The given scenario involves analyzing the busyness of a supermarket using probability concepts and distributions. In this case, a Poisson Process is used to model the arrival rate of customers. We will address various aspects of this scenario, including the value of λ, the type of random variable, and probability calculations.
a. In a Poisson Process, λ represents the average rate of events occurring per unit of time. In this case, λ = 90 customers per hour. To calculate the value of λ for a 2.25-hour time interval, we multiply the average rate by the length of the interval, resulting in λ = 90 customers/hour * 2.25 hours = 202.5 customers.
b. The random variable X, representing the number of customers entering the supermarket in the next 10 minutes, is a discrete random variable. This is because the number of customers is counted and can only take on whole number values.
c. i. The probability that 100 shoppers enter the supermarket between 10:00 and 11:00 AM can be calculated using the Poisson probability formula. P(X = k) = (e^(-λ) * λ^k) / k!, where k is the number of events and λ is the average rate. In this case, λ = 90 customers per hour, and the time interval is 1 hour. P(X = 100) can be calculated using the formula.
c. ii. The value used for λ is 90, as it represents the average rate of customers entering per hour. This value is derived from the given information.
d. i. The value of the mean, λ, represents the average number of customers entering the supermarket during the time interval of 5:00 to 6:30 PM. To calculate λ, we multiply the average rate of customers per hour (λ = 90) by the length of the time interval (1.5 hours).
d. ii. To calculate the probability of 150 or more customers entering during this time, we can use the Poisson distribution. By summing the probabilities of having 150, 151, 152, and so on customers, we can determine the probability of being understaffed. If the probability is high, the store manager should consider hiring more staff.
e. i. The waiting time between customer arrivals, represented by the random variable X, is a continuous random variable. This is because the waiting time can take on any real number value within a given range.
e. ii. The exponential distribution models the waiting time between customer arrivals in this case. It is often used to describe continuous random variables involving time between events in a Poisson Process.
e. iii. The average waiting time between customer arrivals can be calculated using the mean of the exponential distribution. The mean waiting time (μ) is equal to the reciprocal of λ (the average arrival rate). So, μ = 1/λ.
e. iv. The probability density function (PDF) for the exponential distribution is given by f(t) = λ * e^(-λt), where t is the waiting time between arrivals and λ is the average arrival rate.
f. The cumulative distribution function (CDF) for the exponential distribution can be calculated by integrating the PDF from 0 to the desired value of t. The formula for the CDF is F(t) = 1 - e^(-λt).
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A supermarket's busyness tends to vary with the approach of a big holiday. The weekend prior to a big holiday, customers entering a small local supermarket follow a Poisson Process with an average rate of 90 per hour.
a. What is the value of 2 in this case? How would the value of a change if you were interested in calculating a probability over a 2.25-hour time interval?
b. Let's say you were interested in the probability of more than 10 customers entering the supermarket in the next 10 minutes. What type (discrete continuous) of random variable would X be and why?
c. i. What is the probability that 100 shoppers enter the supermarket between 10:00 & 11:00 AM?
ii. What value did you use for 1 and why?
d. There tends to be a huge rush between the hours of 5:00 & 6:30 PM when most of the public gets off work. The store manager feels he'll be understaffed if 150 or more enter the supermarket during this time.
i. What is the value of the mean, 1 ?
ii. What is the probability he will be understaffed? Should he consider hiring more staff? Explain. The store manager is interested in studying the waiting time between his customer's arrival.
e. i. What type of random variable discrete/continuous) is X?
ii. What probability distribution models X?
iii. What is the average waiting time between customer's arrival?
iv. Write a formula for the PDF of this distribution that includes the value of its parameter.
f. Calculate the F(T), the cumulative distribution function for the PDF you gave in part e.
A boy who is on the second floor of their house watches his dog lying on the ground. The angle between his eye level and his line of sight is 32º. a. Which angle is identified in the problem, angle of elevation or depression? b. If the boy is 3 meters above the ground, approximately how far is the dog from the house? c. If the dog is 7 meters from the house, how high is the boy above the ground?
As per the given details, the dog is approximately 0.6249 * 3 = 1.8747 meters from the house.
The angle recognized in the problem is the angle of depression. The angle of depression is the attitude between the horizontal line and the line of sight from an observer looking downward.
