Express 0.68 as a percent.

A cake is created by assembling two layers as shown in the diagram below. The exposed surfaces of the cake require frosting.

Hatshy [7]

Answer:

Step-by-step explanation:

352 is the answer

8 0

2 years ago

0 = 4x + 4 linear equation

FinnZ [79.3K]

Answer:

x = -1

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Step-by-step explanation:

Step 1: Define

0 = 4x + 4

Step 2: Solve for x

Subtract 4 on both sides: -4 = 4x
Divide 4 on both sides: -1 = x
Rewrite: x = -1

7 0

2 years ago

Dual-energy X-ray absorptiometry (DXA) is a technique for measuring bone health. One of the most common measures is total body b

sesenic [268]

Answer:

$\bar d=\frac{\sum_{i=1}^n d_i}{n}=-0.001$

$s=\sqrt{\frac{\sum_{i=1}^n (x_i -\bar X)^2}{n-1}}=0.0095$

-The sample is too small to make judgments about skewness or symmetry.

H0: $\mu_{1}=\mu_{2}$

H1: $\mu_{1} \neq \mu_{2}$

$t=\frac{1.173-1.174}{\sqrt{\frac{0.1506^2}{8}+\frac{0.1495^2}{8}}}=-0.013$

$p_v =2*P(t_{(14)}$

So the p value is a very high value and using any significance level for example $\alpha=0.05, 0,1,0.15$ always $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and a we don't have a significant difference between the two means.

Step-by-step explanation:

First we need to find the difference defined as:

(Operator 1 minus Operator 2)

d1=1.326-1.323=0.003 d2=1.337-1.322=0.015

d3=1.079-1.073=0.006 d4=1.229-1.233=-0.004

d5=0.936-0.934=0.002 d6=1.009-1.019=-0.01

d7=1.179-1.184=-0.005 d8=1.289-1.304=-0.015

Now we can calculate the mean of differences given by:

$\bar d=\frac{\sum_{i=1}^n d_i}{n}=-0.001$

And for the sample deviation we can use the following formula:

$s=\sqrt{\frac{\sum_{i=1}^n (x_i -\bar X)^2}{n-1}}=0.0095$

Describe the distribution of these differences using words. (which one is correct)

We can plot the distribution of the differences with the folowing code in R

differences<-c(0.003,0.015,0.006,-0.004,0.002,-0.01,-0.005,-0.015)

hist(differences)

And we got the image attached. And we can see that the distribution is right skewed but we don't have anough info to provide a conclusion with just 8 differnences.

-The sample is too small to make judgments about skewness or symmetry.

Use a significance test to examine the null hypothesis that the two operators have the same mean. Give the test statistic. (Round your answer to three decimal places.)

$\bar X_{1}=1.173$ represent the mean for the operator 1

$\bar X_{2}=1.174$ represent the mean for the operator 2

$s_{1}=0.1506$ represent the sample standard deviation for the operator 1

$s_{2}=0.1495$ represent the sample standard deviation for the operator 2

$n_{1}=8$ sample size for the operator 1

$n_{2}=8$ sample size for the operator 2

t would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the means for the two groups are the same, the system of hypothesis would be:

H0: $\mu_{1}=\mu_{2}$

H1: $\mu_{1} \neq \mu_{2}$

If we analyze the size for the samples both are less than 30 so for this case is better apply a t test to compare means, and the statistic is given by:

$t=\frac{\bar X_{1}-\bar X_{2}}{\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}}$ (1)

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the statistic

We can replace in formula (1) like this:

$t=\frac{1.173-1.174}{\sqrt{\frac{0.1506^2}{8}+\frac{0.1495^2}{8}}}=-0.013$

Statistical decision

For this case we don't have a significance level provided $\alpha$ , but we can calculate the p value for this test. The first step is calculate the degrees of freedom, on this case:

$df=n_{1}+n_{2}-2=8+8-2=14$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{(14)}$

So the p value is a very high value and using any significance level for example $\alpha=0.05, 0,1,0.15$ always $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and a we don't have a significant difference between the two means.

8 0

3 years ago

I NEED HELP ASAP 85 POINTS At a bargain store, Tanya bought 5 items that each cost the same amount. Tony bought 3 items that eac

Andrei [34K]

Answer:

Step-by-step explanation:

A) 5x = 3(x - 2.5)

-----------------------

B)

Distribute

5x = 3x - 7.5

Subtract 3x from both sides

2x = -7.5

Divde both sides by 2

x = -3.75

-----------------------

C)

5 * (-3.75) = 3(-3.75 - 2.5)

-18.75 = -18.75

D)

Tanya paid –$3.75 for each of 5 items

Tony paid –$6.25 for each of 3 items

There seems to be an error in the question since the cost of items is negative

Tony bought fewer items and paid less for each.

5 0

2 years ago

What ethical issues have been raised by the scientific community's commitment to ensuring that experimental treatments are not

e-lub [12.9K]

Answer:

They include;

1. Fewer chances of determining how effective the treatment plan would be.

2. Inability of every patient to access the experimental treatment.

3. Difficulties in making knowledgeable decisions on the treatment plan.

4. Determining that the experimental treatments are offered with the right motive.

Step-by-step explanation:

In medical treatment administration, it is standard practice that drugs undergo clinical trials on test animals before they are administered to patients. However, some sicknesses are without known drugs for treatment or may have drugs that are still undergoing experiments and trials. In such cases, patients may want to be treated with experimental drugs.

Ethical issues such as the above-listed can arise from this. The foremost of them all is the fact that the treatment might prove ineffective thus causing more problems to the patient.

8 0

2 years ago