Solve this system of equations by
using the elimination method.
4x - 7y = 2
- 8x + 7y = -18
Carson's tablet has 2,000 videos. The play time for the videos is skewed to the right, with a mean of 135 seconds and a standard deviation of 25 seconds.
Part A: Can you accurately calculate the probability that the mean play time is more than 142 seconds for an SRS of 10 videos? Explain. (4 points)
Part B: If you take a random sample of 50 videos instead of 10, explain how the Central Limit Theorem allows you to find the probability that the mean play time is more than 142 seconds. Calculate this probability and show your work. (6 points)
Answer:
SEE BELOW
Step-by-step explanation:
A: Yes, it is 18.80%. Sample Mean= 135, Sample Standard deviation= 25/sq rt of 10 = 7.906, normalcdf(142, 999999, 135, 7.906) = .18796 × 100 = 18.796 = 18.80%
B: If we increase the sample size to 50, then, due to the Central Limit Therme, there should be less variation within the data (it should point to a more clear center). Sample Mean= 135, Sample Standard deviation= 25/sq rt of 50 = 3.535, normalcdf(142, 999999, 135, 3.535) = .02385 × 100 = 2.385 = 2.39%
The probability that the mean playtime is more than 142 seconds for an SRS of 10 videos is not accurately calculated and the probability that the mean playtime is more than 142 seconds is 0.0244.
Given :
The total number of videos on Carson's tablet is 2000.The mean is 135 seconds.The standard deviation is 25 seconds.A) The probability that the mean playtime is more than 142 seconds for an SRS of 10 videos is not accurately calculated because the sample size is too small due to which the central limit theorem cannot be applied.
B) According to the given data, the sample size is 50.
[tex]P(\bar{X}>142)=P\left(\dfrac{\bar{X}-\mu}{\dfrac{\sigma}{\sqrt{n} }}>\dfrac{142-\mu}{\dfrac{\sigma}{\sqrt{n} }}\right)[/tex]
[tex]P(\bar{X}>142)=P\left(Z>\dfrac{142-135}{\dfrac{25}{\sqrt{50} }}\right)[/tex]
[tex]P(\bar{X}>142)=P\left(Z>1.9798\right)[/tex]
Using the z table the above expression becomes:
[tex]P(\bar{X}>142)=0.0244[/tex]
For more information, refer to the link given below:
https://brainly.com/question/898534
PLEASE HELP MEEEEEEEEEEE
15.
(01.03 LC)
What is 0.453 rounded to the nearest tenth?
0.5
0.45
0.44
0.4
19. What is the diameter of circle C?
Сл
3
A. 234
B. 34
C. 4
D. 8
Answer:
8
Step-by-step explanation:
in right angle triangle
h^2=p^2+b^2
5^2=3^2+b^2
25-9=b^2
b=√16=4
radius=4
diameter=4×2=8
Help pls :,)
Rosa made a mosaic wall mural using 40 black tiles, 33 blue tiles and 27 red tiles.
Enter a percent to represent the number of red tiles in the Mural.
The number of red tiles in the mural represents ??? %
Answer:
First you have to figure out the total.
42+35+23= 100
So plug it in.
23/100
23%
Your answer is 23%.
Hope this helped ^-^
Step-by-step explanation:
Factor using GCF.
Show your work!
1) 36a + 18b - 27c
f(x) = 3(3x + 4)
The inverse
Answer:
Step-by-step explanation:
find the inverse of the function y=9x+12
To find the inverse function, swap x and y, and solve the resulting equation for x.
If the initial function is not one-to-one, then there will be more than one inverse.
So, swap the variables: y=9x+12 becomes x=9y+12.
Now, solve the equation x=9y+12 for y.
[tex]f^{-1}[/tex](x) = (x-12)/9
y=(x−12)/9
state the collision theory
Answer:
Collision theory, theory used to predict the rates of chemical reactions, particularly for gases. The collision theory is based on the assumption that for a reaction to occur it is necessary for the reacting species (atoms or molecules) to come together or collide with one another.
Find A ∩ (BC). A = {2, 3, 5, 8} B = {3, 5, 7} C = {2, 4, 8}
Answer:
A/5%=b-c+3-5%=d£&68+7-7'
What quadrant is (6, −7) in? Quadrant I Quadrant II Quadrant III Quadrant IV
Answer:
(6,-7) Would be in Quadrant IV
Step-by-step explanation:
what goes into 27 and 48?
Answer:
Step-by-step explanation:
lets see
27=7*4=7*2*2
48=3*2*2*2*2
both numbers are divisible by 4
27/3=9, 48/3=16
Answer = 3
ILL MARK BRAINLIST , pls help n
Answer:
33
Step-by-step explanation:
[tex] {x}^{2} - 5x - 2 = 0 \\ \\ equating \: it \: with \\ a {x}^{2} + bx + c = 0 \\ we \: find : \\ a = 1 \\ b = - 5 \\ c = - 2 \\ \\ {b}^{2} - 4ac \\ = {( - 5)}^{2} - 4 \times 1( - 2) \\ = 25 + 8 \\ = 33 \\ \\ by \: quadratic \: formula \\ \\ x = \frac{ - b \pm \sqrt{ {b}^{2} -4ac } }{2a} \\ \\ x = \frac{ - ( - 5) \pm \sqrt{33}}{2 \times 1} \\ \\ x = \frac{ 5 \pm \sqrt{33}}{2}...(1) \\ \\x = \frac{ 5 \pm \sqrt{n}}{2}...(2) (given)\\ \\ equating \: equations \: (1) \: and \: (2) \\ \\ \huge \red{ \boxed{n = 33}}[/tex]
Please help me with this question! <3
Which set of coordinate pairs does NOT represent a linear function?
