To solve this question, the normal distribution and the central limit theorem are used.
Doing this, there is an 0.0129 = 1.29% probability that the mean installation time for 31 computers is less than 43 minutes.
------------------------------------
First, these concepts are presented, then we identify mean, standard deviation and sample size, and then, we find the desired probability.
------------------------------------
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
------------------------------------
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
------------------------------------
Mean of 45, standard deviation of 5:
This means that [tex]\mu = 45, \sigma = 5[/tex]
Sample size of 31:
This means that [tex]n = 31, s = \frac{5}{\sqrt{31}}[/tex]
------------------------------------
Probability the sample mean is less than 43:
This is the p-value of Z when X = 43, so:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{43 - 45}{\frac{5}{\sqrt{31}}}[/tex]
[tex]Z = -2.23[/tex]
[tex]Z = -2.23[/tex] has a p-value of 0.0129.
Thus, 0.0129 = 1.29% probability that the mean installation time for 31 computers is less than 43 minutes.
A similar question is given at: https://brainly.com/question/15020228
p=2,-3 and Q= -1,4. Evaluate 3q-2p
Answer:
When p=2 , q=-1
3q-2p
3(-1) - 2(2)
(3)-4
-1
When p=-3 , q=4
3(4)-2(-3)
(12 )-(-6)
=18
5. A Ferris wheel at an amusement park measures 16m in diameter. It makes 3 rotations
every minute. The bottom of the Ferris wheel is 1m above the ground. Riders board the
Ferris wheel at the minimum point.
a) Determine the equation that models Emily's height (m) with respect to time (in seconds)
above ground. [3A]
b) A 12m tree stands near the Ferris wheel. For how long (in seconds) is Emily higher than
the tree during the first rotation? Round to 2 decimal places. [4A]
Following are the responses to the given points:
For point a:
[tex]Diameter\ (d)= 16\ m\\\\[/tex]
Calculating the 3 rotations for every minute:
Calculating time for completing 1 rotation:
[tex]1\ rotation=\frac{60}{3}= 20\ second\\\\period=20 \ second\\\\[/tex]
The standard form of the equation of the sine and cosine function is:
[tex]y=A \sin \{ B(x-c)\} +D\\\\y=A \cos \{ B(x-c)\} +D\\\\[/tex]
Calculating the Amplitue:
[tex]A=\frac{max-min}{2}=\frac{17-1}{2}=\frac{16}{2}=8\\\\Period=\frac{2\pi}{B}\\\\20=\frac{2\pi}{B}\\\\B=\frac{2\pi}{20}\\\\B=\frac{\pi}{10}\\\\[/tex]
Calculating the phase shift:
for [tex]\sin[/tex] function: [tex]c=5[/tex]
for [tex]\cos[/tex] function: [tex]c=10[/tex]
Calculating the vertical shift:
[tex]\to D=\frac{max+ min }{2}=\frac{17+ 1}{2}=\frac{18}{2}=9\\\\y=8 \sin \{ \frac{\pi}{10}(t-5)\} +9\\\\y=8 \cos \{ \frac{\pi}{10}(t-10)\} +9\\\\[/tex]
For point b:
[tex]y> 12\ m\\\\12=8 \sin \{ \frac{\pi}{10}(t-5)\} +9\\\\12-9=8 \sin \{ \frac{\pi}{10}(t-5)\} \\\\3=8 \sin \{ \frac{\pi}{10}(t-5)\} \\\\\frac{3}{8}=\sin \{ \frac{\pi}{10}(t-5)\} \\\\\sin^{-1}\frac{3}{8}=\frac{\pi}{10}(t-5) \\\\\frac{\pi}{10} (0.38439677)=(t-5) \\\\1.22357+5=t \\\\t=6.22357\ second\\\\t=6.22\ second\\\\\sin^{-1}\frac{3}{8}=\frac{\pi}{10}(t-5) \\\\\frac{\pi}{10} (2.7571961)=(t-5) \\\\t=8.7764+5\\\\t=13.78\ second\\\\t_2-t_1=13.7764-6.22357= 7.55283\approx 7.55\ second \\\\[/tex]
Learn more:
Rotation: brainly.in/question/39626227
There are two independent file servers in a web site. Either file server works with a probability of 0.6. And this web site is up if either file server is working. The probability that the web site is up is _____.
Answer:
The probability that the web site is up is 0.84 = 84%.
Step-by-step explanation:
For each web server, there are only two possible outcomes. Either it is working, or it is not. The probability of a web server being working is independent of any other web server, which meas that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
Either file server works with a probability of 0.6.
