Use spherical coordinates. Evaluate
∭B(x2+y2+z2)2dV∭B(x2+y2+z2)2dV,
where B is the ball with center the origin and radius 1.

(a) The differential Equation that is satisfied by y is dy/dt = k × y × (1 - y)   ,

(b) Solution of the differential equation assuming y(0) = c is y = [tex]\frac{1}{(\frac{1-c}{c})e^{-kt} +1 }[/tex] .

In the question ,

Part (a)

let the fraction of people who heard the rumor is = y

So , the fraction who have not heard the rumor is = 1 - y .

the rate of rumor spread is ⇒ dy/dt = k×y(1 - y)

dy/y(1-y) = k.dt     ...where k is the constant of proportionality .

So , the differential equation is ..

dy/dt = k × y × (1 - y)

Part (b)

So , 1/y(1-y) = 1/y + 1/(1 - y)       ....equation(1)

integrating equation(1) , we get

∫dx/(1 + ax) = ㏑(1 + ax)/a     ,....where a is the constant

㏑y + ㏑(1-y)/(-1) = kt + d     ,.....where d is the constant

By using , ㏑a - ㏑b = ㏑(a/b) and taking exponential . we get ,

y/(1 - y) = c₁[tex]e^{k\times t}[/tex]

for t = 0 and y(0) = c

solving further , we get

c₁ = c/(1 - c)

So , y = (1-y)c₁[tex]e^{k\times t}[/tex]

y(1 + c₁[tex]e^{k\times t}[/tex]) = c₁[tex]e^{k\times t}[/tex]

y = c₁[tex]e^{k\times t}[/tex]/(1 + c₁[tex]e^{k\times t}[/tex])

taking c₁[tex]e^{k\times t}[/tex] common , and substituting the value of c₁ we get ,

the solution as , y = [tex]\frac{1}{(\frac{1-c}{c})e^{-kt} +1 }[/tex]    .

Therefore , (a) the differential equation is dy/dt = k × y × (1 - y)   and

(b) the solution is y = [tex]\frac{1}{(\frac{1-c}{c})e^{-kt} +1 }[/tex]   .

The given question is incomplete , the complete question is

One model for the spread of a rumor is that the rate of spread is proportional to the product of the fraction y of the population who have heard the rumor and the fraction who have not heard the rumor.

(a) Write a differential equation that is satisfied by y. (Use k for the constant of proportionality.)

(b) Solve the differential equation. Assume y(0) = C.

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1) The enrollment in 2016 will be 7500.

2) In 2026 year the enrollment reach 10,000.

Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.

Given that;

The function f(x) represents the number of enrollment.

Defined as;

⇒ F(x) = 250x + 6000

Where x represents year since 2010.

(1) Now for finding the enrollment in 2016;

Put x = 2016 - 2010 = 6 in the function

⇒ F(6) = 250x6 + 6000

          = 7500

Thus, The required number of enrollment = 7500

(2) Now we have to find the year in which enrollment reach 10,000;

i.e f(x) = 10,000

=> 250x + 6000 = 10000

=> 250x = 4000

=> x = 16

Thus, The required year = 2010 + 16

                                     = 2026 answer.

1) The enrollment in 2016 will be 7500.

2) In 2026 year the enrollment reach 10,000.

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The solution to the systems of equations is (4,1). Option C. is the answer

An algebraic equation is when two expressions are set equal to each other, and at least one variable is included

Given the: equations {(y=x²-2x+4), (y=3x):}

y= x²-2x+4 and y = 3x

substitute y = 3x into y= x²-2x+4. That is:

y= x²-2x+4

3x =  x²-2x+4

x²-2x -3x+4 = 0

x²-5x+4 = 0

By factoring:

x²-4x -1x+4 = 0

x(x-4) -1(x-4) = 0

(x-4)(x-1) = 0

x-4 = 0 or x-1 = 0

x= 4 or x = 1

Thus, the solution is (4,1)

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The ratio of rainy days to total days written as a percent will be 75%.

Ratio demonstrates how many times one number can fit into another number. Ratios contrast two numbers by ordinarily dividing them. A/B will be the formula if one is comparing one data point (A) to another data point (B).

Ratio is used to compare two or more numbers. It is also used to indicate how big or small a quantity is when it is compared to another. It should be noted that in a ratio, two quantities are compared using division.

Since in the last 24 days, it rained 18 days.

Number of rainy days = 18.

Number of total days = 24

The ratio of rainy days to total days written as a percent will be:

= Number of rainy days / Total days × 100

= 18/24 × 100

= 3/4 × 100

= 75%

Therefore, the ratio is 3:4 which is 75%.

