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2 years ago

05.02 LC)

Mathematics

1 answer:

nikklg [1K]2 years ago

8 0

Answer:

x = 30

Step-by-step explanation:

30 + 2x = 90

2x = 60

x = 30

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Emissions of sulfur dioxide by industry sett off chemical changes in the atmosphere that result in "acid rain". The acidity of l

horsena [70]

Answer:

Case n =5

$z=\frac{4.8-5}{\frac{0.5}{\sqrt{5}}}=-0.894$

Case n =15

$z=\frac{4.8-5}{\frac{0.5}{\sqrt{15}}}=-1.549$

Case n = 40

$z=\frac{4.8-5}{\frac{0.5}{\sqrt{40}}}=-2.530$

P value

Case n =5

$p_v =P(z$

Case n =15

$p_v =P(z$

Case n =40

$p_v =P(z$

Step-by-step explanation:

Data given and notation

$\bar X=4.8$ represent the sample mean

$\sigma=0.5$ represent the population standard deviation

$n$ sample size

$\mu_o =5$ represent the value that we want to test

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

z 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 lower than 5, the system of hypothesis would be:

Null hypothesis: $\mu \geq 5$

Alternative hypothesis: $\mu < 5$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-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:

Case n =5

$z=\frac{4.8-5}{\frac{0.5}{\sqrt{5}}}=-0.894$

Case n =15

$z=\frac{4.8-5}{\frac{0.5}{\sqrt{15}}}=-1.549$

Case n = 40

$z=\frac{4.8-5}{\frac{0.5}{\sqrt{40}}}=-2.530$

P-value

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

Case n =5

$p_v =P(z$

Case n =15

$p_v =P(z$

Case n =40

$p_v =P(z$

5 0

3 years ago

A random sample of adults were asked whether they prefer reading an e-book over a printed book. The survey resulted in a sample

djyliett [7]

Answer: $(0.10\ ,\ 0.18)$

Step-by-step explanation:

According to the empirical rule, the 95% confidence interval for the true population proportion is given by :-

$(p'-2\sigma_{p'}\ ,\ p'+2\sigma_{p'})$

Given : . The survey resulted in a sample proportion of p′=0.14, with a sampling standard deviation of σp′=0.02, who preferred reading an e-book.

Then, the 95% confidence interval for the true proportion of adults who prefer e-books will be :-

$(0.14-2(0.02)\ ,\ 0.14+2(0.02))\\\\=(0.14-0.04\ ,\ 0.14+0.04)\\\\=(0.10\ ,\ 0.18)$

Hence, the 95% confidence interval for the true proportion of adults who prefer e-books= $(0.10\ ,\ 0.18)$

8 0

2 years ago

Simplify this radical 3√12 and this one 2√(48x^3 )

MakcuM [25]

For number one you should get 6√3

4 0

2 years ago

15.5 rounded to the nearest tenth

Degger [83]

The tenths place is to the right of the decimal point.
In order to round u number to the nearest tenth, you should to the right of the tenths place. Depending on this number you should determine if you will round up or stay the same (if it is bigger than 5 you will round up, if not it will stay the same).
In our case, the number is 15.5 so it is already rounded to the nearest tenth.

3 0

3 years ago

Please answer this question

VashaNatasha [74]

Answer:

i think 1

remember like this: y=mx+b

m is slope

b is y intercept

8 0

3 years ago

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