Answer:
She would spend $52.50.
Step-by-step explanation:
c = 3.5t
c = 3.5(15)
c = $52.50
Hope this helped! :)
Answer:
328.48
Step-by-step explanation:
The width of a casing for a door is normally distributed with a mean of 24 inches and a standard deviation of 1/8 inch. The width of a door is normally distributed with a mean of 23 7/8 inches and a standard deviation of 1/16 inch. Assume independence. a. Determine the mean and standard deviation of the difference between the width of the casing and the width of the door. b. What is the probability that the width of the casing minus the width of the door exceeds 1/4 inch? c. What is the probability that the door does not fit in the casing?
Answer:
a) Mean = 0.125 inch
Standard deviation = 0.13975 inch
b) Probability that the width of the casing minus the width of the door exceeds 1/4 inch = P(X > 0.25) = 0.18673
c) Probability that the door does not fit in the casing = P(X < 0) = 0.18673
Step-by-step explanation:
Let the distribution of the width of the casing be X₁ (μ₁, σ₁²)
Let the distribution of the width of the door be X₂ (μ₂, σ₂²)
The distribution of the difference between the width of the casing and the width of the door = X = X₁ - X₂
when two independent normal distributions are combined in any manner, the resulting distribution is also a normal distribution with
Mean = Σλᵢμᵢ
λᵢ = coefficient of each disteibution in the manner that they are combined
μᵢ = Mean of each distribution
Combined variance = σ² = Σλᵢ²σᵢ²
λ₁ = 1, λ₂ = -1
μ₁ = 24 inches
μ₂ = 23 7/8 inches = 23.875 inches
σ₁² = (1/8)² = (1/64) = 0.015625
σ₂ ² = (1/16)² = (1/256) = 0.00390625
Combined mean = μ = 24 - 23.875 = 0.125 inch
Combined variance = σ² = (1² × 0.015625) + [(-1)² × 0.00390625] = 0.01953125
Standard deviation = √(Variance) = √(0.01953125) = 0.1397542486 = 0.13975 inch
b) Probability that the width of the casing minus the width of the door exceeds 1/4 inch = P(X > 0.25)
This is a normal distribution problem
Mean = μ = 0.125 inch
Standard deviation = σ = 0.13975 inch
We first normalize/standardize 0.25 inch
The standardized score of any value is that value minus the mean divided by the standard deviation.
z = (x - μ)/σ = (0.25 - 0.125)/0.13975 = 0.89
P(X > 0.25) = P(z > 0.89)
Checking the tables
P(x > 0.25) = P(z > 0.89) = 1 - P(z ≤ 0.89) = 1 - 0.81327 = 0.18673
c) Probability that the door does not fit in the casing
If X₂ > X₁, X < 0
P(X < 0)
We first normalize/standardize 0 inch
z = (x - μ)/σ = (0 - 0.125)/0.13975 = -0.89
P(X < 0) = P(z < -0.89)
Checking the tables
P(X < 0) = P(z < -0.89) = 0.18673
Hope this Helps!!!
Suppose you pay a dollar to roll two dice. if you roll 5 or a 6 you Get your dollar back +2 more just like it the goal will be to find the amount of money you can expect to win or lose if you play this game 100 times. How many times would you win? how many times would you lose?
Answer:
(a)$67
(b)You are expected to win 56 Times
(c)You are expected to lose 44 Times
Step-by-step explanation:
The sample space for the event of rolling two dice is presented below
[tex](1,1), (2,1), (3,1), (4,1), (5,1), (6,1)\\(1,2), (2,2), (3,2), (4,2), (5,2), (6,2)\\(1,3), (2,3), (3,3), (4,3), (5,3), (6,3)\\(1,4), (2,4), (3,4), (4,4), (5,4), (6,4)\\(1,5), (2,5), (3,5), (4,5), (5,5), (6,5)\\(1,6), (2,6), (3,6), (4,6), (5,6), (6,6)[/tex]
Total number of outcomes =36
The event of rolling a 5 or a 6 are:
[tex](5,1), (6,1)\\ (5,2), (6,2)\\( (5,3), (6,3)\\ (5,4), (6,4)\\(1,5), (2,5), (3,5), (4,5), (5,5), (6,5)\\(1,6), (2,6), (3,6), (4,6), (5,6), (6,6)[/tex]
Number of outcomes =20
Therefore:
P(rolling a 5 or a 6) [tex]=\dfrac{20}{36}[/tex]
The probability distribution of this event is given as follows.