To calculate approximately how a ways the canine is from the residence, we are able to use trigonometry.
Since the angle of despair is given as 32º and the boy is 3 meters above the floor, we will use the tangent characteristic to find the space.
tan(32º) = (dog's distance / boy's height)
tan(32º) = d / 3
3 * tan(32º) = d
The dog is approximately 0.6249 * 3 = 1.8747 meters from the house.
To calculate how high the boy is above the floor, we are able to again use trigonometry. Since the canine is 7 meters from the residence and the attitude of melancholy is given as 32º, we are able to use the tangent characteristic to discover the peak of the boy.
tan(32º) = (boy's height / dog's distance)
tan(32º) = h / 7
7 * tan(32º) = h
Therefore, the boy is approximately 0.6249 * 7 = 4.3743 meters above the ground.
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If there are 520 grams of radioactive material with a half life of 12 hours how much of the radioactive material will be left after 72 hours? Is the radioactive decay modeled by a linear function or an exponential function
Answer:
16.25 grams are left
exponential
Step-by-step explanation:
Half the material will decay every 12-hour period (the other half will remain).
Initial amount (at time t = 0): 520 grams
Time t = 12: 260 grams are left
Time t = 24: 130 grams are left
Time t = 36: 65 grams are left
Time t = 48: 32.5 grams are left
Time t = 72: 16.25 grams are left
Radioactive decay is modeled by an exponential function. The function can't be linear because for them, equal time steps would produce equal reductions in the amount of material.
find an example of a commutative ring R with 1 in R, and a prime ideal P (of R) with no zero divisors but R is not an integral domain.
An example of a commutative ring R with 1, a prime ideal P, and no zero divisors but R is not an integral domain is the ring R = Z/6Z, where Z is the set of integers and 6Z is the ideal generated by 6.
The ring R = Z/6Z consists of the residue classes of integers modulo 6. The elements of R are [0], [1], [2], [3], [4], and [5], where [a] denotes the residue class of a modulo 6.
In this ring, addition and multiplication are performed modulo 6. For example, [2] + [3] = [5] and [2] * [3] = [0].
R has a multiplicative identity, which is the residue class [1]. It is commutative since addition and multiplication are performed modulo 6.
The ideal P = 2R consists of the elements [0] and [2]. P is a prime ideal since R/P is an integral domain, which means there are no zero divisors in R/P. However, R itself is not an integral domain because [2] * [3] = [0] in R, showing that zero divisors exist in R.
Therefore, the ring R = Z/6Z, with the prime ideal P = 2R, satisfies the given conditions.
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evan has 4 chocolate bars with a total of 48 pices are in each bar
Answer:
what is your question? it seems the answer would be 12 just by looking at this, but still what is the question exactly?
Step-by-step explanation:
Answer: if you are dividing the answer will be 12
(i wrote two since it dosent say what we need to do
if you are multiplying you answer will be 192
hope it helped!
Step-by-step explanation:
a railroad crew can replace 450 meters of rails in 3 days
how many kilometers of rail can they repair in 24 days?
Charles and Lisa were having a apple eating contest. They ate eighteen apples between the two of them. Lisa ate two more apples than Charles. How many apples did Lisa eat?
Answer: She ate 12 apples
Step-by-step explanation: 18 divided by 2 is 9 add 2 of 9 to the other 9 and you get 12 hope I helped
Answer:
she ate 10 apples
Step-by-step explanation:
I thought of it because there is only 18 apples all together
1. John is currently watching 9 different television shows.
a) If John watches one episode of each of these shows, how many orders of shows can he watch?
b) If John wants to download 5 random episodes of these 9 shows, how many combinations exist? (He only downloads 1 episode from any given show.)
c) Out of a group of 12 students competing on the Gymnastics team, how many different ways can a captain, equipment manager, and sound manager be selected at random if no person can hold two positions
a) There are 9! (9 factorial) orders of shows John can watch if he watches one episode of each of the 9 different television shows.
b) There are 126 combinations for John to download 5 random episodes from the 9 shows.
c) There are 1,320 different ways to select a captain, equipment manager, and sound manager from a group of 12 students without any person holding two positions.
a) If John watches one episode of each of the 9 different television shows, the number of orders of shows he can watch is 9!.
b) If John wants to download 5 random episodes of these 9 shows, the number of combinations is given by the binomial coefficient:
C(9, 5) = 9! / (5!(9-5)!) = 126
c) To select a captain, equipment manager, and sound manager from a group of 12 students without any person holding two positions, the number of different ways is given by the product of the choices for each position:
12 * 11 * 10 = 1,320
Therefore, there are 1,320 different ways to select a captain, equipment manager, and sound manager in this scenario.
