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How many solutions dose the equation 5x + 3x -4 =10 A.0 B.1 C.2 D. Indefinitely many

Gnesinka [82]

Answer:

The answer is 14/8

Step-by-step explanation:

3 0

3 years ago

Most US adults have social ties with a large number of people, including friends, family, co-workers, and other acquaintances. I

xxTIMURxx [149]

Answer:

$t=\frac{669-634}{\frac{732}{\sqrt{1700}}}=1.971$

$p_v =2*P(t_{(1699)}>1.971)=0.049$

If we compare the p value and the significance level given $\alpha=0.1$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is different from 634 at 10% of signficance.

Step-by-step explanation:

Data given and notation

$\bar X=669$ represent the sample mean

$s=732$ represent the sample standard deviation

$n=1700$ sample size

$\mu_o =68$ represent the value that we want to test

$\alpha=0.$ 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.

We need to conduct a hypothesis in order to check if the mean is different from 634, the system of hypothesis would be:

Null hypothesis: $\mu = 634$

Alternative hypothesis: $\mu \neq 634$

If we analyze the size for the sample is > 30 but we don't know the population deviation so 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".

Calculate the statistic

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

$t=\frac{669-634}{\frac{732}{\sqrt{1700}}}=1.971$

P-value

The first step is calculate the degrees of freedom, on this case:

$df=n-1=1700-1=1699$

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

$p_v =2*P(t_{(1699)}>1.971)=0.049$

Conclusion

If we compare the p value and the significance level given $\alpha=0.1$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is different from 634 at 10% of signficance.

3 0

3 years ago

Surface Area of Cylinder=2πrh+2πr2

Alex

Find the surface area when r is 8 inches and h is 8 inches.

$\qquad$ A. 160π in²

$\qquad$ B. 154π in²

$\qquad$ C. 288π in²

$\qquad$ D. 256π in² ☑

We are given –

$\qquad$ ⇢Radius of cylinder , r = 8 inches

$\qquad$ ⇢ Height of cylinder, h = 8 inches.

We are asked to find surface area of the given cylinder.

Formula to find the surface cylinder given by –

$\bf \star \pink{ Surface\: Area_{(Cylinder)} = 2\pi rh +2\pi r^2 }$

Now, Substitute given values –

$\sf \twoheadrightarrow Surface\: Area_{(Cylinder)} = 2\pi rh +2\pi r^2$

$\sf \twoheadrightarrow Surface\: Area_{(Cylinder)} = 2 \pi \times 8 \times 8 + 2\pi \times 8^2$

$\sf \twoheadrightarrow Surface\: Area_{(Cylinder)} = 2 \pi \times 8^2 + 2\pi \times 8^2$

$\sf \twoheadrightarrow Surface\: Area_{(Cylinder)} = 2\pi \times 64 +2\pi \times 64$

$\sf \twoheadrightarrow Surface\: Area_{(Cylinder)} =128 \pi + 128\pi$

$\purple{\bf \twoheadrightarrow Surface\: Area_{(Cylinder)} = 256\pi \: in^2 }$

Henceforth,Option D is the correct answer.

8 0

2 years ago

I need to know the answer to this?

iris [78.8K]

Answer:

5 min person wit 10 min person

5 min person wit 20 min person and 5 min person back

5 min person wit 25 min person and 5 min person back

5 min person need to slow down ea. time

5 0

3 years ago

How many significant figures will be in the answer when you multiply 3.4 x 4.56?

steposvetlana [31]

There are 2 before the decimal point because 3×4=12 and 12 has two digits.
There are 3 after the decimal point because we add together the number of digits after the decimal point in the operands, which is 1 plus 2=3. In all then there are 2+3=5 significant figures.

6 0

3 years ago