[tex]\left|\begin{array}{c|c|c}$Amount Won(x)&-\$1&\$2\\&\\P(x)&\dfrac{16}{36}&\dfrac{20}{36}\end{array}\right|[/tex]
First, we determine the expected Value of this event.
Expected Value
[tex]=(-\$1\times \frac{16}{36})+ (\$2\times \frac{20}{36})\\=\$0.67[/tex]
Therefore, if the game is played 100 times,
Expected Profit =$0.67 X 100 =$67
If you play the game 100 times, you can expect to win $67.
(b)
Probability of Winning [tex]=\dfrac{20}{36}[/tex]
If the game is played 100 times
Number of times expected to win
[tex]=\dfrac{20}{36} \times 100\\=56$ times[/tex]
Therefore, number of times expected to loose
= 100-56
=44 times
I NEED HELP PLEASE, THANKS! :)
A rock is tossed from a height of 2 meters at an initial velocity of 30 m/s at an angle of 20° with the ground. Write parametric equations to represent the path of the rock. (Show work)
Answer:
x = 28.01t,
y = 10.26t - 4.9t^2 + 2
Step-by-step explanation:
If we are given that an object is thrown with an initial velocity of say, v1 m / s at a height of h meters, at an angle of theta ( θ ), these parametric equations would be in the following format -
x = ( 30 cos 20° )( time ),
y = - 4.9t^2 + ( 30 cos 20° )( time ) + 2
To determine " ( 30 cos 20° )( time ) " you would do the following calculations -
( x = 30 * 0.93... = ( About ) 28.01t
This represents our horizontal distance, respectively the vertical distance should be the following -
y = 30 * 0.34 - 4.9t^2,
( y = ( About ) 10.26t - 4.9t^2 + 2
In other words, our solution should be,
x = 28.01t,
y = 10.26t - 4.9t^2 + 2
These are are parametric equations
The following data represent the miles per gallon for a particular make and model car for six randomly selected vehicles. Compute the mean, median, and mode miles per gallon 24.2. 22.2. 37.8, 22.7. 35 4. 31.61. Compute the mean miles per gallon. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The mean mileage per gallon is _______B. The mean does not exist 2. Compute the median miles per gallon. Select the correct choice below and, if necessary, fill in the answer box to complete your choice A. The median mileage per gallon is __________B. The median does not exist. 3. Compute the mode miles per gallon. Select the correct choice below and, if necessary,fill in the answer box to complete your choice. A. The mode is _________B. The mode does not exist.
Answer:
A. The mean mileage per gallon is _____ 28.99__
A. The median mileage per gallon is _____27.905_____
B. The mode does not exist.
Step-by-step explanation:
Mean= Sum of values/ No of Values
Mean = 24.2 + 22.2+ 37.8+ 22.7 + 35.4 +31.61/ 6
Mean = 173.91/6= 28.985 ≅ 28.99
The median is the middle value of an ordered data which divides the data into two equal halves. For an even data the median is the average of n/2 and n+1/2 value where n is the number of values.
Rearranging the above data
22.2 , 22.7 , 24.2 , 31.61 , 35.4, 37.8
Third and fourth values are =24.2 + 31.61 = 55.81
Average of third and fourth values is = 55.81/2= 27.905
Mode is the values which is occurs repeatedly.
In this data there is no mode.
will give brainliest Evaluate 15/k when k is 3
Answer:
Hey there!
15/k, when k=3
15/3=5
Answer:
5
Step-by-step explanation:
its a simple as 15/3 = 5
have fun
Consider the function represented by 9x + 3y = 12 with x as the independent variable. How can this function be
written using function notation?
