1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MakcuM [25]
2 years ago
14

Help ASAP please ! Explain too

Mathematics
1 answer:
lilavasa [31]2 years ago
5 0

Answer:

r=4

Step-by-step explanation:

you basically have to create a proportion. .5/12 = x/96. then u cross multiply

You might be interested in
23. A certain type of gasoline is supposed to have a mean octane rating of at least 90. Suppose measurements are taken on of 5 r
Nostrana [21]

Answer:

a) p_v =P(Z          

b) Since p_v we can reject the null hypothesis at the significance level given. So based on this we can commit type of Error I.

Because Type I error " is the rejection of a true null hypothesis".

c) P(\bar X >90)=1-P(Z

1-P(Z

d) For this case we need a z score that accumulates 0.02 of the area on the right tail and 0.98 on the left tail and this value is z=2.054

And we can use this formula:

2.054=\frac{90-89}{\frac{0.8}{\sqrt{n}}}

And if we solve for n we got:

n = (\frac{2.054 *0.8}{1})^2=2.7 \approx 3

Step-by-step explanation:

Previous concepts  and data given  

The margin of error is the range of values below and above the sample statistic in a confidence interval.  

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".  

We can calculate the sample mean and deviation with the following formulas:

\bar X = \frac{\sum_{i=1}^n X_i}{n}

s=\sqrt{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}

\bar X=88.96 represent the sample mean    

s=1.011 represent the sample standard deviation  

n=5 represent the sample selected  

\alpha significance level    

State the null and alternative hypotheses.    

We need to conduct a hypothesis in order to check if the mean is less than 90, the system of hypothesis would be:    

Null hypothesis:\mu \geq 90    

Alternative hypothesis:\mu < 90    

If we analyze the size for the sample is < 30 and we don't know the population deviation so is better apply a t 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:    

z=\frac{88.96-90}{\frac{0.8}{\sqrt{5}}}=-2.907      

Part a

P-value  

First we need to calculate the degrees of freedom given by:

df=n-1=5-1 = 4

Then since is a left tailed test the p value would be:    

p_v =P(Z    

Part b

Since p_v we can reject the null hypothesis at the significance level given. So based on this we can commit type of Error I.

Because Type I error " is the rejection of a true null hypothesis".

Part c

We want this probability:

P(\bar X

The best way to solve this problem is using the normal standard distribution and the z score given by:

z=\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}}

If we apply this formula to our probability we got this:

P(\bar X >90)=1-P(Z

1-P(Z

Part d

For this case we need a z score that accumulates 0.02 of the area on the right tail and 0.98 on the left tail and this value is z=2.054

And we can use this formula:

2.054=\frac{90-89}{\frac{0.8}{\sqrt{n}}}

And if we solve for n we got:

n = (\frac{2.054 *0.8}{1})^2=2.7 \approx 3

7 0
3 years ago
Simplify by dividing (-5/8)÷(-3/4)​
Olenka [21]
Here pls give brainliest

8 0
2 years ago
Read 2 more answers
Write an equation in slope-intercept form that goes through the points (-3, -4) and (3,4).
Marat540 [252]

Answer:

Y = 4/3x + 0

Step-by-step explanation:

(-3,-4) and (3,4) can be plugged in to rise over run.

y 4 -(-4) = 8

x 3 - (-3) = 6

8/6 = 4/3

Plug into slope intercept form

4 = 4/3(3) + b

4 = 12/3 +b

4 = 4 +b

Subtract from both sides

0 = b

Y = 4/3x + 0

4 0
3 years ago
Write the equation in slope-intercept form ,of the line that passes through the given point and is parallel to the given line
Marrrta [24]
1/3x-1 I believe is the answer
5 0
2 years ago
Which statement regarding the interior and exterior angles of a triangle is always true?
faust18 [17]

A: an exterior angle is supplementary to the adjacent interior angle.

3 0
3 years ago
Read 2 more answers
Other questions:
  • In​ March, a family starts saving for a vacation they are planning for the end of August. The family expects the vacation to cos
    12·1 answer
  • If 3x - 1 = 11, what is the value of x2 + x?
    5·1 answer
  • 18 + X over 4 = 7<br><br> What is X?
    5·1 answer
  • In a science test, Jamie solved 42 correct and 18 incorrect answers. What is the percentage of correct question?
    13·2 answers
  • Which is bigger 0.07 or 0.005?
    7·1 answer
  • Direct Variation: If y = -16, when x = 4, find x when y = -96.
    7·1 answer
  • Caleb strung a 12 foot rope from the bottom of one fence post to the top of another. He measured the angle of elevation of the r
    9·1 answer
  • A Jorge le otorgaron una beca de $60.000 por sus buenas calificaciones y escasos recursos. Si gasta cada me la 2\5 partes de la
    14·1 answer
  • NEED HELP!!! BRAINLIEST!!!
    13·2 answers
  • A 13 meter long cylinder with a diameter of 8 meters has a square prism with a base length of 3 meters hole going all the way th
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!