(A) = \frac{1}{4}$

$P(B) = \frac{3}{5}$

$P(A\ or\ B) = \frac{7}{10}$

Required

Determine if they are mutually exclusive or not

Mutually exclusive are defined by:

$P(A\ or\ B) = P(A) + P(B)$

So, we have:

$P(A\ or\ B) = \frac{1}{4} + \frac{3}{5}$

Take LCM

$P(A\ or\ B) = \frac{5+12}{20}$

$P(A\ or\ B) = \frac{17}{20}$

By comparing:

$P(A\ or\ B) = \frac{17}{20}$ ---- Calculated

$P(A\ or\ B) = \frac{7}{10}$ ---- Given

We can conclude that A and B are not mutually exclusive because:

$\frac{17}{20} \ne \frac{7}{10}$

6 0

3 years ago

Solve for x -7(1-8x)=105

Sunny_sXe [5.5K]

-7 + 56x = 105
56x = 105 + 7
56x = 112
x = 2

4 0

4 years ago

Solve the system of equations. 3x+4y=−23 x=3y+1 x= y=

Romashka-Z-Leto [24]

Answer:

i think {x,y} = {-5,-2}

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

Please help! I don't understand how to solve this problem

Ilia_Sergeevich [38]

Using the z-distribution, a sample of 142,282 should be taken, which is not practical as it is too large of a sample.

<h3>What is a z-distribution confidence interval?</h3>

The confidence interval is:

$\overline{x} \pm z\frac{\sigma}{\sqrt{n}}$

The margin of error is:

$M = z\frac{\sigma}{\sqrt{n}}$

In which:

$\overline{x}$ is the sample mean.

z is the critical value.

n is the sample size.

$\sigma$ is the standard deviation for the population.

Assuming an uniform distribution, the standard deviation is given by:

$S = \sqrt{\frac{(4 - 0)^2}{12}} = 1.1547$

In this problem, we have a 95% confidence level, hence $\alpha = 0.95$ , z is the value of Z that has a p-value of $\frac{1+0.95}{2} = 0.975$ , so the critical value is z = 1.96.

The sample size is found solving for n when the margin of error is of M = 0.006, hence:

$M = z\frac{\sigma}{\sqrt{n}}$

$0.006 = 1.96\frac{1.1547}{\sqrt{n}}$

$0.006\sqrt{n} = 1.96 \times 1.1547$

$\sqrt{n} = \frac{1.96 \times 1.1547}{0.006}$

$(\sqrt{n})^2 = \left(\frac{1.96 \times 1.1547}{0.006}\right)^2$

n = 142,282.

A sample of 142,282 should be taken, which is not practical as it is too large of a sample.

More can be learned about the z-distribution at brainly.com/question/25890103

#SPJ1

8 0

1 year ago

Find the volume of the given solid: Bounded by the cylinder y^2+z^2=4 and the planes x = 2y, x = 0, z = 0 in the first octant.

rodikova [14]

The solution would be like this for this specific problem:

V = ∫ dV 
= ∫0→2 ∫ 0→π/2 ∫ 0→ 2·r·sin(φ) [ r ] dzdφdr 
= ∫0→2 ∫ 0→π/2 [ r·2·r·sin(φ) - r·0 ] dφdr 
= ∫0→2 ∫ 0→π/2 [ 2·r²·sin(φ) ] dφdr 
= ∫0→2 [ -2·r²·cos(π/2) + 2·r²·cos(0) ] dr 
= ∫0→2 [ 2·r² ] dr 
= (2/3)·2³ - (2/3)·0³ 
= 16/3

So the volume of the given solid is 16/3. I am hoping that these answers have satisfied your query and it will be able to help you in your endeavors, and if you would like, feel free to ask another question.

3 0

4 years ago