Of) = -
O F(x) = - 3x + 4
Of(x) = -x +
O fb) = - 3y+ 4
Answer:
f(x) = -3x + 4
Step-by-step explanation:
Step 1: Move the 9x over
3y = 12 - 9x
Step 2: Divide everything by 3
y = 4 - 3x
Step 3: Rearrange
y = -3x + 4
Step 4: Change y to f(x)
f(x) = -3x + 4
how many solution does this equation have LOOK AT SCREENSHOT ATTACHED
Answer:
One solution
Step-by-step explanation:
99% of the time, linear equations (equations that have the first degree) have only one solution. However, it's always good to check.
6 - 3x = 12 - 6x
6 = 12 - 3x
-3x = -6
x = 2
As you can see, only one solution. Hope this helps!
The problem is: On a Map, 3 inches represents 40 miles, How many inches represents 480 miles?
A cardboard box without a lid is to have a volume of 8,788 cm3. Find the dimensions that minimize the amount of cardboard used.
Answer:
x = y = 26 cm; z = 13 cm
Step-by-step explanation:
We can calculate the dimensions of the square base as
∛(2·8788) = 26 cm
the height of the box will be half of 26/2 which is 13 cm.
x = y = 26 cm; z = 13 cm
then the minimum area for the given volume can be calculated using what we call Lagrange multipliers, this makes it easier
area = xy +2(xz +yz)
But we were given the volume as 8788
Now we will make the partial derivatives of L to be in respect to the cordinates x, y, z, as well as λ to be equal to zero, then
L = xy +2(xz +yz) +λ(xyz -8788)
For x: we have
y+2z +λyz=0
For y we have
y: x +2z +λxz=0
For z we have 2x+2y +λxy=0............eqn(*)
For we have xyz -8788=0
If we simplify the partial derivative equation of y and x above then we have
λ = (y +2z)/(yz).
= 1/z +2/y............eqn(1)
λ = (x +2z)/(xz)
= 1/z +2/x.............eqn(2)
Set eqn(1 and 2) to equate we have
1/z +2/y = 1/z +2/x
x = y
From eqn(*) we can get z
λ = (2x +2y)/(xy) = 2/y +2/x
If we simplify we have
1/z +2y = 2/x +2/y
Then z = x/2
26/2 =13
Therefore,
x = y = 2z = ∛(2·8788)
X= 26
y = 26 cm
z = 13 cm
Which of the following statements about feasible solutions to a linear programming problem is true?A. Min 4x + 3y + (2/3)z
B. Max 5x2 + 6y2
C. Max 5xy
D. Min (x1+x2)/3
Answer:
The answer is "Option A"
Step-by-step explanation:
The valid linear programming language equation can be defined as follows:
Equation:
[tex]\Rightarrow \ Min\ 4x + 3y + (\frac{2}{3})z[/tex]
The description of a linear equation can be defined as follows:
It is an algebraic expression whereby each term contains a single exponent, and a single direction consists in the linear interpolation of the equation.
Formula:
[tex]\to \boxed{y= mx+c}[/tex]
I the horizontal change between two points on a line.
Answer:
m = rise /run = (y2-y1)/(x2-x1)
Step-by-step explanation:
In math, slope is the ratio of the vertical and horizontal changes between two points on a surface or a line. The vertical change between two points is called the rise, and the horizontal change is called the run. The slope equals the rise divided by the run.
Answer: Run is the horizontal change between two points on a line.
Step-by-step explanation:
Determine the logarithmic regression of the data below using either a calculator or spreadsheet program. Then, estimate the x−value when the y−value is 5.2. Round your answer to one decimal place. (4.7,10.7),(7.8,20.6),(10.5,30.2),(15.6,41),(20.8,56.1),(22,65.1). Please help right away! Thank you so much!