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Question in pic plz help! ~
Im gonna label the long side of a rectangle a and the smaller side b.
For the perimeter, 2a + 2b = 34
For the area, a x b = 66
if a is 11 and b is 6, the equation for perimeter would be 22 + 12 = 34.
So a = 11 and b = 6
Answer:
Longer side = 11
Shorter side = 6
Step-by-step explanation:
L x W = 66, then W = 66/L
2L + 2W = 34
substitute for W:
2L + 2(66/L) = 34
2L + 132/L = 34
multiply both sides of the equation by L:
2L² + 132 = 34L
divide both sides by 2:
L² + 66 = 17L
L² - 17L + 66 = 0
factor:
(L - 11)(L - 6) = 0
L = 11 or L = 6
if L = 11, then W = 6
if L = 6 then W = 11
4.) Select ALL equivalent expressions to 5x – 5.5. a) 5x -55 c) 5(x - 1.1) b) 2x - 3 + 3x - 2.5 ) 5.5(x - 1)
Answer:
1. (-125 a - 5.75) x + b c (605 x - 550 x^2) + 10.75
2. -125 a x + x (-550 b c x + 605 b c - 5.75) + 10.75
3. 0.25 (-500 a x - 220 b c (10 x - 11) x - 23 x + 43)
Step-by-step explanation:
The value of the Australian dolar (A$) today is $0.73. Yesterday, the value of the Australia dollar was $0.69.
The Australian dollar _______ by ______ %.
a.
appreciated; 5.80
b.
appreciated; 5.48
c.
depreciated; 5.80
d.
depreciated; 4.00
This indicates that the Australian dollar appreciated by 5.80%. the correct answer is (a) appreciated; 5.80.
To determine whether the Australian dollar appreciated or depreciated and by what percentage, we can calculate the percentage change in value between today and yesterday.
The formula for calculating the percentage change is:
Percentage Change = (New Value - Old Value) / Old Value * 100
Using this formula, we can calculate the percentage change:
Percentage Change = (0.73 - 0.69) / 0.69 * 100
Percentage Change = 0.04 / 0.69 * 100
Percentage Change ≈ 5.80
The percentage change is approximately 5.80%. This indicates that the Australian dollar appreciated by 5.80%.
Therefore, the correct answer is (a) appreciated; 5.80.
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a cone has a height of 7ft and a radius 4ft. Which equation can find the volume of the cone?
PLEASE I ACTUALLY NEED HELP
Answer:
B
Step-by-step explanation:
equation for volume of a cone = [tex]V=\frac{1}{3}\pi r^2h[/tex]
plug in - [tex]V=\frac{1}{3} \pi (4)^2(7)[/tex]
Answer:
we have
volume of cone =1/3 πr²h=1/3×π×4²×7ft³
so
v=1/3 π(4²)(7)ft³
Jamal has a new business as a financial consultant. He uses the formula y = 1,500x + 500 as a starting point for new customers. Y is the total amount of money and x is the number of years of investments. What is the total amount of money a dient would have after 7 years?
Answer:
11,000
Step-by-step explanation:
You would multiply 1,500 by 7 and then add 500.
2. You were 22 inches tall at birth, and 48 inches tall on your 8th birthday.
2a) On average, how many inches did you grow per year? (Hint: in 8 years 2 points
you grow a total of 26 inches) include units!!
Answer:
3.25
Step-by-step explanation:because you have to divide the years with the inches so in each year i would grow about 3.25 inches
which tool is not needed to construct a perpendiculer bisecter
Answer:
a protractor is not needed to constant a perpendicular bisecter
Step-by-step explanation:
please mark brainliest
Is 41.77 a integer?
