How do you find x in the equation 3x+21=42 Plz help will mark brianltes

A company that produces laundry detergent is interested in the level of consumer awareness concerning the unique properties of t

Veseljchak [2.6K]

Answer:

The value of test statistic is -2.736.

The type of alternate hypothesis is Left- tailed.

Step-by-step explanation:

We are given that Historical data indicated that among the consumers who buy this detergent, the proportion who purchased it because they had seen it advertised on TV is 0.80. In a random sample of 400 consumers who bought this detergent, 296 indicated that they bought it because they saw it advertised on TV.

We have to test the hypothesis to determine if there is sufficient evidence to conclude that the population proportion is less than 0.80.

Let p = population proportion of people who purchased the detergent because they had seen it advertised on TV.

SO, Null Hypothesis, $H_0$ : p $\geq$ 0.80 {means that the population proportion of people who purchased the detergent because they had seen it advertised on TV is greater than or equal to 0.80}

Alternate Hypothesis, $H_a$ : p < 0.80 {means that the population proportion of people who purchased the detergent because they had seen it advertised on TV is less than 0.80}

The test statistics that will be used here is One-sample z-proportion test;

T.S. = $\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ~ N(0,1)

where, $\hat p$ = proportion of people who bought detergent because they saw it advertised on TV in a sample of 400 customers = $\frac{296}{400}$ = 0.74

n = sample of customers = 400

SO, test statistics = $\frac{0.74-0.80}{\sqrt{\frac{0.74(1-0.74)}{400} } }$

= -2.736

Therefore, the value of the test statistic for the test described above is -2.736.

And the type of alternative hypothesis is left-tailed because we have to determine whether the population proportion of people who purchased the detergent because they had seen it advertised on TV is less than 0.80.

8 0

3 years ago

In the past decades there have been intensive antismoking campaigns sponsored by both federal and private agencies. In one study

DIA [1.3K]

Answer:

$z=\frac{0.384-0.362}{\sqrt{0.374(1-0.374)(\frac{1}{4276}+\frac{1}{3908})}}=2.055$

The p value can be calculated from the alternative hypothesis with this probability:

$p_v =2*P(Z>2.055)=0.0399$

And the best option for this case would be:

C. between 0.01 and 0.05.

Step-by-step explanation:

Information provided

$X_{1}=1642$ represent the number of smokers from the sample in 1995

$X_{2}=1415$ represent the number of smokers from the sample in 2010

$n_{1}=4276$ sample from 1995

$n_{2}=3908$ sample from 2010

$p_{1}=\frac{1642}{4276}=0.384$ represent the proportion of smokers from the sample in 1995

$p_{2}=\frac{1415}{3908}=0.362$ represent the proportion of smokers from the sample in 2010

$\hat p$ represent the pooled estimate of p

z would represent the statistic

$p_v$ represent the value for the pvalue

System of hypothesis

We want to test the equality of the proportion of smokers and the system of hypothesis are:

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

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

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 $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{1642+1415}{4276+3908}=0.374$

Replacing the info given we got:

$z=\frac{0.384-0.362}{\sqrt{0.374(1-0.374)(\frac{1}{4276}+\frac{1}{3908})}}=2.055$

The p value can be calculated from the alternative hypothesis with this probability:

$p_v =2*P(Z>2.055)=0.0399$

And the best option for this case would be:

C. between 0.01 and 0.05.

7 0

3 years ago

Create a system of quadratic inequalities. Graph the system and list three values in their solution set. Show your work.

givi [52]

Uhhhhhhhhhhhhhhhhhhhhhhh

4 0

3 years ago

Need help with this problem

Alika [10]

Answer: B) 86°

Step-by-step explanation:

The angles of a triangle always add to equal 180.

So let's call the third angle x and add the other two angles with it.

32+62+x=180

94+x=180

Now we solve for x

Subtract 94 from both sides

94-94+x=180=94

x=86

3 0

3 years ago

Can someone please help me!!! 2. A.86 B.152 C.43 D.92

prisoha [69]

Hi there,

the answer to this is 55°.

The reason it is 55° is because look at where the angel is <P. You can see that yes it is in the circle but it is located close to angle <C and <D and it's all connected to 55°

so that is your answer

Hope that is correct

Have a great day

5 0

4 years ago