What is the perimeter of quadrilateral ABCD?

Kayden brought 9 packs of paper for $27 how much will you pay for 11 packs of paper

zhuklara [117]

Answer: $33

Step-by-step explanation: Divide 27/9 which is $3

-so you pay $3 for each pack

-then to find how much you need to pay for 11 packs you just multiply 11*3=33

5 0

4 years ago

In this experiment researchers randomly assigned smokers to treatments. Of the 193 smokers taking a placebo, 29 stopped smoking

mezya [45]

Answer:

The estimated standard error for the sampling distribution of differences in sample proportions is 0.0382.

Step-by-step explanation:

To solve this question, we need to understand the Central Limit Theorem and subtraction of normal variables.

Central Limit Theorem

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

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

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean $\mu = p$ and standard deviation $s = \sqrt{\frac{p(1-p)}{n}}$

Subtraction of normal variables:

When we subtract normal variables, the mean is the subtraction of the means, while the standard error is the square root of the sum of the variances:

Of the 193 smokers taking a placebo, 29 stopped smoking by the 8th day.

This means that:

$p_S = \frac{29}{193} = 0.1503$

$s_S = \sqrt{\frac{0.1503*0.8497}{193}} = 0.0257$

Of the 266 smokers taking only the antidepressant buproprion, 82 stopped smoking by the 8th day.

This means that:

$p_A = \frac{82}{266} = 0.3083$

$s_A = \sqrt{\frac{0.3083*0.6917}{266}} = 0.0283$

Calculate the estimated standard error for the sampling distribution of differences in sample proportions.

$s = \sqrt{s_S^2 + s_A^2} = \sqrt{0.0257^2 + 0.0283^2} = 0.0382$

The estimated standard error for the sampling distribution of differences in sample proportions is 0.0382.

7 0

3 years ago

Really need this, click on photo to see the whole thing

leonid [27]

Nansennsndkeksnndneodje

6 0

3 years ago

HELP! What does DF equal? WILL GIVE BRAINLIEST!

olga2289 [7]

the answer is 30 because CE equals 60 and DE equals 30 and DF is the same length as DE

6 0

3 years ago

Given △ABC. m∠A>m∠B>m∠C. Perimeter=30. Which side of △ABC may have length 7?

lisabon 2012 [21]

<u>Solution-</u>

As given in △ABC,

$m\angle A>m\angle B>m\angle C$

As from the properties of trigonometry we know that, the greater the angle is, the greater is the value of its sine. i.e

$\sin A>\sin B>\sin C$

According to the sine law,

$\frac{a}{\sin A}=\frac{b}{\sin B}=\frac{c}{\sin C}$

In order to make the ratio same, even though m∠A>m∠B>m∠C, a must be greater than b and b must be greater than c.

$\Rightarrow a>b>c$

Also given that its perimeter is 30. Now we have to find out whose side length is 7. So we have 3 cases.

Case-1. Length of a is 7

As a must be the greatest, so b and c must be less than 7. Which leads to a condition where its perimeter won't be 30. As no 3 numbers less than 7 can add up to 30.

Case-2. Length of b is 7

As b is greater than c, so c must 6 or less than 6. But in this case the formation of triangle is impossible. Because the triangle inequality theorem states that the sum of any 2 sides of a triangle must be greater than the measure of the third side. If b is 7 and c is 6, then a must be 17. So no 2 numbers below 7 can add up to 17.

Case-3. Length of c is 7

As this is the last case, this must be true.

Therefore, by taking the aid of process of elimination, we can deduce that side c may have length 7.

5 0

4 years ago