Answer:
nope, an integer must be a whole number, no fractions / decimals
Step-by-step explanation:
Answer:
No
Step-by-step explanation:
An integer is a whole number or a number that is not a fraction or decimal. So, since 41.77 is a decimal it cannot be an integer. Examples of integers are 41 or -2.
explain how to graph the circle by hand on the coordinate plane (3 points)
First find the center, then graph all the points that are at a distance of R units from that center.
How to graph a circle by hand?A circle of radius R is the set of all points that are at a distance R from a given point (the center of the circle).
So to graph it, we need to know these two things, radius and center.
Once we do, first we graph the center on the coordinate plane.
Once we find the center, we can find all the poiints that are at a distance of R units from our center, so we need to graph these. Once we do, we will have the graph of our circle on the coordinate plane.
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ILL MARK BRAINLIESTTTTT
Answer:
0.075 inches per year
Step-by-step explanation:
The average rate of change is measured as
( difference in diameter ) ÷ ( difference in years )
= ( 251 - 248 ) ÷ ( 2005 - 1965 )
= 3 inches ÷ 40 years
= 0.075 inches per year
Consider the following algorithm that takes inputs a parameter 0
function integer X(p,n)The algorithm described simulates a random variable with a binomial distribution of parameters p and n.
The given algorithm involves generating random numbers and incrementing a variable X based on certain conditions. The variable X represents the number of successes or "1" outcomes in a sequence of n independent Bernoulli trials, where each trial has a probability of success equal to p.
In each iteration of the loop, the algorithm generates a random number between 0 and 1 (denoted as RND) and compares it to the probability parameter p. If the generated random number is less than or equal to p, the variable X is incremented by 1.
This process is repeated for a total of n trials, resulting in the count of successes, which follows a binomial distribution. The binomial distribution represents the number of successes in a fixed number of independent Bernoulli trials, where each trial has the same probability of success, given by parameter p. Therefore, the algorithm simulates a random variable with a binomial distribution of parameters p and n.
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Sketch two periods of the graph of the function h(x)=4sec(π4(x+3)). Identify the stretching factor, period, and asymptotes.
Enter the exact answers.
Stretching factor = ____________
Period: P=
__________
Enter the asymptotes of the function on the domain [−P,P].
To enter π, type Pi.
The field below accepts a list of numbers or formulas separated by semicolons (e.g. 2;4;6 or x+1;x−1). The order of the list does not matter.
Asymptotes: x=
__________
Select the correct graph of h(x)=4sec(π4(x+3)).
(a) (b) (c) (d)
The function h(x) = 4sec(π/4(x+3)) represents a graph with a stretching factor of 4 and a period of 8π/4 = 2π. The correct graph representation of h(x) = 4sec(π/4(x+3)) needs to show these characteristics. The correct answer would be (b).
The function h(x) = 4sec(π/4(x+3)) has a stretching factor of 4, which means that the amplitude of the function is multiplied by 4, causing the graph to be vertically stretched.
The period of the function is given by P = 2π/π/4 = 8π/4 = 2π. This means that the graph will complete two periods within the interval [-P, P], which in this case is [-2π, 2π].
The asymptotes of the function occur at x = -P/2 and x = P/2. Substituting the value of P = 2π, the asymptotes are x = -π and x = π. These vertical asymptotes indicate where the graph approaches infinity or negative infinity as x approaches these values.
To determine the correct graph representation of h(x) = 4sec(π/4(x+3)), you would need to choose the graph option that shows the stretching factor of 4, a period of 2π, and vertical asymptotes at x = -π and x = π.
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What is the answer with explanation?
The value of arc ABD is determined as 236⁰.
Option C.
What is the measure of arc ABD?The value of arc ABD is calculated by applying intersecting chord theorem, which states that the angle at tangent is half of the arc angle of the two intersecting chords.
Also this theory states that arc angles of intersecting secants at the center of the circle is equal to the angle formed at the center of the circle by the two intersecting chords.
arc BA = 2 x 48⁰ (interior angles of intersecting secants)
arc BA = 96⁰
arc BD = 2 x 70⁰ (interior angles of intersecting secants)
arc BD = 140⁰
arc ABD = arc BA + arc BD
arc ABD = 96⁰ + 140⁰
arc ABD = 236⁰
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1. Write an equation for the circle whose graph is shown.
y
5
3
2
-5 -4 -3 -2 -1
1 2 3 4 5 x
2
3
-4
-5
O (3-1)2 + (y + 2)2 = 2
O (3-1)2 + (x + 2)2 = 4
O (2+1)2 + (y – 2)2 = 4
O (2+1)2 + (y-2)2
Answer:
325
Step-by-step explanation:
got it right on edg
The required equation of the circle that shown in the graph is,
(x + 1)² + (y - 2)² = 4 where (-1 , 2) is the center of the circle and 2 unit is the radius of the circle. Option C is correct.