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The correct answer is A) y = 9000x + 65,000.

The correct answer is A) y = 9000x + 65,000.

The house has increased in value by 54,000 ($119,000 - $65,000) over 6 years (change in x), so the slope must be 9000 (54,000/6).

The equation y = 9000x + 65,000

models the value of the house after x years, where y is the value of the house,

9000x is the slope of the equation,

and 65,000 is the y-intercept.

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The volume of the largest right circular cylinder is [tex]=\frac{4\pi r^3}{3\sqrt{3} }[/tex] cu. unit

Now, According to the question:

The given sphere is of radius R.

Let h be the height and r be the radius of the cylinder inscribed in the sphere.

We know that:

Volume of cylinder

V = [tex]\pi R^2h[/tex]    .....(1)

In right Triangle OBA

[tex]AB^2 + OB^2 = OA^2[/tex]

[tex]R^2 + \frac{h^2}{4} = r^2[/tex]

So, [tex]R^2 = r^2 - \frac{h^2}{4}[/tex]

Putting the value of [tex]R^2[/tex] in equation (1), We get

V = [tex]\pi (r^2 - \frac{h^2}{4} )h[/tex]

V = [tex]\pi (r^2h - \frac{h^3}{4} )[/tex]   ....(2)

dV/dh = [tex]\pi (r^2 - \frac{3h^2}{4} )[/tex] .....(3)

For, Stationary point, dV/dh = 0

[tex]\pi (r^2 - \frac{3h^2}{4} )[/tex] = 0

[tex](r^2 - \frac{3h}{4} )[/tex]   => [tex]h^2 - \frac{4r^2}{3}[/tex] => [tex]h - \frac{2r}{\sqrt{3} }[/tex]

Now, [tex]\frac{d^2V}{dh^2} = \pi (-\frac{6}{4}h )[/tex]

[tex][\frac{d^2V}{dh^2}]_a_t_h_=_\frac{2r}{\sqrt{3} }[/tex]   = x[-3/2 , [tex]2r/\sqrt{3}[/tex]]< 0

Volume is maximum at h = 2r/[tex]\sqrt{3}[/tex]

Maximum volume is :

[tex]= \pi (r^2.\frac{2r}{\sqrt{3} }- \frac{1}{4}.\frac{8r^3}{3\sqrt{3} } )[/tex]

[tex]=\pi (\frac{2r^3}{\sqrt{3} }-\frac{2r^3}{3\sqrt{3} } )[/tex]

[tex]=\pi (\frac{6r^3-2r^3}{3\sqrt{3} } )[/tex]

[tex]=\frac{4\pi r^3}{3\sqrt{3} }[/tex] cu. unit

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Answer:

The answer is :

E - 6c + 4t < 300

Hence, the speed that Rick must be driving on to even with Bobby at the end of the 16th lap should be: Distance = Speed × Time16=1084× Speed Speed=16×8410=134.4 mph.

The time taken by Bobby to complete 10 laps will be:

[tex]$$\begin{aligned}\text { Distance } & =\text { Speed } \times \text { Time } \\10 & =84 \times \text { Time } \\\text { Time } & =\frac{10}{84} \text { hours }\end{aligned}$$[/tex]

Hence, the speed that Rick must be driving on to even with Bobby at the end of the 16 th lap should be:

[tex]$$\begin{aligned}\text { Distance } & =\text { Speed } \times \text { Time } \\16 & =\frac{10}{84} \times \text { Speed } \\\text { Speed } & =\frac{16 \times 84}{10}=134.4 \mathrm{mph} .\end{aligned}$$[/tex]

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The value of 'a' can be 20. The correct option is C, 20.

As per the triangle inequality theorem, the sum of any two sides of the triangle should be greater than the third side.

As per triangle inequality theorem, the sum of the two sides of the triangle should be greater than the third side of the triangle.

As per the triangle inequality theorem, if 'a' is the longest side of the triangle then,

21 + 6 > a

27 > a

If a is not the longest side of the triangle,

21 + a > 6

a > -21 + 6

a > -15

6 + a  > 21

a > 21 - 6

a > 15

Therefore, the value of a should be greater than 15 and less than 27. Since the only option under this condition is 20.

Hence, The correct option is C, 20.

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Answer:

1000

Step-by-step explanation:

If any of the digits 0-9 can be used then there are 10^3 possible codes.

