Can someone please help me i dont know the answer.

Help me please I don't understand! 0

yawa3891 [41]

1. Right
2. I forgot how to do that
3. X is 45
4. Y is 45

5 0

4 years ago

Not prime number in 12n- 5

Alona [7]

Answer:

55

Step-by-step explanation:

12 x 5 = 60

60-5 = 55

55 is not prime

5 0

3 years ago

For a store contest, 4 out of every 65 people who vist the store will receive a free DVD. If 455 people vist the store, how many

stealth61 [152]

I used cross multiplication and got 28

4 0

3 years ago

A manufacturer of a new medication on the market for Alzheimer's disease makes a claim that the medication is effective in 65% o

NeX [460]

Answer:

$z=\frac{0.639 -0.65}{\sqrt{\frac{0.65(1-0.65)}{180}}}=-0.309$

$p_v =P(z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults with the medication was effective is not significantly less than 0.65

Step-by-step explanation:

Data given and notation

n=180 represent the random sample taken

X=115 represent the adults with the medication was effective

$\hat p=\frac{115}{180}=0.639$ estimated proportion of adults with the medication was effective

$p_o=0.65$ is the value that we want to test

$\alpha=0.05$ represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

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

Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that true proportion is less than 0.65.:

Null hypothesis: $p \geq 0.65$

Alternative hypothesis: $p < 0.65$

When we conduct a proportion test we need to use the z statisitc, 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 $p_o$ .

Calculate the statistic

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

$z=\frac{0.639 -0.65}{\sqrt{\frac{0.65(1-0.65)}{180}}}=-0.309$

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 $\alpha=0.05$ . The next step would be calculate the p value for this test.

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

$p_v =P(z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults with the medication was effective is not significantly less than 0.65

3 0

3 years ago

Find the quotient (line over 42 is repeating)

strojnjashka [21]

The correct answer is: [C]:  " $\frac{21}{11}$ " .
_____________________________________________________

<span>Explanation:
_____________________________________________________
</span>
Let us begin by converting the:
"0.42 (with the "repeating bar on the digits, "42") " ;

into a fraction, as follows:
______________________________________________________
Let x = 0.42424242424242424242424242424242....

100x = 42.42424242424242424242424242424242....
______________________________________________________

100x = 42.42424242424242424242424242424242....
– x = 0.42424242424242424242424242424242...
______________________________________________________
99x = 42.000000000000000000000000000000.... ;

→ 99x = 42 ;

Divide each side of the equation by " 99 " ;
to isolate "x" on one side of the equation; & to solve for "x" ;
______________________________________________________
→ 99x / 99 = 42/99 = (42 ÷ 3) / (99 ÷ 3) = 14/ 33;

→ x = " $\frac{14}{33}$ " .

So; "0.42 (with a repeating bar over the digits, "42" ;

is equal to: " $\frac{14}{33}$ "
________________________________________________
So, rewrite the question/problem being asked:
________________________________________________
"Find the quotient:
________________________________________________
$\frac{14}{33}$ ÷ $\frac{2}{9}$ ;

=   $\frac{14}{33}$ * $\frac{9}{2}$ ;

Note: The "14" cancels to a "7" <span>; and</span> the "2" cancels to a "1" ;
→ {since: " 14 ÷ 2 = 7 " ; and since: " 2 ÷ 2 = 1 "} ;

Note : The "33" cancels to an "11" ; and the "9" cancels to a "3" ;
   → {since: " 33 ÷ 3 = 11 " ; and since: " 9 ÷ 3 = 3 "} ;

And we can rewrite the problem as:
____________________________________________________

" $\frac{7}{11}$ * $\frac{3}{1}$ " ;

= $\frac{(7*3)}{(11*1}$ = $\frac{21}{11}$ ;

→ which is: Answer choice: [C]: " $\frac{21}{11}$ " .
____________________________________________________

3 0

4 years ago