By what number should 1 1/2 be divided to get 2/3 ? *

The population of cats in a rural neighborhood has declined in the last year by roughly 30%. Residents hypothesize that this is

zvonat [6]

Answer:

Orinal number of cats= 171

Step-by-step explanation:

Giving the following information:

Decrease in population= 30%

Current population= 120

<u>To calculate the original number of cats, we need to use the following formula:</u>

Orinal number of cats= current population / (1 - decrease)

Orinal number of cats= 120 / (1 - 0.3)

Orinal number of cats= 171

8 0

3 years ago

What is the equation of the line that is parallel to the line y =-1\3

PilotLPTM [1.2K]

Hello!

If a you want to find an equation of the line that is parallel to the given line, we must know that if two lines are parallel, then their slope will <em>always</em> have to be equal.

This means that the new equation must have a slope of -1/3.

Also, you would need to substitute the given point (6, 8) into the equation with the slope: -1/3 as well. Following these steps allows you to find the equation of line.

y = -1/3x + b (6, 5)

5 = -1/3(6) + b

5 = -2 + b (add 2 to both sides)

7 = b

Therefore, the equation of the line is y = -1/3x + 7.

5 0

3 years ago

Solve this equation 3+5/2x=1/2x-8

guajiro [1.7K]

Answer:

34

Step-by-step explanation:

3 0

3 years ago

In a study of 420,095 Danish cell phone users, 135 subjects developed cancer of the brain or nervous system (based on data from

Maksim231197 [3]

Answer:

$z=\frac{0.0003214 -0.00034}{\sqrt{\frac{0.00034(1-0.00034)}{420095}}}=-0.654$

$p_v =2*P(Z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.005$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can say that the true proportion not differs significantly from the specified value of 0.00034 or 0.034%.

Step-by-step explanation:

1) Data given and notation

n=420095 represent the random sample taken

X=135 represent the subjects developed cancer of the brain or nervous system (based on data from the Journal of the National Cancer Institute as reported in USA Today)

$\hat p=\frac{135}{420095}=0.0003214$ estimated proportion of subjects developed cancer of the brain or nervous system (based on data from the Journal of the National Cancer Institute as reported in USA Today)

$p_o=0.00034$ is the value that we want to test

$\alpha=0.005$ represent the significance level

Confidence=99.5% or 0.995

z would represent the statistic (variable of interest)

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

2) Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the brain or nervous system at a rate that is different from the rate of 0.0340% :

Null hypothesis: $p=0.00034$

Alternative hypothesis: $p \neq 0.00034$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

3) Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.0003214 -0.00034}{\sqrt{\frac{0.00034(1-0.00034)}{420095}}}=-0.654$

4) Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level provided $\alpha=0.005$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(Z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.005$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can say that the true proportion not differs significantly from the specified value of 0.00034 or 0.034%.

4 0

3 years ago

Choose the graph of the function y = -tan 4x.

dalvyx [7]

Step-by-step explanation:

I have attached the graph of the question. So this is the graph of the question and i also attached the solved question screen shot.

I hope you get the idea. Thanks

6 0

3 years ago