10^3 = 1000

Part 1

[tex]-4.9t^2 +18.24t+0.8=-1.43t+4.26\\\\-4.9t^2 +19.67t-3.46=0\\\\\Delta =(19.67)^2 -4(-4.9)(-3.46)=319.0929 > 0[/tex]

Therefore, the blocker can knock down the punt.

Part 2

Using the quadratic formula,

[tex]t=\frac{-19.67 \pm \sqrt{319.0929}}{2(-4.9)}\\\\t \approx 0.18437, 3.82992[/tex]

Considering the graphs, it is clear to take the smaller solution. Thus, the point of intersection is [tex](0.18437, h(0.18437))=\boxed{(0.18437, 3.99635)}[/tex].

The solution of the equation written as an imaginary number is y =  3i or -3i

An imaginary number is a number of the form ai, where a is a real number and i is the square root of -1. Imaginary numbers are often denoted with the letter "i".

Given: y² + 11 = 2

y² + 11 = 2

y² = 2 - 11

y² = -9

y = ±√-9                      

y = ± 3i

y = 3i or -3i

(Note: √9 = 3 and √-9 = 3i)

Thus, the solution is y =  3i or -3i

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Answer:

x = [tex]\frac{5-3y}{2}[/tex]

Step-by-step explanation:

2x + 3y = 5

isolate variable: 2x = 5-3y

divide by 2: x = [tex]\frac{5-3y}{2}[/tex]

Standard deviation will be √3.3516 .

To calculate the standard deviation for the given data first we have to calculate the total number of students , mid value , fiXi , fiXi².

After that , we have to calculate the Xbar by using

Xbar = ∑fiXi / N

for which we need the value of fi , Xi and N

N = 100

fiXi = 6478

we have calculated the values from the given data ,

Therefore ,

Xbar = 6478 / 100

= 64.78

Var(X) = αx² - ∑fiXi² / N - (Xbar²)

= 419980 / 100 - (64.78)²

= 4199.80 -4196.4484

=3.3516

Thus,

standard deviation ax = √var(X)

= √3.3516

Therefore , the standard deviation will be  √3.3516

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The angles after solving the equations will be equal to 50°, and both angles will be the same as the corresponding angles. Hence, option B is correct.

An angle results from the intersection of two lines at a point. The term "angle" describes the width of the "gap" that exists between these two rays. It's represented by the symbol.

Angles are most frequently measured in degrees and radians, a measurement of roundness or rotation. Angles are a part of everyday existence.

As per the given information in the question,

The equations for the angles are:

7x + 1 = 6x + 8

7x - 6x = 8 - 1

x = 7

So, the angles will be,

7x + 1 = 7(7) + 1 = 50°

6x + 8 = 6(7) + 8 = 50°

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Answer:

70

Step-by-step explanation:

The Null Hypothesis, H0 is "Marble color preference and income class are independent" and the Alternate Hypothesis, H1 is "Marble color preference and income class are dependent".

The null and alternative are always claims about the population. That’s because the goal of hypothesis testing is to make inferences about a population based on a sample. Often, we infer whether there’s an effect in the population by looking at differences between groups or relationships between variables in the sample. It’s critical for your research to write strong hypotheses.

We can use a statistical test to decide whether the evidence favors the null or alternative hypothesis. Each type of statistical test comes with a specific way of phrasing the null and alternative hypotheses. However, the hypotheses can also be phrased in a general way that applies to any test.

We are given that to test the claim that marble color preference and club membership are related.

Thus, the Null Hypothesis, H0 is "Marble color preference and income class are independent" and the Alternate Hypothesis, H1 is "Marble color preference and income class are dependent".

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Using a system of equations, the number of seats in the upper section of the racetrack is 3,600.

A system of equations, also called simultaneous equations, is two or more equations solved concurrently.

We can use any of the following methods to solve simultaneous equations:

In this situation, after forming the equations, we can use substitution and elimination methods to solve them.

Racetrack charge per lower seat = $85

Racetrack charge per upper seat = $60

Racetrack charge per field ticket = $35

Let lower seats = x

Let upper seats = 3x

Let field tickets = y

4x + y = 22,800 ... Equation 1

y = 22,800 - 4x ...Equation 3

85x + 60(3x) + 35y = 948,000

85x + 180x + 35y = 948,000 ... Equation 2

Substitute Equation 3 in Equation 2 to eliminate y:

85x + 180x + 35(22,800 - 4x) = 948,000

85x + 180x + 798,000 - 140x = 948,000

125x = 948,000 - 798,000

125x = 150,000

x = 1,200

Determining the number of seats:

Seats in the Lower section = 1,200

Seats in the Upper section = 3,600 (1,200 x 3)

Field tickets, y = 22,800 - 4x

y = 22,800 - 4(1,200)

= 18,000

Check:

85x + 180x + 35y = 948,000

85(1,200) + 180(1,200) + 35(18,000) = 948,000

102,000 + 216,000 + 630,000 = 948,000

948,000 = 948,000

Thus, based on simultaneous equations, there are 3,600 seats in the upper section of the racetrack.