This means that [tex]p = 0.6[/tex]
Two servers.
This means that [tex]n = 2[/tex]
The probability that the web site is up is
At least one server working, which is:
[tex]P(X \geq 1) = 1 - P(X = 0)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{2,0}.(0.6)^{0}.(0.4)^{2} = 0.16[/tex]
Then
[tex]P(X \geq 1) = 1 - P(X = 0) = 1 - 0.16 = 0.84[/tex]
The probability that the web site is up is 0.84 = 84%.
help plzz! find the value of x
Answer: 12°
Hope this helps!
PLEASE i need the answers!!!!!!!!!
I have no time please if you know the answer please tell MEEE!!!!!!!!!!!
Answer:
5x^2(2-3x)
(n+4)(x+y)
Step-by-step explanation:
How to do this please help
Answer:
[tex]\frac{1}{9}[/tex] feet³
Step-by-step explanation:
[tex]\frac{1}{3}[/tex]×[tex]\frac{2}{3}[/tex]×[tex]\frac{1}{2}[/tex]=[tex]\frac{2}{18}[/tex]=[tex]\frac{1}{9}[/tex]
Answer:
V = 1/9 ft^3
Step-by-step explanation:
The volume is given by
V = l*w*h where l = length, w = width, h = height
V = 1/3 * 2/3 * 1/2
V = 2/9*1/2
V = 1/9 ft^3
In the triangle shown below (not to scale), what is the angle gamma, y, when
A=6.8, B= 8.4, and C = 11.5? Answer in degrees rounded to at least
the nearest hundredth.
ILL GIVE YOU BRAINLIEST!
Answer:
γ = 97.77°
Step-by-step explanation:
A = 6.8
B = 8.4
C = 11.5
To find γ, apply the angle version of the Law of Cosines:
Cos γ = (A² + B² - C²)/(2AB)
Plug in the values
Cos γ = (6.8² + 8.4² - 11.5²)/(2*6.8*8.4)
Cos γ = -15.45/114.24
Cos γ = -0.1352
γ = Cos^{-1}(-0.1352)
γ = 97.77° (nearest hundredth)
what value of n make an equation??
Answer:
[tex]\frac{4}{27}[/tex]
Step-by-step explanation:
simplify the terms on both sides;
12*18*n=32
n*216=32
n=32/216
simplified --> 4/27
you can check by plugging it back into the equation;
12*n*3*6=4*8
12*(4/27)*3*6=32
216*(4/27)=32
32=32
Simplify 12w + 2 (w + 3)
Answer:
= 14w + 6
Step-by-step explanation:
= 12w + 2w + 6
Add similar elements: 12w + 2w = 14w
= 14w + 6
HELP ASAP!!!!!!!PLEASE SHOW WORK!!!!!!
Answer:
Area = 72.62 m²
Step-by-step explanation:
Area of a triangle with the given three sides is given by,
Area = [tex]\sqrt{s(s-a)(s-b)(s-c)}[/tex]
Here, s = [tex]\frac{a+b+c}{2}[/tex]
And a, b, c are the sides of the triangle.
From the question,
a = 20 m, b = 10 m and c = 15 m
s = [tex]\frac{20+10+15}{2}[/tex]
s = 22.5
Substitute these values in the formula,
Area = [tex]\sqrt{22.5(22.5-20)(22.5-10)(22.5-15)}[/tex]
= [tex]\sqrt{22.5(2.5)(12.5)(7.5)}[/tex]
= [tex]\sqrt{5273.4375}[/tex]
= 72.62 m²
A television stand at Wiles' Discount Mart is $187, and the sales tax is 6%. What is the amount of tax to be paid for the TV?
Answer:
$11.22
Step-by-step explanation:
100% = 187
1% = 187/100 = $1.87
6% = 1%×6 = 1.87×6 = $11.22
Answer:
In this case, you need to calculate the 6% of the price, which is 187 $.
We only need to multiply the price (187) by the percentage (6%):
187 * 0.06 = 11.22
So the tax would be $11.22
Help please Find the measure of the missing angles.
9514 1404 393
Answer:
x = 64°
y = 26°
Step-by-step explanation:
Angle x and 26° together make a right angle, so ...
x = 90° -26° = 64°
Angles x and y together make a right angle, so ...
y = 90° -(90° -26°) = 26°
A piece of art is in the shape of an equilateral triangle with sides of 7 inches each. Find the area of the piece of art to the nearest tenth. Explain how you know.
Answer:
21.2 in²
Step-by-step explanation:
The area of an equilateral triangle is given as :
Area, A = √3/4 * a²
Where, a = side length of the equilateral triangle
a = 7 inches ; Recall that all sides of an equilateral triangle are the same.