Answer:
y ≈ 33.7·ln(x) -45.94.6Step-by-step explanation:
A graphing calculator can perform logarithmic regression, as can a spreadsheet. The least-squares best fit log curve is about ...
y ≈ 33.7·ln(x) -45.9
The value of x estimated to make y = 5.2 is about 4.6.
Joe hypothesizes that the students of an elite school will score higher than the general population. He records a sample mean equal to 568 and states the hypothesis as μ = 568 vs μ > 568. What type of test should Joe do?
Answer:
The test to be used is the right tailed test.
Step-by-step explanation:
The type of test joe should do would be a right tailed test. This is because;
A right tailed test which we sometimes call an upper test is where the hypothesis statement contains the greater than (>) symbol. This means that, the inequality points to the right. For example, we want to compare the the life of batteries before and after a manufacturing change.
If we want to know if the battery life of maybe 90 hours would be greater than the original, then our hypothesis statements might be:
Null hypothesis: (H0 = 90).
Alternative hypothesis: (H1) > 90.
In the null hypothesis, there are no changes, but in the alternative hypothesis, the battery life in hours has increased.
So, the most important factor here is that the alternative hypothesis (H1) is what determines if we have a right tailed test, not the null hypothesis.
Thus, the test to be used is the right tailed test.
Answer:
right tailed test.
Step-by-step explanation:
The average life a manufacturer's blender is 5 years, with a standard deviation of 1 year. Assuming that the lives of these blenders follow approximately a normal distribution, find the probability that the mean life a random sample of 9 such blenders falls between 4.5 and 5.1 years.
Answer:
55.11% probability that the mean life a random sample of 9 such blenders falls between 4.5 and 5.1 years.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes 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.
In this question:
[tex]\mu = 5, \sigma = 1, n = 9, s = \frac{1}{\sqrt{9}} = 0.3333[/tex]
Find the probability that the mean life a random sample of 9 such blenders falls between 4.5 and 5.1 years.
This is the pvalue of Z when X = 5.1 subtracted by the pvalue of Z when X = 4.5. So
X = 5.1
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{5.1 - 5}{0.3333}[/tex]
[tex]Z = 0.3[/tex]
[tex]Z = 0.3[/tex] has a pvalue of 0.6179
X = 4.5
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{4.5 - 5}{0.3333}[/tex]
[tex]Z = -1.5[/tex]
[tex]Z = -1.5[/tex] has a pvalue of 0.0668
0.6179 - 0.0668 = 0.5511
55.11% probability that the mean life a random sample of 9 such blenders falls between 4.5 and 5.1 years.
Find the length and width of a rectangle that has the given perimeter and a maximum area. Perimeter: 116 meters
Answer:
Length = 29 m
Width = 29 m
Step-by-step explanation:
Let x and y be the length and width of the rectangle, respectively.
The area and perimeter are given by:
[tex]A=xy\\p=116=2x+2y\\y=58-x[/tex]
Rewriting the area as a function of x:
[tex]A(x) = x(58-x)\\A(x) = 58x-x^2[/tex]
The value of x for which the derivate of the area function is zero, is the length that maximizes the area:
[tex]A(x) = 58x-x^2\\\frac{dA}{dx}=0=58-2x\\ x=29\ m[/tex]
The value of y is:
[tex]y = 58-29\\y=29\ m[/tex]
Length = 29 m
Width = 29 m
HELP ASAP WILL MARK BRAINIEST IF YOU ARE RIGHT !Which of the following represents a function?
Answer:
Option C.
Step-by-step explanation:
This is a function because all of the numbers have a partner, and none of them have more than one.
Example of Not a Function
Function Not a Function
-4 to 5 -4 to 5 <
9 to 7 -4 to 3 <
13 to 3 13 to 3 ^
-7 to 5 9 to 7 ^
-7 to 5 ^
Not a Function because of this
The chi-square value for a one-tailed (lower tail) test when the level of significance is .1 and the sample size is 15 is a. 23.685. b. 6.571. c. 7.790. d. 21.064.