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Answer:

Yes, there are many people who can help you with a finance question. Some of the people who can help you include: financial advisors, accountants, financial planners, and financial analysts. Additionally, there are many online resources available such as personal finance forums, websites, and blogs.

Step-by-step explanation:

It takes about 120 years for the graph to reach 100 million barrels per day whereas it takes 50 years to go from 100 million to 200 million.

As per the question the left axis indicates the amount of oil in the earth in trillions of barrels.

The right axis indicates the global consumption rate of oil in millions of barrels per day.

To the left of the red vertical line are model results that approximate reality whereas to the right are model-based predictions of the future.

The bottom axis is time in years.

The graph attached at the end of the solution.

Let the number of years of transition from using no oil to consuming 100 million barrels per day be a.

Let the number of years of transition from using 100 million to 200 million barrels per day be b.

From the given graph, we can see that initial consumption rate is low, and it takes 120 years for the graph to reach 100 million barrels.

But it takes 50 years to go from 100 million to 200 million.

This is known as exponential growth.

Therefore, the value of a is 120 and the value of b is 50.

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Answer:

x1,y16 is the rate of change

Step-by-step explanatI subtracted 13-32 which gives me 16, then I added 16 to 32 to be sure and it gave me 48 so the change on the Y axis is going up by 16 and x axis is going up by 1

The Probability of, a ace, jack of clubs, King or queen of diamonds appears in drawing a single card from a well shuffled ordinary deck of 52 cards is 4/13.

As per the given data,

we need to find out the probability of, King, ace, jack of clubs or queen of diamonds appears in drawing a single card from a well shuffled ordinary deck of 52 cards.

We know that,

Probability(Event) =Number of Favorable Outcomes/Total number of

                                Outcomes = x/n.    

Total number of Outcomes is 52 (given)

So,  we will calculate Number of Favorable Outcomes as follows:

The total no. of King in deck of card is 4

The total no. of queen in deck of card is 4.

The total no. of ace in  deck of card is 4.

The total no. of jack in deck of card is 4.

Therefore, the number of favorable outcomes is 4+4+4+4= 16

Now, putting values in the above stated formula of probability, we get:

Probability= 16/52=4/13

Therefore, the probability of pulling a King, Ace, Jack of Clubs, or Queen of Diamonds from a 52-card standard deck that has been properly shuffled is 4/13.

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The probabilities, using the hypergeometric distribution, are given as follows:

i) Two wear the same color: 37/105: 0.35238 = 37/105.

ii) At least 2 wear red: 0.4461.

The mass probability formula is presented as follows:

[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}C_{N-k,n-x}}{C_{N,n}}[/tex]

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

The parameters are presented as follows:

The probability of two red is given as follows:

[tex]P(X = 2) = h(2,15,2,7) = \frac{C_{7,2}C_{8,0}}{C_{15,2}} = 0.2[/tex]

The probability of two green is given as follows:

[tex]P(X = 2) = h(2,15,2,6) = \frac{C_{6,2}C_{9,0}}{C_{15,2}} = 0.14286[/tex]

The probability of two white is given as follows:

[tex]P(X = 2) = h(2,15,2,2) = \frac{C_{2,2}C_{13,0}}{C_{15,2}} = 0.00952[/tex]

Then the probability of two wearing the same color is given as follows:

0.2 + 0.14286 + 0.00952 = 0.35238 = 37/105.

The probability that out of 3 people, at least 2 wear red, is given as follows:

[tex]P(X = 2) = h(2,15,3,7) = \frac{C_{7,2}C_{8,1}}{C_{15,3}} = 0.3692[/tex]

[tex]P(X = 3) = h(3,15,3,7) = \frac{C_{7,3}C_{8,0}}{C_{15,3}} = 0.0769[/tex]

Hence:

0.3692 + 0.0769 = 0.4461.

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Simple interest at a rate of 5% per year for five years on a principle of $5,000 has resulted in a total accrual of $6,250.00, which includes both the principal and interest.

To calculate simple interest, multiply the daily interest rate by the principle and the number of days between payments. Consumers that make on-time or early monthly loan payments benefit from simple interest. Most loans with simple interest rates are auto loans and short-term personal loans.