Put a = 7 in the equation :
A = √3/4 * a²
A = √3/4 * 7²
A = 0.4330127 * 49
A = 21.217 in²
Area, A = 21.2 in²
Please help!!!!!!!!!!!!
9514 1404 393
Answer:
(c) 16°
Step-by-step explanation:
The external angle at P is half the difference of the intercepted arcs:
P = (90° -58°)/2 = 32°/2
P = 16°
A. Two numbers are in the ratio 5:7. When 3 is added to each number, the new ratio becomes 3 : 4. Find the numbers.
Answer:
answer is 3 and ratio of two different numbers
help with plz thank you
Your answer is in the attachment..
Hope the answer helps you..
.
.
Select it as the BRAINLIEST..
Answer:
38. skipping by 3s
14, 17, 20, 23, 26, 29, 32, 35, 38
From a random sample of 20 bars selected at random from those produced, calculations gave a mean weight of = 52.46 grams and standard deviation of s = 0.42 grams. Assuming t distribution is followed, construct a 90% confidence interval for the mean weight of bars produced, giving the limits to two decimal places.
Answer:
(52.30 ; 52.62)
Step-by-step explanation:
Given :
Sample size, n = 20
Mean, xbar = 52.46
Standard deviation, s = 0.42
We assume a t - distribution
The 90% confidence interval
The confidence interval relation :
C.I = xbar ± Tcritical * s/√n
To obtain the Tcritical value :
Degree of freedom, df = n - 1 ; 20 - 1 = 19 ; α = (1 - 0.90) /2 = 0.1/2 = 0.05
Using the T-distribution table, Tcritical = 1.729
We now have :
C.I = 52.46 ± (1.729 * 0.42/√20)
C. I = 52.46 ± 0.1624
C.I = (52.30 ; 52.62)
A new restaurant sells cheeseburgers for 6$, french fries for 3$, and salads for 8$ On opening night, the restaurant sold items and made 1070$. They sold 4 times as many fries as salads. How many cheeseburgers were sold?
Answer:
25 cheeseburger
Step-by-step explanation:
I checked and get that 4 times fries as many as salad means that fries = 4 times Salad.
Brainliest please~
25 cheeseburgers were sold.
What is algebraic expression?In mathematics, an expression that incorporates variables, constants, and algebraic operations is known as an algebraic expression (addition, subtraction, etc.). Terms comprise expressions.
Let cheeseburger be x
Price of x = 6
Let French Fries be y
Price of y = 3
Let salads be z
Price of z=8
x+ y+ z =220
6x + 3y + 8z = 1070
4 y = z 4 times as many as
= 4 times - Fries is more than Salad
Substitute 3 in 1
x + 4 z + z =220
x+5z =220
Substitute 3 in 2
6x + 12z +8z = 1070
6x + 20z = 1070
3x + 10z - 535
From 4: x=220-5z
Substitute into 3 (220-5z) +10z = 535
660 - 15z+10z=535
- 5z = - 125
z = 25
To learn more about algebraic expressions refer to:
https://brainly.com/question/19864285
#SPJ2
PLEEASE HELP ME IM RUNNING LATE
If mC = 49 , find the values of x and y.
Answer:
m∠y=41
m∠x=90
Step-by-step explanation:
It is an isosceles triangle, so m∠B=49 too
49+49=98
180-98=82
82÷2=41
m∠y=41
41+49=90
180-90=90
m∠x=90
The birth rate of a population is b(t) = 2000e0.023t people per year and the death rate is d(t)= 1410e0.017t people per year, find the area between these curves for 0 ≤ t ≤ 10. (Round your answer to the nearest integer.) people
Answer: 7118
Step-by-step explanation:
Given
Birth rate is [tex]b(t)=2000e^{0.023t}[/tex]
Death rate is [tex]d(t)=1410e^{0.017t}[/tex]
Area between them is given by
[tex]\Rightarrow A=\int _0^{10}2000e^{0.023t}-1410e^{0.017t}dt\\\Rightarrow A=\int _0^{10}2000e^{0.023t}dt-\int _0^{10}1410e^{0.017t}dt\\\Rightarrow A=22486.95652 -15368.99999\\\Rightarrow A=7117.95652[/tex]
Thus, the area between the curves is [tex]7117.95652\approx 7118[/tex]
The global surface water area is 361, 132,000 square metres. Calculate the volume of water needed to cause a 3mm in sea level.
Answer:
The volume of water is 396 cubic meter.