Answer:
The degrees of freedom are given by:
[tex] df =n-1= 15-1=14[/tex]
And if we look in the chi square distribution with 14 degrees of freedom and if we find a quantile who accumulates 0.1 of the area in the left we got:
[tex] \chi^2 = 7.790[/tex]
And then the best answer would be:
c. 7.790
Step-by-step explanation:
For this case we know that we are using a one tailed (lower tail) critical value using a significance level of [tex]\alpha=0.1[/tex] and for this case we know that the ample size is n=15. The degrees of freedom are given by:
[tex] df =n-1= 15-1=14[/tex]
And if we look in the chi square distribution with 14 degrees of freedom and if we find a quantile who accumulates 0.1 of the area in the left we got:
[tex] \chi^2 = 7.790[/tex]
And then the best answer would be:
c. 7.790
In a survey, 205 people indicated they prefer cats, 160 indicated they prefer dots, and 40 indicated they don’t enjoy either pet. Find the probability that if a person is chosen at random, they prefer cats
Answer: probability = 0.506
Step-by-step explanation:
The data we have is:
Total people: 205 + 160 + 40 = 405
prefer cats: 205
prefer dogs: 160
neither: 40
The probability that a person chosen at random prefers cats is equal to the number of people that prefer cats divided the total number of people:
p = 205/405 = 0.506
in percent form, this is 50.6%
If -5(x+8) =-25, then x=-3
Answer:
Correct!
Step-by-step explanation:
-5(x+8)=-25
x+8=5
x=-3
Answer:
here, -5(x+8)=-25
or, -5x +(-40)= -25
or, -5x=-25+40
or, x= 15/-5
therefore the value of x is -3....ans..
hope u understood..
i am stuck on this please help!
Answer:
[tex]20 {x}^{3} - 36 {x}^{2} + 7x + 3[/tex]Solution,
[tex](5x + 1)(2x - 1)(2x - 3)[/tex]
[tex] = 5x(2x - 1) + 1(2x - 1) \times (2x - 3) \\ = (10 {x}^{2} - 5x + 2x - 1)(2x - 3) \\ = (10 {x}^{2} - 3x - 1)(2 x - 3) \\ = 10 {x}^{2} (2x - 3) - 3x(2 x - 3) - 1(2x - 3) \\ = 20 {x}^{3} - 30 {x}^{2} - 6 {x }^{2} + 9x - 2x + 3 \\ = 20 {x}^{3} - 36 {x}^{2} + 7x + 3[/tex]
Hope this helps..
Good luck on your assignment...
The graphs below are the same shape what is the equation of the blue graph
Answer:
B. g(x) = (x-2)^2 +1
Step-by-step explanation:
When you see this type of equation your get the variables H and K in a quadratic equation. In this case the (x-2)^2 +1 is your H. The (x-2)^2 +1 is your K.
For the H you always do the opposite so in this case instead of going to the left 2 times you go to the right 2 times (affects your x)
For the K you go up or down which in this case you go up one (affects your y)
And that's how you got your (2,1) as the center of the parabola
-Hope this helps :)
[!] Urgent [!] Find the domain of the graphed function.
7. The mean age at first marriage for respondents in a survey is 23.33,
with a standard deviation of 6.13. For an age at first marriage of 33.44,
the proportion of area beyond the Z score associated with this age is
.05. What is the percentile rank for this score?
Answer:
[tex] \mu = 23.33, \sigma =6.13[/tex]
And for this case we are analyzing the value os 33.44 and we can use the z score formula given by:
[tex] z=\frac{X -\mu}{\sigma}[/tex]
And replacing we got:
[tex] z=\frac{33.44 -23.33}{6.13}= 1.649[/tex]
We know that the proportion of area beyond the Z score associated with this age is .05 so then the percentile would be: 95
Step-by-step explanation:
For this case we have the following parameters:
[tex] \mu = 23.33, \sigma =6.13[/tex]
And for this case we are analyzing the value os 33.44 and we can use the z score formula given by:
[tex] z=\frac{X -\mu}{\sigma}[/tex]
And replacing we got:
[tex] z=\frac{33.44 -23.33}{6.13}= 1.649[/tex]
We know that the proportion of area beyond the Z score associated with this age is .05 so then the percentile would be: 95
I need help pls pls pls pls
Answer:
D. 4
Step-by-step explanation:
If he leaves the science assignments for the next day, he will spend zero hours on science assignments. This means that y is equal to 0. Plug this into the given equation and solve for x.
