Answer:
x=41/4
Step-by-step explanation:
According to the Secant Theorem, a(a+b)=c(c+d)
Therefore, 3(3+4x+12)=2(2+8x), 12x+45=16x+4, x=41/4
Suppose that attendance at the concerts by the band "Keane" is a normally distributed random variable X with a mean of 18,500. You are told that P(X ≥ 15,000) = 0.6981. What are the two values of X that delineate the "82% middle pack" of this random variable?
A random variable has a population mean equal to 1,973 and population variance equal to 892,021. Your interest lies in estimating the population mean of this random variable. With that in mind, you take a representative sample of size 79 from the population of the random variable. You then use this sample data to calculate the sample average as an estimate for the population mean.
Required:
Using your knowledge about the central limit theorem (CLT), and assuming that the CLT has already "established itself" / "kicked in" when the sample size is 79, what is the probability that the sample average that you calculated will lie between 1,702 and 1,948?
Answer:
The two values of X that delineate the "82% middle pack" of this random variable are 9480 and 27520.
0.4017 = 40.17% probability that the sample average that you calculated will lie between 1,702 and 1,948.
Step-by-step explanation:
To solve the first question, we use the normal distribution, while for the second quetion, it is used with the central limit theorem.
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 [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
First question:
Mean of 18,500:
This means that [tex]\mu = 18500[/tex]
You are told that P(X ≥ 15,000) = 0.6981.
This means that when [tex]X = 15000[/tex], Z has a o-value of 1 - 0.6981 = 0.3019, which means that when [tex]X = 15000, Z = -0.52[/tex]. We use this to find [tex]\sigma[/tex]. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-0.52 = \frac{15000 - 18500}{\sigma}[/tex]
[tex]0.52\sigma = 3500[/tex]
[tex]\sigma = \frac{3500}{0.52}[/tex]
[tex]\sigma = 6731[/tex]
What are the two values of X that delineate the "82% middle pack" of this random variable?
Between the 50 - (82/2) = 9th percentile and the 50 + (82/2) = 91st percentile.
9th percentile:
X when Z has a p-value of 0.09, so X when Z = -1.34.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.34 = \frac{X - 18500}{6731}[/tex]
[tex]X - 18500 = -1.34*6731[/tex]
[tex]X = 9480[/tex]
91st percentile:
X when Z has a p-value of 0.91, so X when Z = 1.34.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]1.34 = \frac{X - 18500}{6731}[/tex]
[tex]X - 18500 = 1.34*6731[/tex]
[tex]X = 27520[/tex]
The two values of X that delineate the "82% middle pack" of this random variable are 9480 and 27520.
Question 2:
A random variable has a population mean equal to 1,973 and population variance equal to 892,021.
This means that [tex]\mu = 1973, \sigma = \sqrt{892021} = 944.5[/tex]
Sample of 79:
This means that [tex]n = 79, s = \frac{944.5}{\sqrt{79}}[/tex]
What is the probability that the sample average that you calculated will lie between 1,702 and 1,948?
This is the p-value of Z when X = 1948 subtracted by the p-value of Z when X = 1702. So
X = 1948
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{1948 - 1973}{\frac{944.5}{\sqrt{79}}}[/tex]
[tex]Z = -0.235[/tex]
[tex]Z = -0.235[/tex] has a p-value of 0.4071
X = 1702
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{1702 - 1973}{\frac{944.5}{\sqrt{79}}}[/tex]
[tex]Z = -2.55[/tex]
[tex]Z = -2.55[/tex] has a p-value of 0.0054
0.4071 - 0.0054 = 0.4017
0.4017 = 40.17% probability that the sample average that you calculated will lie between 1,702 and 1,948.
Kyle works at a donut factory, where a 10-oz cup of coffee costs 95¢, a 14-oz cup costs $1.15, and a 20-oz cup costs $1.50. During one busy period, Kyle served 29 cups of coffee, using 444 ounces of coffee, while collecting a total of $35.90. How many cups of each size did Kyle fill?
Kyle filled ___ 10-oz cup(s), ___ 14-oz cup(s), and ___ 20-oz cup(s).
Answer:
10 oz: 7
14 oz: 8
20 oz: 6
Answer:
Kyle filled 4 servings of 10oz 16 servings of 14 oz 9 servings of 20 oz
Step-by-step explanation:
10oz 95c = x
14oz 1.15c = y
20oz 1.50c = z
444 given divided by 29 cups
= 444/29 = 15.3103448 average cup weight so the higher size were used more.
9 servings of 20 oz cups = 180 = cost check at 1.50 x 9 = $13.50
16 servings of 14 oz cups = 224 = cost check at 16 x 1.15 = $18.40
4 servings of 10 oz cups = 40 = cost check at 4 x 0.95 = $3.80
Where given collection total said to be $35.90 we total 13.5+18.4+3.8 = 35.7 so we are 0.20 out and can try again.
