8) A school community had planned to reduce the number of grade 9 students per class room by constructing additional class rooms. However, they constructed 4 less rooms than they planned. As the result, the number of students per class 10 more than they planned. If there are 1200 grade nine students in the school, determine the current number of class rooms and the number of students per class.​

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Explanation:

PDF = probability density function

The given joint PDF is

[tex]f(x,y) = \begin{cases}ax \ \ \ \text{ if } 1 \le x \le y \le 2\\0 \ \ \ \ \ \text{ otherwise}\end{cases}[/tex]

Let's focus on the [tex]1 \le x \le y \le 2[/tex]. Specifically the x term for now. Erasing out the y term, we have the inequality [tex]1 \le x \le 2[/tex] which says x is between 1 and 2, inclusive. We have almost the same story for y, but there's another condition attached to it: y must also be equal to or larger than x.

So let's say x = 1.5. This would mean [tex]1.5 \le y \le 2[/tex]. As another example, x = 1.7  leads to [tex]1.7 \le y \le 2[/tex]. In general, we would say [tex]x \le y \le 2[/tex] where x is between 1 and 2.

As x gets bigger, the range of possible y values gets smaller. If x = 2, then y has no choice but to be 2 as well.

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Based on that, we'll have a double integral that looks like this:

[tex]\displaystyle V = \int_{1}^{2}\int_{x}^{2}f(x,y)dydx\\\\[/tex]

The outer integral handles the x terms that range from 1 to 2, describing [tex]1 \le x \le 2[/tex]. Note the dx on the outside. The order of the dy and dx matters.

On the inside, we have the integral for dy ranging from x to 2 to describe the interval [tex]x \le y \le 2[/tex]

To have f(x,y) be a PDF, the volume under the f(x,y) surface must be 1, where the volume is based on the bounds set up. So we must have V = 1. We'll use this later.

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Let's simplify the double integral.

We'll start by computing the inner integral with respect to y.

[tex]\displaystyle V = \int_{1}^{2}\int_{x}^{2}f(x,y)dydx\\\\\displaystyle V = \int_{1}^{2}\int_{x}^{2}\left(ax\right)dydx\\\\\displaystyle V = \int_{1}^{2}\left(axy\Bigg|_{x}^{2}\right)dx\\\\\displaystyle V = \int_{1}^{2}\left(ax(2) - ax(x)\right)dx\\\\\displaystyle V = \int_{1}^{2}\left(2ax - ax^2\right)dx\\\\[/tex]

Then we'll finish it off by integrating with respect to x.

[tex]\displaystyle V = \int_{1}^{2}\left(2ax - ax^2\right)dx\\\\\displaystyle V = \left(ax^2 - \frac{1}{3}ax^3\right)\Bigg|_{1}^{2}\\\\\displaystyle V = \left(a(2)^2 - \frac{1}{3}a(2)^3\right) - \left(a(1)^2 - \frac{1}{3}a(1)^3\right)\\\\\displaystyle V = \left(4a - \frac{8}{3}a\right)-\left(a - \frac{1}{3}a\right)\\\\[/tex]

[tex]\displaystyle V = 4a - \frac{8}{3}a-a + \frac{1}{3}a\\\\\displaystyle V = 3a - \frac{8}{3}a + \frac{1}{3}a\\\\\displaystyle V = \frac{9}{3}a - \frac{8}{3}a + \frac{1}{3}a\\\\\displaystyle V = \frac{9-8+1}{3}a\\\\\displaystyle V = \frac{2}{3}a\\\\[/tex]

Side note: We don't have to worry about the "plus C" integration constant when working with definite integrals.

Recall that V = 1. So,

[tex]\displaystyle V = \frac{2}{3}a\\\\\displaystyle \frac{2}{3}a = 1\\\\\displaystyle a = \frac{3}{2} = 1.5\\\\[/tex]

a = 3/2 is the final answer.

Answer:

125 cm3

Step-by-step explanation:

V = l * w * h

V = 5 * 5 * 5

V = 125 cm3

Answer:

125 cm^3

Step-by-step explanation:

To calculate the area of a cube, just do the side length to the power of 3.

5^3=125

Answer:

142

Step-by-step explanation:

Median is the MID Number

The equilibrium price of the commodity at the given demand and supply is 1,000.

The given parameters:

The equilibrium price of the commodity is calculated as follows;

At equilibrium price, the demand curve and supply curve cross each other.

[tex]QS= QD\\\\15,000 +2P = 20,000 - 3P\\\\2P+3P = 20,000 - 15,000\\\\5P = 5,000[/tex]

[tex]P = \frac{5,000}{5} \\\\P = 1,000[/tex]

Thus, the equilibrium price of the commodity is 1,000.

The complete question is below;

Determine the equilibrium price, if QD = 20000 -3P  and QS = 15000 +2P.

Learn more about equilibrium price here: https://brainly.com/question/22569960

Answer:

I dont know sorry

next time

Answer:

                                 pop

                                             yes                   no             total

country            yes                  11                      38              49

                        no                       43                     8                51

                         total                54                     46               100

Hope you understand this haha

The answer is in the file. Hope it helps.