A graph of the circle is shown, It is to determine the equation of the circle.
The circle is the locus of a point whose distance from a fixed point is constant i.e center (h, k). The equation of the circle is given by
(x - h)² + (y - k)² = r²
where h, k is the coordinate of the circle's center on the coordinate plane and r is the circle's radius.
From the graph, the center is ( -1, 2) and the radius is 2. Now put these values in the standard equation of the circle.
(x - (-1))² + (y - 2)² = 2²
(x +1 )² + (y - 2)² = 4
Thus, the required equation of the circle that shown in the graph is,
(x + 1)² + (y - 2)² = 4 where (-1 , 2) is center of the circle and 2 unit is the radius of the circle. Option C is correct.
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Tucker purchased $4,600 in new equipment for a catering business. He estimates that the value of the equipment is reduced by approximately 40% every two years. Tucker states that the function V(t)=4,600(0.4)2t could be used to represent the value of the equipment, V, in dollars t years after the purchase of the new equipment. Explain whether the function Tucker stated is correct, and, if not, determine the correct function that could be used to find the value of the equipment purchased.
show work
Answer:
The function stated by Tucker is incorrect.
V(t) = 4600(0.8)^t
Step-by-step explanation:
Given the function :
V(t)=4,600(0.4)2t
The initial value of equipment = 4600
Decay rate = 40% of very 2 years
The value of equipment t years after purchase
The exponential decat function goes thus :
V(t) = Initial value * (1 - decay rate)^t
The Decay rate per year = 40% /2 = 20% = 0.2
V(t) = 4600(1 - 0.2)^t
V(t) = 4600(0.8)^t
Find the equation for the following parabola. Focus (3,4) Directrix y 2 A. (x-3)2-2 (y-2.5) B. (x-3)2 = 4(y-3) C. (x-3)2 = (y-4) D. (y-3)2-4 (x-3) Enter
To find the equation of a parabola given its focus and directrix, we use the standard form of the equation of a parabola which is:
[tex]\frac{(y-k)^2}{4a} = x-h[/tex]
Where (h,k) is the vertex of the parabola, and a is the distance between the vertex and the focus (or between the vertex and directrix, they're equal).
Therefore, the answer is option D, (y-3)²-4(x-3).
Using this formula, let's first find the vertex of the parabola. Since the directrix is a horizontal line, the vertex lies halfway between the focus and directrix on the y-axis. Thus, the vertex is at (3,3).
Since the focus is above the vertex, a is positive, and its value is the distance between the vertex and focus:
a = 4 - 3
= 1
Substituting these values into the standard form of the equation of a parabola gives:
[tex]\frac{(y-3)^2}{4(1)} = x - 3$$[/tex]
[tex]\frac{(y-3)^2}{4} = x - 3$$[/tex]
Multiplying both sides by 4 gives:
y - 3 = 2(x - 3)
y = 2x - 3
Therefore, the answer is option D, (y-3)²-4(x-3).
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1. 2
given that c = 2πr an, write an expression
for r.
Answer:
r = c / 2π
Step-by-step explanation:
c = 2πr is the formula for the circumference of a circle of radius r.
We can solve this for r:
r = c / (2pi)
or
r = c / 2π
Evaluate 4 + (m - n)
When m = 7 and n = 5.
Each side of a square is increased 3 inches. When this happens, the area is multiplied by 25. How many inches in the side of the original square?
