A tank contains 40 lb of salt dissolved in 500 gallons of water. A brine solution is pumped into the tank at a rate of 5 gal/min; it mixes with the solution there, and then the mixture is pumped out at a rate of 5 gal/min. Determine A(t), the amount of salt in the tank at time t, if the concentration of salt in the inflow is variable and given by cin(t)

Answer:

4

Step-by-step explanation:

1, 3, 4, 6, 2, 4, 5, 6, 2, 3, 1, 4, 0, 4, 4, 4, 8, 9, 7, 4

Arrange the numbers from smallest to largest

0,1, 1,2,2, 3,3, 4, 4,4,4,4,4 , 4, 5, 6, 6,   7, 8, 9,

There are 20 numbers

The middle number is between 10 and 11

0,1, 1,2,2, 3,3, 4, 4,4   ,4,4,4 , 4, 5, 6, 6,   7, 8, 9,

The median is 4

Solution,

Arranging the data in ascending order:

0,1,1,2,2,3,3,4,4,4,4,4,4,4,5,6,6,7,8,9

N(total number of items)= 20

Now,

Median:

[tex] (\frac{n + 1}{2)} ) ^{th \: item} \\ = (\frac{20 + 1}{2} ) ^{th \: item} \\ = \frac{21}{2} \\ = 10.5 \: th \: \: item[/tex]

Again,

Median:

[tex] \frac{10 \: th \: item + 11 \: th \: item}{2} \\ = \frac{4 + 4}{2} \\ = \frac{8}{2} \\ = 4[/tex]

Answer:

the answer is 9! ÷ (4! * 2! * 2!)

Step-by-step explanation:

The different words that can be formed with the letters AAAABBCCD will be 3780.

What is permutation?

The permutation is a mathematical calculation of the number of ways a particular set can be arranged, where the order of the arrangement matters.

We have,

AAAABBCCD

i.e.

Total number of letters = 9

Letter A repeated = 4 times

Letter B repeated = 2 times

Letter C repeated = 2 times

Now,

Using the permutation formula,

Permutation (ⁿPr) = n! / r!

So,

Number of ways = 9! / [ 4! × 2! × 2!] = [9 × 8 × 7 × 6 × 5 × 4!] / [ 4! × 2! × 2!] = 3780

Hence we can say that the different words that can be formed with the letters AAAABBCCD will be 3780.

To learn more about Permutation  click here,

https://brainly.com/question/1216161

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Answer:

There are 50 large boxes.

Step-by-step explanation:

First, "boxes of two sizes" means we can assign variables:

  Let x = number of large boxes

       y = number of small boxes

 "There are 115 boxes in all"    means    x + y = 115      [eq1]

Now, the pounds for each kind of box is:

    (pounds per box)*(number of boxes)

So,

  pounds for large boxes     +    pounds for small boxes      =    4125 pounds

                 "the truck is carrying a total of 4125 pounds in boxes"

        (50)*(x)                   +              (25)*(y)                  = 4125    [eq2]

It is important to find two equations so we can solve for two variables.

Solve for one of the variables in eq1 then replace (substitute) the expression for that variable in eq2.  Let's solve for x:

   x = 115 - y          [from eq1]

    50(115-y) + 25y = 4125             [from eq2]

     5750 - 50y  + 25y = 4125           [distribute]

     5750 - 25y = 4125

      -25y = -1625

         y = 65             [divide both sides by (-25)]

 There are 65 small boxes.

Put that value into either equation (now, which is easier?) to solve for x:

  x = 115 - y

  x = 115 - 65

  x = 50

Answer:

[tex]\huge\boxed{x=\sqrt{66}}[/tex]

Step-by-step explanation:

ΔADC and ΔABD are similar (AAA)

Therefore the cooresponging sides are in proportion:

[tex]\dfrac{AD}{AC}=\dfrac{AB}{AD}[/tex]

Substitute

[tex]AD=x;\ AC=6+5=11;\ AB=6[/tex]

[tex]\dfrac{x}{11}=\dfrac{6}{x}[/tex]          cross multiply

[tex](x)(x)=(11)(6)\\\\x^2=66\to x=\sqrt{66}[/tex]

Answer:

False, there are actually infinite solutions as these are parallel lines.

