Which expression gives the closest estimate of 228

I’ll give brainliest IF ITS AN ACRUAL ANSWER, ALL USELESS ONES WILL BE REPORTED

Llana [10]

Answer:

C

Step-by-step explanation:

pls mark brainliest

multiply the numerator and denominator by the same number so, that all the fractions have a denominator of 12.

4 0

3 years ago

Read 2 more answers

3k - 2c + 8 use k = 7 and c = 4

Inga [223]

Answer:

21

Step-by-step explanation:

3 (7) - 2(4) + 8

21 - 8 + 8

13 + 8

21

6 0

2 years ago

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An 18-foot ladder touches a building 14 feet up the wall. What is the angle measure, to the nearest degree, of the ladder to the

kondor19780726 [428]

Trigonometry can be used to find angles and sides of simple triangles. If an 18-foot ladder touches a building 14 feet up the wall then the angle can be deduced by trigonometry. In this case, the ladder defines the hypotenuse (H) of the triangle and the wall defines the opposite (O) side of the triangle. Therefore we can use the equation theta=sin^-1(O/H) . This yields an angle of 51 degrees.

5 0

2 years ago

Given f (x)=-3x+4 what is f (-4) a.-40 b.-22 c.-1 d.40

FinnZ [79.3K]

F(x)=-3(x)+4
Therefore this implies that we must put the -4 where we see an X on the equation
F(-4)=-3(-4)+4
=16

6 0

2 years ago

Consider a chemical company that wishes to determine whether a new catalyst, catalyst XA-100, changes the mean hourly yield of i

kolezko [41]

Answer:

Null hypothesis: $\mu = 750$

Alternative hypothesis: $\mu \neq 750$

$t=\frac{811-750}{\frac{19.647}{\sqrt{5}}}=6.943$

$p_v =2*P(t_{4}>6.943)=0.00226$

If we compare the p value and a significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the actual true mean is significantly different from 750 pounds per hour.

Step-by-step explanation:

Data given and notation

Data: 801, 814, 784, 836,820

We can calculate the sample mean and sample deviation with the following formulas:

$\bar X =\frac{\sum_{i=1}^n X_i}{n}$

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

$\bar X=811$ represent the sample mean

$s=19.647$ represent the standard deviation for the sample

$n=5$ sample size

$\mu_o =750$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses to be tested

We need to conduct a hypothesis in order to determine if the mean is different from 750 pounds per hour, the system of hypothesis would be:

Null hypothesis: $\mu = 750$

Alternative hypothesis: $\mu \neq 750$

Compute the test statistic

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

We can replace in formula (1) the info given like this:

$t=\frac{811-750}{\frac{19.647}{\sqrt{5}}}=6.943$

Now we need to find the degrees of freedom for the t distirbution given by:

$df=n-1=5-1=4$

What do you conclude?

Compute the p-value

Since is a two tailed test the p value would be:

$p_v =2*P(t_{4}>6.943)=0.00226$

If we compare the p value and a significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the actual true mean is significantly different from 750 pounds per hour.

4 0

3 years ago

Which expression gives the closest estimate of 228 – 179?