2x + y = 8
2x + 0 = 8
2x = 8
x = 4
Gerald can complete 4 math assignments.
The number of people arriving for treatment at an emergency room can be modeled by a Poisson process with a rate parameter of six per hour.
(a) What is the probability that exactly three arrivals occur during a particular hour? (Round your answer to three decimal places.)
(b) What Is the probability that at least three people arrive during a particular hour? (Round your answer to three decimal places.)
(c) How many people do you expect to arrive during a 15-min period?
Answer:
a) P(x=3)=0.089
b) P(x≥3)=0.938
c) 1.5 arrivals
Step-by-step explanation:
Let t be the time (in hours), then random variable X is the number of people arriving for treatment at an emergency room.
The variable X is modeled by a Poisson process with a rate parameter of λ=6.
The probability of exactly k arrivals in a particular hour can be written as:
[tex]P(x=k)=\lambda^{k} \cdot e^{-\lambda}/k!\\\\P(x=k)=6^k\cdot e^{-6}/k![/tex]
a) The probability that exactly 3 arrivals occur during a particular hour is:
[tex]P(x=3)=6^{3} \cdot e^{-6}/3!=216*0.0025/6=0.089\\\\[/tex]
b) The probability that at least 3 people arrive during a particular hour is:
[tex]P(x\geq3)=1-[P(x=0)+P(x=1)+P(x=2)]\\\\\\P(0)=6^{0} \cdot e^{-6}/0!=1*0.0025/1=0.002\\\\P(1)=6^{1} \cdot e^{-6}/1!=6*0.0025/1=0.015\\\\P(2)=6^{2} \cdot e^{-6}/2!=36*0.0025/2=0.045\\\\\\P(x\geq3)=1-[0.002+0.015+0.045]=1-0.062=0.938[/tex]
c) In this case, t=0.25, so we recalculate the parameter as:
[tex]\lambda =r\cdot t=6\;h^{-1}\cdot 0.25 h=1.5[/tex]
The expected value for a Poisson distribution is equal to its parameter λ, so in this case we expect 1.5 arrivals in a period of 15 minutes.
[tex]E(x)=\lambda=1.5[/tex]
11/n = 8/5 solve for n
Answer:
n = 55/8
Step-by-step explanation:
You can solve it by cross multiplying. Where you multiply the denominator of the fraction on the left side with the numerator on the right side, and vice versa.
11/n = 8/5
n x 8 = 11 x 5
8n = 55
n = 55/8
(or 6.875)
Answer:
[tex]\boxed{\pink{n = 7 \frac{3}{8} }}[/tex]
Step-by-step explanation:
[tex] \frac{11}{n} = \frac{8}{5} \\ [/tex]
Use cross multiplication
[tex]11 \times 5 = 8 \times n \\ 55 = 8n \\ \frac{55}{8} = \frac{8n}{8} \\ n = 7 \frac{3}{8} [/tex]
Kylie and miranda began arguing about who did better on their tests, but they couln't decide who did better given that they took different tests, kylie took a test in Art History and earned a 77.3, and Tan took a test in English and earned a 62.9. Use the fact that all the students' test grades in the Art History class had a mean of 73 and a standard deviation of 10.7, and all the students' test grades in English had a mean of 66.8 and a standard deviation of 10.8 to answer the following questions.
a) Calculate the Z-score for Isaac's test grade.
b) Calculate the 2-score for lan's test grade.
c) Which person did relatively better?