A = $6,250.00

I = A - P = $1,250.00

Formula: A = P(1 + rt)

First, convert R percent to r decimal, which is equal to 5%/100 or 0.05 per year.

Fixing our equation

A = 5000(1 + (0.05 × 5)) = 6250 \sA = $6,250.00

Simple interest at a rate of 5% per year for five years on a principle of $5,000 has resulted in a total accrual of $6,250.00, which includes both the principal and interest.

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When the area of the poster is 256 square inches, the measurements are 32 inch and 8 inch.

The quantity area indicates the extent of a region on a planar or curved surface. Surface area refers to the area of an open surface or the border of a three-dimensional object, whereas area of a plane region or plane area refers to the area of a form or planar lamina. The total space occupied by a flat (2-D) surface or the form of an item is defined as its area. The area is the region defined by an object's form. The area of a form is the space covered by a figure or any two-dimensional geometric shape in a plane.

Here,

let length be l and width be w.

l=3w+8

l*w=256

(3w+8)*w=256

3w²+8w=256

3w²+32w-24w-256=0

3w(w-8)+32(w-8)=0

(3w+32)(w-8)=0

w=-32/3, 8

w=8 inch

l=3*8+8

l=32 inch

The dimensions for the poster are 32 inch and 8 inch when area of the poster is 256 square inches.

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By solving the equation we get ,t = ± 7 using concept of square roots.

How to find the square roots ?

Square root, in mathematics, a factor of a number that, when multiplied by itself, gives the original number. For example, both 3 and –3 are square roots of 9.

For example, 2 is the square root of 4, and this is expressed as √4 = 2.

We know that every squared number has two square roots one is positive and another is negative.

In given que,

given condition is t squared minus 49 = 0

Form of equation is ax^ 2 = c.

given condition can also be written as t^2 - 49 = 0

                                                          i.e. t^2 = 49

where a = 1

x = t

c = 49

So, the square root are 7 and -7.

So, equation become t = ± 7.

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Answer:

  x = 15

Step-by-step explanation:

You have ∆UVW with angles U=(3x-10)°, V=(6x+5)°, and W=(4x-10)°, and you want to know the value of x.

The angle sum theorem tells you the sum of angles in a triangle is 180°.

  U +V +W = 180°

  (3x -10)° +(6x +5)° +(4x -10)° = 180°

  13x -15 = 180 . . . . . . . divide by °, collect terms

  13x = 195 . . . . . . . add 15

  x = 15 . . . . . . . divide by 13

The value of x is 15.

The options that represent binomial random variable  are;

A. Take a random sample of 30 tours and let L = the number of tours that result in a sale.

B. Take a random sample of 3 tours and let K = the number of tours that result in a sale.

There are 4 primary conditions for a random variable to be classified as binomial random variable and they are;

1. The number of observations n is fixed.

2. Each observation is independent.

3. Each observation represents one of two outcomes ("success" or "failure").

4. The probability of "success" p is the same for each outcome.

No, in this case, since 5% of home tours result in a sale, it therefore tells us that number of home tours is the independent variable while the amount of sales generated is the dependent variable.

From the above, we can access the given options and say that the last option is not a binomial random variable because the variable M is dependent and so does not satisfy one of the four conditions.

However, options A and B satisfy the 4 conditions and we say they are binomial random variables.

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Answer:

Step-by-step explanation:

The equation 5x-8+7y=y-6 is linear because it contains only terms with the variables x and y raised to the power of 1. In a linear equation, the highest power of any variable is 1. Nonlinear equations contain exponents that are higher than 1 on one or more variables.

The equation of the function described as;  y = 7 sin ( 4x + π/2 ) + 3

The general equation of the sine curve can be written as;

y = a sin ( nx + α ) + b

where : a is the amplitude, n = 2π/period, b = shift in the direction of y

            α°= shift in the direction of x

We are Given period = π/2 the maximum value is 10, the minimum value is −4 and y-intercept of 10.

 Thus,

a = (maximum - minimum)/2 = (10 - -4)/2

a = 7

 n = 2π/period = 2π/(π/2)

n = 4

 b = maximum - a = 10 - 7

b= 3

To find α as y-intercept = 10

y = 10 at x = 0

Substitute in the general function;

y = a sin ( nx + α ) + b

10 = 7 sin ( 4*0 + α ) + 3

Thus, we have;

sin α = 1

α = π/2

So, the equation of the function described is;

 y = 7 sin ( 4x + π/2 ) + 3

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