Step-by-step explanation:

Answer:

Height at t = 1 sec is 1144 ft

Step-by-step explanation:

Given:

Initial height of object = 1160 feet

Height of object after t seconds is given by the polynomial:

[tex]- 16t ^2+ 1160[/tex]

Let [tex]h(t)=- 16t ^2+ 1160[/tex]

Let us analyze the given equation once.

[tex]t^2[/tex] will always be positive.

and coefficient of [tex]t^2[/tex] is [tex]-16[/tex] i.e. negative value.

It means something is subtracted from 1160 ft (i.e. the initial height).

So, height will keep on decreasing with increasing value of t.

Also, given that the object is dropped from the top of a tower.

To find:

Height of object at t = 1 sec.

OR

[tex]h (1)[/tex] = ?

Solution:

Let us put t = 1 in the given equation: [tex]h(t)=- 16t ^2+ 1160[/tex]

[tex]h(1)=- 16\times 1 ^2+ 1160\\\Rightarrow h(1) = -16 + 1160\\\Rightarrow h(1) = 1144\ ft[/tex]

So, height of object at t = 1 sec is 1144 ft.

Answer:

TRUE

Step-by-step explanation:

The circumcenter of a triangle is the center of the only circle that can be circumscribed about it

Answer:

False

Step-by-step explanation:

Answer:

The answer is explained below

Step-by-step explanation:

Given that, the equation H*x = c is inconsistent for some c in R^n, we can say that the equation A*x = b has at least one solution for each b in R^n of IMT (Inverse Matrix Theorem) is not fulfilled.

Thanks to this we can say that by equivalence of theorem statement, the equation H*x = 0 will not have only the trivial solution. It will have non-trivial solutions too.

Answer:

x = 7

Step-by-step explanation:

This problem can be solved using angular bisector theorem.

It states that if any angle of triangle is bisected by a line , then that line

divides the opposite side of that angle in same proportion as that of two other sides which contain the angle.

__________________________________

Here one angle is is divided into parts theta

Thus,

using angular bisector theorem

14/21 = 6/3x-12

=> 14(3x-12) = 21*6

=> 3x-12 = 21*6/14 = 9

=> 3x = 12+9 = 21

=> x = 21/3 = 7

Thus, x = 7

Answer:

2/7

Step-by-step explanation:

The numbers greater than 7 or less than 3 are 2 and 8.

2 numbers out of 7.

P(greater than 7 or less than 3) = 2/7

Answer:

2/7

Step-by-step explanation:

There are a total of 7 sample spaces also known as 2,3,4,5,6,7,8. Now we have to find a number greater than 7 and less than 3. 2 is less than 3, and 8 is greater than 7, so two numbers are selected. This would become 2/7 because out of all of the 7 outcomes, only two are selected.

Answer:

Domain is  

{

x

∈

R

;

x

≠

−

5

}

Range is  

{

y

∈

R

;

y

≠

0

}

Step-by-step explanation:

Explanation:

Domain: Denominator should not be  

0

∴

x

+

5

≠

0

or

x

≠

−

5

Domain is any real value except  

x

=

−

5

or  

{

x

∈

R

;

x

≠

−

5

}

Range is any real value except  

y

=

0

or  

{

y

∈

R

;

y

≠

0

}

graph{1/(x+5) [-10, 10, -5, 5]}

Answer:

24 sixths in 4 and 3 two-thirds

Step-by-step explanation:

6=24 sixths in 4

Answer:

24 sixth's are in 4 and 3 two-third's are in 2

Step-by-step explanation:

4 ÷ 1/6 = 4 * 6 = 24

2 ÷ 2/3 = 2 * 3/2 = 3

Step-by-step explanation:

if there is any confusion then again ask me always with you

Answer:

d = 125

Step-by-step explanation:

E2020

pls mark Brainliest

Answer:

3 packs of barrettes and 4 packs of ribbons.