Answer:
s = 0.75 inches
Step-by-step explanation:
Let s = side length of the original square
s + 3 = side length of the new square
Area of a square = s²
A = s²
A = (s+3)²
A = s² + 6s + 9
Area multiplied by 25 = 25 * s²
So,
s² + 6s + 9 = 25s²
25s² - s² - 6s - 9 = 0
24s² - 6s - 9 = 0
8s² - 2s - 3 = 0
a = 8
b = -2
c = -3
s = -b ± √b² - 4ac / 2a
= -(-2) ± √(-2)² - 4(8)(-3) / 2(8)
= 2 ± √4 - (-96) / 16
= 2 ± √100 / 16
= 2 ± 10/16
s = 2 + 10/16 or 2-10/16
= 12/16 or -8/16
= 0.75 or -0.5
side length can not be negative
Therefore, s = 0.75
A = s²
A = (0.75)²
= 0.5625
A = (s+3)²
= (0.75+3)²
= 3.75²
= 13.95
Use the standard normal distribution or the disebution to constructa confidence interval for the popolnoma Antly you decided why the In a random sample of 45 people, the mean body mass index (BMI) 27 B and the standard devion was 616 Which distribution should be used to contact the condence interval? Choose the correct below O A Use a normal distributor because the sample is rondom the population and on OB. Use anomal distribution because the same is random na 30 known OC Uldistribution because the sales and the population is not an unknown OD Use adidinotion because the sample random and unknown OE. Neither a normal dishon nordisbution can be because the samples and and the now to becoma
A confidence interval for the population mean (BMI) based on a
random
sample of 45 people, a normal distribution should be used because the sample is random and the population is known.
In this scenario, the sample size is sufficiently large (n = 45), and the population standard
deviation
(σ = 6.16) is known. When these conditions are met, the appropriate distribution to construct a confidence interval for the population mean is the normal distribution. The central limit theorem states that when the sample size is large, the distribution of the sample mean approaches a
normal
distribution regardless of the shape of the population distribution.
Using the normal distribution, we can calculate the
standard
error of the mean (SEM) by dividing the population standard deviation by the square root of the sample size: SEM = σ / √n. In this case, the SEM would be 6.16 / √45. The confidence
interval
can then be calculated by multiplying the SEM by the appropriate critical value for the desired level of confidence (e.g., 95%) and adding/subtracting it to/from the sample mean.
Therefore, to construct a confidence interval for the population mean BMI, we would use a normal
distribution
because the sample is random, and the population standard deviation is known.
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I=7 m, w=4 m, h= 3 m
The volume of the room with the given dimensions is 84 cubic meters.
The volume of a room can be calculated by multiplying its length, width, and height. In this case, the given dimensions are:
Length (L) = 7 m
Width (W) = 4 m
Height (H) = 3 m
To find the volume, we can use the formula:
Volume = Length × Width × Height
Substituting the given values:
Volume = 7 m × 4 m × 3 m
Simplifying:
Volume = 84 m³
Therefore, the volume of the room with the given dimensions is 84 cubic meters.
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In Exercises 7-12, complete the square in order to put the equation into standard form. Identify the center and the radius or explain why the equation does not represent a circle.
7. x ^ 2 - 12x + y ^ 2 + 6y = - 9
9. x ^ 2 + y ^ 2 + 14x - 20y - 20 = 0
x ^ 1 - 2x + y ^ 1 + 3/2 * y = - 1
8- 3x ^ 2 - 3y ^ 2 + 27y + 61 = 0
10. x ^ 2 + y ^ 2 - 7x - 3y - 1 = 0
12. 4x ^ 2 - 16x + 4y ^ 2 + 16 = 0
Here are the solutions to each problem, which include the center and radius for each circle:7. Center: (6, -3); Radius: 6.9. Center: (-7, 10); Radius: 13.11. Center: (1, -2); Radius: 1/2.8. Center: (0, 9); Radius: 3/2.10. Center: (7/2, 3/2); Radius: 5/2.12. Center: (2, 0); Radius: 1.
The solution is given as follows;7. x² - 12x + y² + 6y = - 9.
We start by grouping the x and y terms separately, then completing the square by adding half of the coefficient of the respective variable and squaring the result. x² - 12x + y² + 6y = - 9(x² - 12x + __) + (y² + 6y + __) = - 9 + __ + __
Now, we'll fill in the blanks in the parentheses so that the trinomials are perfect squares: (x² - 12x + 36) + (y² + 6y + 9) = - 9 + 36 + 9.
This simplifies to: (x - 6)² + (y + 3)² = 36.
The center of the circle is (6, −3), and its radius is 6.9. x² + y² + 14x - 20y - 20 = 0.
First, we group the x terms and the y terms separately:x² + 14x + y² - 20y = 20.