OR just submit this. 4 servings of 10oz 16 servings of 14 oz 9 servings of 20 oz
help me find the answer
Explain how to find the inverse of a Log Function. (Algebraically)
Answer:
Your welcome! :)
Step-by-step explanation:
To find the inverse of a function, we use the following steps:
1. Replace f(x) with y.
2. Interchange x and y.
3. Solve for y.
4. Replace y with f -1 (x).
Amanda buys a 1.5 litre carton of orange juice.
She has a number of plastic cups.
Each plastic cup holds 40 ml when full.
How many cups can Amanda completely fill with orange juice?
Answer:
Amanda can fill 37.5 cups
Step-by-step explanation:
Find an expression which represents the difference when (-4x – 3y) is subtracted
from (-2x – 10y) in simplest terms.
Answer: (-2x-10y)-(-4x-3y)
-2x-10y-(-4x-3y)
-2x-10y+4x+3y
-2x+4x-10y+3y
-2x+4x-10y+3
Answer =2x-7y
Step-by-step explanation:
Whats the nth term in this sequence
1 , 7, 13, 19
Step-by-step explanation:
the answer is in the above image
i need to find the area. please help
Answer:
A = 190 inches^2
Step-by-step explanation:
The total area would be area for a rectangle + half the area of a circle:
Area for a rectangle:
A = l x w
A = 12 x 15
A = 180 [tex]inches^{2}[/tex]
Area for half of the circle:
A = [tex]\frac{\pi r^{2} }{2}[/tex]
[tex]A = \frac{\pi 2.5^{2} }{2} \\\\= \frac{19.63}{2} \\\\= 9.8 inches^{2}[/tex]
Total area: Rectangle area + half of the circle area
= 180 + 9.8 = 189.8 = 190 inches^2
Step-by-step explanation:
Find the rectangle area first by using the formula A=length * width then find the semicircle area by using the formula A=pi*r²/2
Which expression represents the length, in inches,
of the framed picture?
Answer:
No solution is posible from the information provided
Step-by-step explanation:
Answer:
1. B
2. C
3. 8, 36
50% of a number is 32
what is the number
Answer:
64
Step-by-step explanation:
Half (50%) of 64 would be 32
Answer:
64
Step-by-step explanation:
let the number be x
according to the question ,
50 % of x = 32
50/100 * x = 32
50x = 32 *100
x = 3200/50
x = 64
therefore a number is 64
Suppose X is a random variable with a mean of 10 and a variance of 100. Suppose Y is a random variable with a mean of 2 and a standard deviation of 16. Also, suppose X and Y are independent. What is the mean of 10 X + 3 Y?
Answer:
[tex]E(10x + 3y) =106[/tex]
Step-by-step explanation:
Given
[tex]E(x) =10[/tex]
[tex]Var(x) = 100[/tex]
[tex]E(y) =2[/tex]
[tex]Var(y) = 16[/tex]
Required
[tex]E(10x + 3y)[/tex]
To do this, we make use of the following equation
[tex]E(ax + by) =aE(x) + bE(y)[/tex]
So, we have:
[tex]E(10x + 3y) =10 * E(x) + 3 *E(y)[/tex]
[tex]E(10x + 3y) =10 * 10 + 3 *2[/tex]
[tex]E(10x + 3y) =100 + 6[/tex]
[tex]E(10x + 3y) =106[/tex]
What is the value of n?
Answer:
A
Step-by-step explanation:
180-133= 47
180-142= 38
47+38= 85
180-85= 95
If the inside of n is 95, n has to be 85
please help me simplify the expression and please show work!!! <3
Step-by-step explanation:
[tex] \frac{x + 4}{3 {x}^{2} - 12x - 96} = \frac{x + 4}{3( {x}^{2} - 4x - 32) } = \frac{x + 4}{3(x - 8)(x + 4)} [/tex]
[tex] = \frac{1}{3(x - 8)} = \frac{1}{3x - 24} [/tex]
The difference of two numbers is 13. The sum of two numbers is 75
Answer:
The numbers are 31 and 44.
Step-by-step explanation:
Given that the difference of two numbers is 13, and the sum of two numbers is 75, to determine what these numbers are, the following calculations must be performed:
(75 - 13) / 2 = X
62/2 = X
31 = X
31 + (31 + 13) = X
31 + 44 = X
75 = X
Therefore, the numbers are 31 and 44.
Select the correct answer from each drop-down menu.
What is the end behavior of function h?
h(x) = -4x2 + 11
As x approaches negative infinity, h(x) approaches
As x approaches positive infinity, h(x) approaches
Answer:
The first is negative and the second is also negative. Just took the test and passed.
Step-by-step explanation: Step by Step
Because the variable has an even power, we will see that:
As x approaches -∞, h(x) approaches -∞As x approaches ∞, h(x) approaches -∞.What is the end behavior of h(x)?Here we have h(x) = -4x^2 + 11
Notice that the variable is squared, this means that the sign does not matter, the outcome of:
-4x^2 will always be negative. So in both ends (when x tends to infinity and negative infinity), we will have the same end behavior.