Step-by-step explanation:

All we need to do here is to find the least common multiple between 12 and 9.

We can factor both of these numbers to do so.

12: 3*4: 3*2*2

9: 3*3

We can cancel out one 3 (since it appears in both prime factorizations) and multiply what we have left to find the LCM.

2*2*3*3=36

This means that she will be making 36 clips/needs 36 of each item.

36/12=3

3 packs of barretes.

36/9=4

4 packs of ribbons.

Answer:

2699

Step-by-step explanation:

you do all the multiplication first

500×6= 3000

5 ×50 = 250

so it becomes

3000-51-250 = 2699

Answer:

2699

Step-by-step explanation:

Answer:

40

Step-by-step explanation:

An isosceles triangle is a triangle that has 2 congruent/equal sides and 2 congruent angles.

Side AB and side BC are the same length (the red tick marks shows that the sides are congruent)

Since they are the same length, you can set them equal to each other

Side AB = Side BC

x + 17 = 2x - 6        Subtract x on both sides

17 = x - 6       Add 6 on both sides

23 = x

Now that you know "x", you can find the length of Side BC:

2x - 6      Plug in 23 for "x"

2(23) - 6

46 - 6 = 40

Answer:

Yes, the answer is C! (40)

Answer:

a. The volume of Pyramid A is double that of Pyramid B.

b. The new volume of B is equal to the volume of A.

Step-by-step explanation:

The base of pyramid A is a rectangle with length 10 meters and width 20 meters.

The base of pyramid B is a square of side length 10 meter.

Both pyramids have the same height, h.

The volume of a pyramid is given as:

V = lwh / 3

where l = length

w = width

h = height

The volume of Pyramid A is:

V = (10 * 20 * h) / 3 = 66.7h cubic metres

The volume of Pyramid B is:

V = (10 * 10 * h) / 3 = 33.3h cubic metres

By comparing their values, the volume of Pyramid A is double that of Pyramid B.

If the height of B increases to 2h, its new volume is:

V = (10 * 10 * 2h) / 3 = 66.7h cubic metres

The new volume of B is equal to the volume of A.

Answer:

B

Step-by-step explanation:

The answer is B because in order for the square root of a number to be equal to another number, the answer squared should be the number under the square root.

B. [tex](-4)^2\neq -16[/tex].

Hope this helps.

Answer:

the answer will be D

Step-by-step explanation:

Answer:

[tex]2169.67-2.624\frac{48.72}{\sqrt{15}}=2136.66[/tex]    

[tex]2169.67+2.624\frac{48.72}{\sqrt{15}}=2202.68[/tex]    

And the confidence interval would be given by (2137, 2203)

Step-by-step explanation:

2051 ,2061 ,2162 ,2167 , 2169 ,2171 , 2180 , 2183 , 2186 , 2195 , 2196 , 2198 , 2205 , 2210  ,2211

We can calculate the mean and deviation with these formulas:

[tex]\bar X= \sum_{i=1}^n \frac{x_i}{n}[/tex] (2)  

[tex]s=\sqrt{\frac{\sum_{i=1}^n (x_i-\bar X)}{n-1}}[/tex] (3)  

And we got:

[tex]\bar X=2169.67[/tex] represent the sample mean for the sample  

[tex]\mu[/tex] population mean

s=48.72 represent the sample standard deviation

n=15 represent the sample size  

Confidence interval

The confidence interval for the mean is given by the following formula:

[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]   (1)

The degrees of freedom are given by:

[tex]df=n-1=15-1=14[/tex]

Since the Confidence is 0.98 or 98%, the significance is [tex]\alpha=0.02[/tex] and [tex]\alpha/2 =0.01[/tex], and using excel we calculate the critical value [tex]t_{\alpha/2}=2.624[/tex]

Now we have everything in order to replace into formula (1):

[tex]2169.67-2.624\frac{48.72}{\sqrt{15}}=2136.66[/tex]    

[tex]2169.67+2.624\frac{48.72}{\sqrt{15}}=2202.68[/tex]    

And the confidence interval would be given by (2137, 2203)

Answer: 151

Step-by-step explanation:

if prior population proportion is unknown , then the formula is used to find the sample size :

[tex]n=0.25(\frac{z_{\alpha/2}}{E})^2[/tex]

, where [tex]z_{\alpha/2}[/tex] = Two tailed critical value for significance level of [tex]\alpha.[/tex]

E = Margin of error.