Step-by-step explanation:
Area of water, A = 132000 square meter
Height, h = 3 mm = 0.003 m
The volume of water is given by
V = Area x height
V = 132000 x 0.003
V = 396 cubic meter.
Assume that thermometer readings are normally distributed with a mean of 0 degrees C and a standard deviation of 1.00 degrees C. A thermometer is randomly selected and tested. For the case below, draw a sketch, and find the probability of the reading. (The given values are in celsius degrees)
Between -1.42 and 1.61
The probability of getting a reading between -1.42 degrees C and 1.61 degreesC is_______ ( round to four decimal places as needed)
Answer:
The probability of getting a reading between -1.42 degree C and 1.61 degree C is 0.8685.
Step-by-step explanation:
We are given that
[tex]Mean,\mu=0[/tex] degree C
Standard deviation, [tex]\sigma=1[/tex] degree C
We have to find the probability of the reading between -1.42 and 1.61.
[tex]P(-1.42<x<1.61)=P(\frac{-1.42-0}{1}<\frac{x-\mu}{\sigma}<\frac{1.61-0}{1})[/tex]
[tex]P(-1.42<x<1.61)=P(-1.42<Z<1.61)[/tex]
[tex]P(-1.42<x<1.61)=P(Z<1.61)-P(Z<-1.42)[/tex]
Using the formula
[tex]P(a<z<b)=P(z<b)-P(z<a)[/tex]
[tex]P(-1.42<x<1.61)=0.94630-0.07780[/tex]
[tex]P(-1.42<x<1.61)=0.8685[/tex]
Hence, the probability of getting a reading between -1.42 degree C and 1.61 degree C is 0.8685.
Which ratio expresses the scale used to create this drawing?
1 square=10 yards
Answer:
option B
Step-by-step explanation:
option B
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PLEASE HELP WILL MARK BRAINLIEST
Using the table above, if the reserve requirement is 10%, then the additional amount the bank could loan out is
$40,000
$60,000
$300,000
$340,000
$1,800,000
Write down all the Subsets of {20,40}
Answer:
{20}, {40}, {20,40}, { }
Find X?
please help?
Look at one side of the triangle. It forms a right triangle with 45 degree angles.
A 45 degree triangle the base and height are the same, so the height would also be 26.
The hypotenuse(x) of a 45 degree right triangle is the side length time the sqrt(2)
The answer is: 26 sqrt(2)
make x the subject of the relaton3x-ax=2x+5
Answer:
x =5/ (1-a)
Step-by-step explanation:
3x-ax=2x+5
Subtract 2x from each side
3x -ax-2x = 2x+5-2x
3x -ax -2x = 5
combine like terms
x-ax = 5
Factor out x
x(1-a) =5
Divide each side by 1-a
x =5/ (1-a)
[tex]\boxed{\large{\bold{\textbf{\textsf{{\color{blue}{Answer}}}}}}:)}[/tex]
[tex]3x-ax=2x+5\\\\3x-ax-2x=5\\\\(3-2)x-ax=5\\\\x-ax=5\\\\x(1-a)=5\\\\\dashrightarrow x=\dfrac{5}{1-a}[/tex]
if √7-y=6, then y=
-29
-5
1
29
I don't know
Hello!
√7 - y = 6 <=>
<=> -y = 6 - √7 <=>
<=> y = -6 + √7 => √7 - (-6 + √7) = 6
Good luck! :)
Answer:
-29
Step-by-step explanation:
When you substitute 1 for y in the original equation, you get:
7−(1)−−−−−−√
=?
6
6–√
≠
6 So 1 is not a solution.
Someone help me pls !!!!!
Answer:
1)a
the problem asks"what PERCENT of 5 is 4?"
2)part
it gives both the percent and the whole, so your left with the part
3)Whole
4 is a part which is 80%
Step-by-step explanation:
A person can see the top of a building at an angle of 65°. The person is standing 50 ft away from
the building and has an eye level of 5 ft. How tall is the building to the nearest tenth of a foot?
O 107.2 ft
O 112.2 ft
O 50.3 ft
O 26.1 ft
9514 1404 393
Answer:
(b) 112.2 ft
Step-by-step explanation:
The relevant trig relation is ...
Tan = Opposite/Adjacent
For the given geometry, this becomes ...
tan(65°) = (height above eye level)/(50 ft)
Then we have ...
(height above eye level) = (50 ft)tan(65°) = 107.2 ft
Adding the height of eye level will give us the height of the building.
building height = (eye level height) + (height above eye level)
building height = (5 ft) + (107.2 ft)
building height = 112.2 ft