A. Kylie
B. miranda
C. They did equally well.
Answer:
a) 77.3-73/10.7= 0.40187
b) 62.9-66.8/10.8= -0.36111
c) Kylie did relatively better
Step-by-step explanation:
Five thousand tickets are sold at $1 each for a charity raffle. Tickets are to be drawn at random and monetary prizes awarded as follows: 1 prize of $800, 3 prizes of $200, 5 prizes of $50, and 20 prizes of $5. What is the expected value of this raffle if you buy 1 ticket?
Answer:
The expected value of this raffle if you buy 1 ticket is $0.41.
Step-by-step explanation:
The expected value of the raffle if we buy one ticket is the sum of the prizes multiplied by each of its probabilities.
This can be written as:
[tex]E(X)=\sum p_iX_i[/tex]
For example, the first prize is $800 and we have only 1 prize, that divided by the number of tickets gives us a probability of 1/5000.
If we do this with all the prizes, we can calculate the expected value of a ticket.
[tex]E(X)=\sum p_iX_i\\\\\\E(X)=\dfrac{1\cdot800+3\cdot200+5\cdot50+20\cdot20}{5000}\\\\\\E(X)=\dfrac{800+600+250+400}{5000}=\dfrac{2050}{5000}=0.41[/tex]
Conde Nast Traveler publishes a Gold List of the top hotels all over the world. The Broadmoor Hotel in Colorado Springs contains 700 rooms and is on the 2004 Gold List (Conde Nast Traveler, January 2004). Suppose Broadmoor's marketing group forecasts a demand of 670 rooms for the coming weekend. Assume that demand for the upcoming weekend is normally distributed with a standard deviation of 30.
a.What is the probability all the hotel's rooms will be rented (to 4 decimals)?
b. What is the probability 50 or more rooms will not be rented (to 4 decimals)?
Answer:
(a) The probability that all the hotel's rooms will be rented is 0.1587.
(b) The probability that 50 or more rooms will not be rented is 0.2514.
Step-by-step explanation:
We are given that the Broadmoor Hotel in Colorado Springs contains 700 rooms and is on the 2004 Gold List.
Suppose Broadmoor's marketing group forecasts a mean demand of 670 rooms for the coming weekend. Assume that demand for the upcoming weekend is normally distributed with a standard deviation of 30.
Let X = demand for rooms in the hotel
So, X ~ Normal([tex]\mu=670,\sigma^{2} =30^{2}[/tex])
The z-score probability distribution for the normal distribution is given by;
Z = [tex]\frac{X-\mu}{\sigma}[/tex] ~ N(0,1)
where, [tex]\mu[/tex] = mean demand for the rooms = 670
[tex]\sigma[/tex] = standard deviation = 30
(a) The probability that all the hotel's rooms will be rented means that the demand is at least 700 = P(X [tex]\geq[/tex] 700)
P(X [tex]\geq[/tex] 700) = P( [tex]\frac{X-\mu}{\sigma}[/tex] [tex]\geq[/tex] [tex]\frac{700-670}{30}[/tex] ) = P(Z [tex]\geq[/tex] 1) = 1 - P(Z < 1)
= 1 - 0.8413 = 0.1587
The above probability is calculated by looking at the value of x = 1 in the z table which has an area of 0.8413.
(b) The probability that 50 or more rooms will not be rented is given by = P(X [tex]\leq[/tex] 650)
P(X [tex]\leq[/tex] 650) = P( [tex]\frac{X-\mu}{\sigma}[/tex] [tex]\leq[/tex] [tex]\frac{650-670}{30}[/tex] ) = P(Z [tex]\leq[/tex] -0.67) = 1 - P(Z < 0.67)
= 1 - 0.7486 = 0.2514
The above probability is calculated by looking at the value of x = 0.67 in the z table which has an area of 0.7486.
Mia, Maya, and Maria are sisters. Mia's age is twice Maya's age and Maria is seven years younger than Mia. If Maria is 3 years old, how old are Mia and Maya?
Answer:
Mia:10 Maya:5 Maria:3
Step-by-step explanation:
3+7= 10= Mia's age
10÷2=5= Maya's age
Answer:
Mia - 10
Maya - 5
Maria - 3