Given : margin of error = 8%= .08

For 95% confidence level , two tailed critical value = 1.96

Now, the required sample size :

[tex]n=0.25(\frac{1.96}{0.08})^2\\\\=0.25(24.5)^2\\\\=150.0625\approx151[/tex]

Hence, the size of the sample needed = 151.

Answer:

Symmetric with respect to the polar axis in agreement with the second answer listed.

Step-by-step explanation:

This is the shape of a cardioid  [tex]14\,(1+cos(\theta))[/tex]  it contains the function cosine of the angle so it must be symmetric with respect to the polar axis, since the cosine function is also symmetric for positive and negative values of the angle.

Answer: (3y - 10)*2÷4

Step-by-step explanation:

Because 10 less than 3 times a number, y, is done first, it is in parenthesis.  The 3 is there to represent the "three times" and the -10 is there to represent the "ten less".  The *2 is there to represent the "multiplied by two" and the ÷4 is there to represent the "divided by 4"

Hope it helps, and tyvm <3

Answer:

[tex]\displaystyle \frac{2(3y - 10)}{4}[/tex]

Step-by-step explanation:

10 less than 3 times y.

The variable y is multiplied by 3, 10 is subtracted from 3 × y.

The result 3y - 10 is then multiplied by 2.

2(3y - 10) is then divided by 4.

Answer:

$1850 per month

Step-by-step explanation

There are two types of chocolates that can be produced milk chocolate and strawberry covered chocolate. To find the profit we make following equation,

P = $2.25 SC + $2.50 WC

where SC is strawberry chocolate and WC is White milk chocolate.

The maximum production level can be 800 boxes per month and white chocolates can not exceed the 200 boxes per month so we assume making 600 boxes of Strawberry covered chocolates and 200 boxes of white chocolates.

Profit = 2.25 * 600 + 2.50 * 200

Profit = $1850

This is the maximum profit that can be earned after making combination of two types of chocolates.

Answer:

The amount in the account at 12% interest is $3400 and the amount in the second account at 7% interest is $2600

Step-by-step explanation:

Let x be the amount in the account at 12% interest

So, 6000-x is the amount in the second account at 7% interest

[tex]SI = \frac{P \times T \times R}{100}[/tex]

First account:[tex]SI=\frac{x \times 1 \times 12}{100}[/tex]

Second account : [tex]SI =\frac{(6000-x) \times 1 \times 7}{100}[/tex]

We are given that At the end of the first year he had earned $590 in interest.

So, [tex]\frac{x \times 1 \times 12}{100}+\frac{(6000-x) \times 1 \times 7}{100}=590\\x=3400[/tex]

So,the amount in the account at 12% interest is $3400

The amount in the second account at 7% interest =6000-x=6000-3400=2600

Hence the amount in the account at 12% interest is $3400 and the amount in the second account at 7% interest is $2600

Answer:

Just x

Step-by-step explanation:

√x times √x equals √x²

√x² = x

Answer:

3/10

Step-by-step explanation:

We have that the Armans last winter had 5/6 of a row of stacked logs and at the end of the winter he had 8/15 of the same row left, therefore:

Ambitious

First we have to do is that the denominator is the same.

in the case of 5/6 it would be 25/30

and for 8/15 it would be 16/30

Now if we can do the subtraction and it would be:

25/30 - 16/30 = 9/30 or what equals 3/10

3/10 was the amount of wood he burned in the winter

Answer:

D) 3/10 row

Step-by-step explanation:

Steps to solve:

9(d - 93) = -36d

~Distribute

9d - 837 = -36d

~Subtract 9d to both sides

-837 = -45d

~Divide -45 to both sides

18.6 = d

Best of Luck!