When we take that limit, -4x^2 will just tend to negative infinity, then in both cases, the function tends to negative infinity.
So we have:
As x approaches negative infinity, h(x) approaches negative infinity.As x approaches positive infinity, h(x) approaches negative infinity.If you want to learn more about limits, you can read:
https://brainly.com/question/5313449
which expression is equivalent to 6 + 3 * 4 - 1 / 3
Answer:
12 2/3
Step-by-step explanation:
add the integers to get 6+3 + 4 = 13
Now subtract 1/3
13 = 12 + 1 - 1/3
but one is equal to 3/3
12 + 3/3 - 1/3
12 2/3
Plzzz answer I don’t have a lot of time
Answer:
p=35
Step-by-step explanation:
2p+5+3p =180 degree (being linear pair)
5p+5=180
5p=180-5
p=175/5
p=35
A linear pair is a pair of adjacent angles formed when two lines intersect.
What is the slope of the line graphed below?
(-2,2)
(3, 1)
Answer:
hey. your questions is not complete. pls add an attachment of the graph to your question
Answer:
[tex]-\frac{1}{5}[/tex]
Step-by-step explanation:
To find the slope, the formula is [tex]\frac{y2-y1}{x2-x1}[/tex]
[tex]\frac{1-2}{3-(-2)}=-\frac{1}{5}[/tex]
Hope this helps
Samuel made a list of his test scores: 88, 100, 92, 80, 85, 94, and 90. What is the lowest test score he can get on his next test to have mean score of 90?
Answer:
he needs to get a 91 to have a mean score of 90
Step-by-step explanation:
add up all the known scores to get 629
let 's' = lowest test score
(629 + s) ÷ 8 = 90 [we divide by 8 because there are 7 known and 1 unknown score)
cross-multiply to get:
629 + s = 720
s = 720-629
s = 91
Maria is asked to write down a prime number between 10 and 20 she writes down 17 is she right explain your answer
Answer:
YES
Step-by-step explanation:
PRIME NUMBER BETWEEN 10 & 20 ARE 11,13,17,19-four
Step-by-step explanation:
it has no factor excluding 1 and itself
Ariel has a plastic ice cream cone in her food playset. The ice cream cone is a half-sphere sitting on top of a cone. What is the
approximate volume of the toy ice cream cone? Use 3.14 for x.
52 Step-by-step explanation:
basic triangle proofs
please help
Answer:
Step-by-step explanation:
Hope this helps u !!!
I need the answer find the value of x
Answer:
1. x = 126
angle POS = 33
2. x = 31
angle MOL = 118
Step-by-step explanation:
for question one, 147 degrees equals x + 21
so x = 126
147 plus 147 equals 294
360-294 equals 66
66/2 equals angle POS
angle POS = 33
for question 2, 62 degrees equals 2x
62 divided by 2 is 31
x = 31
62 + 62 = 124
360-124 = 236
236/2 = 118
angle MOL = 118
Answer:76
Step-by-step explanation:
67
The_____ is the result of the sum of the numbers being divided by how many numbers are in set.
Answer:
Mean
Step-by-step explanation:
Mean
less precisely called the average
11. Choose the proportion that represents this problem:
If one meter is approximately 3.28 ft, how many meters are
in 20 ft?
a) 3.28
20
b) 3.28
20
1
1
m
O ) c) 3.28
20
1
d) 20
3.28
1
m
т
Answer:
D is the answer
Step-by-step explanation:
Which of the following best shows the distributive property?
1. 2(2 - 3) = 2(-1)
2. 2(2 - 3) = 2(2) - 2(3)
3. 2 - 3 = (-3) + 2
4. 2 + (2 - 3) = (2 - 2) + 3
Answer:
number 2
Step-by-step explanation:
2x2=4
2x-3=-6
4-6=-2
2x2=4
-2x3=-6
4-6=-2
A machine depreciate in value at the rate of 10% every year on reducing balance. if the original cost is 20000 and the scrapped value is 13122, how long has the equipment been used?
ratios that are equivalent to 7/6
Answer:
14 : 12 , 21 : 18 and 28 : 24 .
Step-by-step explanation:
Answer:
14 : 12 , 21 : 18 and 28 : 24 .
Step-by-step explanation:
Therefore, 14 : 12 , 21 : 18 and 28 : 24
What is the value of the expression shown below?
Answer:
23 1/4
Step-by-step explanation:
3/6 ^ 2 = 1/4
7 * 4 = 28
28 + 1/4 = 113/4
113/4 - 5 = 93/4
93/4 = 23 1/4
Suppose the linear regression line V 4.009x - 77.531 predicts a pizza a
parlor's profits based on the number of pizzas sold. If x represents the
number of pizzas sold, and V represents the pizza parlor's profits in dollars,
about how much can the pizza parlor expect in profits if it sells 325 pizzas?
Answer:
$1225.39
Step-by-step explanation: