Write a fraction whose numerator and denominator add up to 9

blagie [28]

Point-slope form is y - y1 = m (x + x1)

First you need to find m [slope] by subtract y2 and y1 and divide it by the outcome of x2 - x1

13 - (-9) = 22
-2 - 9 = -11
22/-11 = -2

Plug in the first point (as instructed) into the equation.

y - (-9) = -2 (x - 9)

Simplify the beginning.

y + [9] = [-2] (x + [-9])

(The brackets are the fill in the blanks)

7 0

3 years ago

Let n1equals50, Upper X 1equals30, n2equals50, and Upper X 2equals10. Complete parts (a) and (b) below. a. At the 0.05 leve

Viefleur [7K]

Answer:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

$z=\frac{0.6-0.2}{\sqrt{0.4(1-0.4)(\frac{1}{50}+\frac{1}{50})}}=4.082$

$p_v =2*P(Z>4.082)=4.46x10^{-5}$

So the p value is a very low value and using any significance level for example $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion 1 is significantly different from proportion 2.

Step-by-step explanation:

1) Data given and notation

$X_{1}=30$ represent the number of people with a characteristic in 1

$X_{2}=10$ represent the number of people with a characteristic in 2

$n_{1}=50$ sample of 1 selected

$n_{2}=50$ sample of 2 selected

$p_{1}=\frac{30}{50}=0.6$ represent the proportion of people with a characteristic in 1

$p_{2}=\frac{10}{50}=0.2$ represent the proportion of people with a characteristic in 2

z would represent the statistic (variable of interest)

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

2) Concepts and formulas to use

We need to conduct a hypothesis in order to check if the proportion 1 is different from proportion 2 , the system of hypothesis would be:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{30+10}{50+50}=0.4$

3) Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.6-0.2}{\sqrt{0.4(1-0.4)(\frac{1}{50}+\frac{1}{50})}}=4.082$

4) Statistical decision

For this case we don't have a significance level provided $\alpha$ , but we can calculate the p value for this test.

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

$p_v =2*P(Z>4.082)=4.46x10^{-5}$

So the p value is a very low value and using any significance level for example $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion 1 is significantly different from proportion 2.

3 0

3 years ago

How many students tired out for the volleyball team is this a statistical or no

vodomira [7]

That question is not a statistical question since there will be only one answer. If it were to be statistical it would have multiple answers an example of that type of question would be, Why did you decide to try out for the volleyball team? This is statistical because some could say they joined for fun, credits, to do something active, etc.. there would be multiple answers. Your question, How many students tried out for the volleyball team isn't statistical since it will have one answer such as, 26 students, 15 student, 2 students, etc...

Hope this helped!

4 0

3 years ago

The width of a rectangle is 3 less than twice its length. if the area of the rectangle is 193 cm 2 cm2, what is the length of th

sineoko [7]

W=2L-3
W*L=193
replace W with 2L-3: (2L-3)L=193
2L^2-3L-193=0
Cannot factor
are you sure the numbers are correct?
If it cannot be factored, use the quadratic formula to find out L, then you can find out W
use the Pythagorean theorem to find the diagonal. I don't see an easier way.

4 0

3 years ago

Can anybody please help me with question 1 please...I would really appreciate it so much

In-s [12.5K]

Answer:

The total time the water balloon is in the air is 8 seconds. The balloon reaches the maximum height of 25 fee after 3 seconds. The water balloon has a height of 24 feet at 2 seconds and a half.

Step-by-step explanation:

5 0

3 years ago

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Write a fraction whose numerator and denominator add up to 9​

Write a fraction whose numerator and denominator add up to 9