Now, we'll complete the square in both x and y. x² + 14x + y² - 20y = 20(x² + 14x + __) + (y² - 20y + __) = 20 + __ + __.
We'll fill in the blanks so that the trinomials are perfect squares.
To find the terms to add, we take half of the coefficient of the variable and square it. (x² + 14x + 49) + (y² - 20y + 100) = 20 + 49 + 100
Simplifying, we get (x + 7)² + (y - 10)² = 169.
The center of the circle is (-7, 10), and its radius is 13.x - 2x + y + 3/2y = -1
We first rearrange the terms. x - 2x + y + 3/2y = -1-x - 1/2y = -1
We then complete the square in x and y as follows. x - 2x + y + 3/2y = -1(x - 1) - (1/2)(y + 2) = -1/2(x - 1)² - 1/4(y + 2)² = 1/2
The center of the circle is (1, -2) and its radius is 1/2.8. - 3x² - 3y² + 27y + 61 = 0
We rearrange and group the terms. - 3x² - 3y² + 27y = -61
We then complete the square. - 3x² - 3(y² - 9y + 81/4) + 27(81/4) = -61 - 3(81/4)(x² + (y - 9/2)² = 405/4
The center of the circle is (0, 9) and its radius is 3/2.10. x² + y² - 7x - 3y - 1 = 0
We rearrange and group the terms. x² - 7x + y² - 3y = 1
We then complete the square. x² - 7x + 49/4 + y² - 3y + 9/4 = 1 + 49/4 + 9/4(x - 7/2)² + (y - 3/2)² = 25/4
The center of the circle is (7/2, 3/2), and its radius is 5/2.12. 4x² - 16x + 4y² + 16 = 0
We rearrange and group the terms. 4x² - 16x + 4y² = -16
We then complete the square. 4(x² - 4x + 4) + 4y² = 0(x - 2)² + y² = 1
The center of the circle is (2, 0), and its radius is 1.
Completing the square is a method used to turn quadratic expressions in standard form into perfect squares. It’s often used to find the center and radius of circles.
Here are the solutions to each problem, which include the center and radius for each circle:7. Center: (6, -3); Radius: 6.9. Center: (-7, 10); Radius: 13.11. Center: (1, -2); Radius: 1/2.8. Center: (0, 9); Radius: 3/2.10. Center: (7/2, 3/2); Radius: 5/2.12. Center: (2, 0); Radius: 1.
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g a tank contains 90 kg of salt and 1000 l of water. a solution of a concentration 0.045 kg of salt per liter enters a tank at the rate 8 l/min. the solution is mixed and drains from the tank at the same rate what is the concentration of our solution in the tank initially?
The final concentration in the tank is 0.045 kg/L, which is the same as the concentration of the incoming solution.
To solve the problem, we can use the formula:
C1V1 + C2V2 = C3V3
where C1 is the initial concentration, V1 is the initial volume, C2 is the concentration of the incoming solution, V2 is the volume of the incoming solution, C3 is the final concentration, and V3 is the final volume.
We know that the initial volume of the tank is 1000 L and it contains 90 kg of salt. To find the initial concentration, we need to convert the mass of salt to concentration by dividing it by the total volume:
90 kg / 1000 L = 0.09 kg/L
This means that initially, the concentration of salt in the tank is 0.09 kg/L.
Next, we need to calculate how much salt enters and leaves the tank during a given time period. Since the incoming solution has a concentration of 0.045 kg/L and enters at a rate of 8 L/min, it brings in:
0.045 kg/L x 8 L/min = 0.36 kg/min
The outgoing solution has the same concentration as the final concentration in the tank, so we can use this formula to find it:
C1V1 + C2V2 = C3V3
(0.09 kg/L)(1000 L) + (0.045 kg/L)(8 L/min)(t min) = C3(1000 L + 8 L/min)(t min)
Simplifying and solving for C3, we get:
C3 = (0.09 kg/L)(1000 L) + (0.045 kg/L)(8 L/min)(t min) / (1000 L + 8 L/min)(t min)
At steady state, when the amount of salt entering and leaving the tank is equal, we can set the incoming and outgoing terms equal to each other:
0.36 kg/min = C3(8 L/min)
Solving for C3, we get:
C3 = 0.045 kg/L
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