A.(−4, −12), (−3, −10), (−2, −8), (−1, −6)
B.(−4, −17), (−3, −10), (−2, 5), (−1, 2)
C.(1, −7), (2, −10), (3, −13), (4, −16)
D.(1, 1), (2, 4), (3, 7), (4, 10)
Answer:
c
Step-by-step explanation:
Two sides of an obtuse triangle measure 12 inches and 14 inches. The longest side measures 14 inches.
What is the greatest possible whole-number length of the unknown side?
ILL MARK BRAINLIST , pls help n
Answer:
answer is b
Step-by-step explanation:
Annual starting salaries for college graduates is unknown. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. If the population standard deviation is $3,750 how large should the sample be if margin of error is $500
Answer:
A sample of 217 is needed.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1-0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.025 = 0.975[/tex], so [tex]z = 1.96[/tex]
Now, find the margin of error M as such
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
If the population standard deviation is $3,750 how large should the sample be if margin of error is $500
We have that [tex]\sigma = 3750[/tex].
We need a sample of n, and n is found when [tex]M = 500[/tex]. So
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
[tex]500 = 1.96*\frac{3750}{\sqrt{n}}[/tex]
[tex]500\sqrt{n} = 1.96*3750[/tex]
[tex]\sqrt{n} = \frac{1.96*3750}{500}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.96*3750}{500})^{2}[/tex]
[tex]n = 216.1[/tex]
Rounding up
A sample of 217 is needed.
If g(x)= x+1/X-2
and h(x) = 4 – x, what is the value of (gºf)(-3) ?
a. 8/5
b. 5/2
c. 15/2
d. 18/5
helpppppppppppppppppppppp
Answer:
45 feet
Step-by-step explanation:
The percent of Tom’s budget he spends on different types of expenses is shown in the circle graph below. Tom’s total monthly budget is $2,500.
Tom's Expenses
Rent 30%
Savings 30%
Groceries 25%
Other 15%
How much does Tom spend each month on rent?
Answer:
$750
Step-by-step explanation:
rent is 30% of $2,500 Tom's total monthly budget.
30/100 x 2500 = 750
A diver is 25 feet below sea level. An airplane is 1,000 feet above sea level. What is the distance between the diver and the airplane?
Answer:
1025 Please Mark Me Brainliest
Step-by-step explanation:
What sets of numbers does the square root of 3 belong to?
Answer:
irrational
Step-by-step explanation:
its a decimal that never ends or repeats and cant be accurately turned into a fraction, like pi
Jorge can travel 50 miles on his
motorized scooter using 1 gallon of gas.
How many miles can he travel using
8 gallons of gas?
Answer:
its c
Step-by-step explanation:
Answer:
400 miles
Step-by-step explanation:
50 miles.....1 gallon
x miles......8 gallons
50*8=400
WILL GIVE BRAINLIEST!!!
Answer:
QR=11
Step-by-step explanation:
what is the approximate volume of this cylinder
Answer:
where is the cylinder.....................
Answer:
Where is the cylinder??????
Step-by-step explanation:
what is the square root of 724
Answer:26.9072480941
Step-by-step explanation:
write a word problem whose solution is $111
Answer:
Step-by-step explanation:
Word problem is a topic in mathematics that involves the interpretation of a given question with a mathematical expression so as to determine the value of the required variable.
Example: The price of a pencil is $10, and that of a ruler is $15.25. If Charles bought 5 pencils and 4 rulers, calculate the total amount of money spent.
price of a pencil = $10
price of a ruler = $15.25
Then,
cost of 5 pencils = $10 x 5
= $50
cost of 4 rulers = $15.25 x 4
= $61
Total amount of money spent by Charles = $50 + $61
= $111
The total amount of money spent by Charles is $111.
what is 30% of 180 show work
Answer:
30%=30/100=3/10
Step-by-step explanation:
3/10*180
Simplify 180 and 10.
3*18=54
hi please help urgent question!!!
will give brainlist :>
Answer:
dont know sos
Step-by-step explanation:
what is a eqvilent fraction to 6/20
Answer:
310 is equivalent to 620 because 3 x 20 = 10 x 6 = 60. 930 is equivalent to 620 because 9 x 20 = 30 x 6 = 180. 1240 is equivalent to 620 because 12 x 20 = 40 x 6 = 240.
Step-by-step explanation:
Answer:
30%
Step-by-step explanation:
What's 6 divided by 20?
6/20 = 30