Answer:

yes less than a min

Step-by-step explanation:

Answer:

A is correct

Step-by-step explanation:

perimeter is twice the sum of the two adjacent sides

p = 2(x + (2x³ - 3x + 4))

p = 2(2x³ - 2x + 4)

p = 4x³ - 4x + 8

5x - 8 = 3x + 12

- 3x -3x

You have to subtract them both.

2x - 8 = 12

Answer:

Step-by-step explanation:

100(9801 - 8910)/8910 = 10%

Answer:

Step-by-step explanation:

You may find this easier if you distribute the minus sign first.

2a^2 -3ab +5b^2 -a^2 +2ab -3b^2

  = (2 -1)a^2 +(-3+2)ab +(5 -3)b^2

  = a^2 -ab +2b^2 . . . . . matches choice D

__

6x -3 -2x +2

  = (6 -2)x +(-3 +2)

  = 4x -1 . . . . . matches choice B

Yes, that is correct because 2 and 4 can both go into 8 making it a factor of the number you are talking about. ANSWER: That is true

Answer:

11

Step-by-step explanation:

Answer:

A. distributive

Step-by-step explanation:

You would multiply the 9 with the x to get 9x, and then you would multiply the 9 with the negative -5 to get 9x-45.

is it like mutiplying and dividing

The area of the rectangle that has side lengths of 7 yards and 3 yards is 21 square yards.

Rectangles are quadrilaterals having four equal vertices and parallel sides that are equal to one another.

To find the area of the rectangle that has side lengths of 7 yards and 3 yards, use the formula as described below,

the area of the rectangle = length x width of the rectangle.

Substituting the value of the side lengths to the formula,

The area of the rectangle = 7 x 3

The area of the rectangle = 21 square yards.

Therefore, the area is 21 square yards.

To learn more about the rectangular;

brainly.com/question/21416050

#SPJ7

Answer:

Slide UP 2

Step-by-step explanation:

In the equation,

f(x) = 9|x+1| + 2

There are three transformations of the parent function f(x)=|x| (this is the simplest form of this function, it's a v-shaped graph)

The 9 in front will vertically stretch the graph and make it look like a "skinny" v-shaped graph.

The +1 in close to the x inside the absolute value bars |x+1| will shift (slide) the graph to the left (it's the opposite of what you might think-- 'plus' shifts the graph left and 'minus' shifts the graph right)

The +2 at the end is the transformation you're looking for. It slides the graph as you would expect UP 2 units. If it was a minus it would shift the graph down instead.

Step-by-step explanation:

19. 4x² - 13x + 3

4x² - 1x - 12x + 3

x(4x - 1) -3(4x - 1)

x-3 4x-1

Answer:

The slope of the one of the top is -1/4

The slope of the one on the bottom is 1/6

Step-by-step explanation:

The one on the top goes down by 1 (negative) and goes 4 to the right (positive), which can be written as -1/4, which is the slope.

The one on the bottom goes up by 1 (positive) and goes to the right by 6 (positive), which can be written as 1/6, which is is the slope.

Explanation:-

We have given measure of angles of the triangle are in ratio 4 : 7 : 9 and here we need to find the measure of largest angle of a ∆.

Let, the three angles of a triangle be 4x, 7x, 9x.

We know that, Sum of all angles of a triangle is 180°.

4x + 7x + 9x = 180°

⇛20x = 180°

⇛x = 180°:20

⇛x = 9°

Now, finding largest angle by putting the value of “x”

Hence ,the measure of largest angle is 81°.

also read similar questions:The ratio of the measures of the three angles in a triangle is 2:9:4. Find the measures of the angels.....

https://brainly.com/question/12057538?referrer

The ratio of the measures of the angles of a triangle is 4:6:8. Find the measure of the largest angle. Largest angle?....

https://brainly.com/question/16940866?referrer

Answer:

y=1/2x-8

Step-by-step explanation:

m=(y2-y1)/(x2-x1)

m=(-5-(-4))/(6-8)

m=(-5+4)/-2

m=-1/-2

m=1/2

y-y1=m(x-x1)

y-(-4)=1/2(x-8)

y+4=1/2(x-8)

y=1/2x-8/2-4

y=1/2x-4-4

y=1/2x-8

Answer: Yes (2,-1) is the solution for those systems.

becausee...

1. 3(2) - (-1) = 7

     6 + 1 = 7

     7 = 7

2. 2(2) + 3(-1) = 1

      4 - 3 = 1

      1 = 1

Hope this helps :)

Answer:

Yes the point (2,-1) is a solution of the system: 3x - y = 7 2x + 3y = 1

Step-by-step explanation:

(2,-1) = x = 2, y = -1

Now lets put these values in the given expressions

3x - y = 7

3 × 2 - (-1)

6 + 1

= 7 THIS EQUATION IS THE SOLUTION

2x + 3y = 1

2 × 2 + 3 × (-1)

4 - 3

= 1 THIS EQUATION IS THE SOLUTION

Answer:

3

Step-by-step explanation:

Answer:

24/2

Step-by-step explanation:

Answer:

2 or more so it's be like 3 I guess he doesn't have the right for the tiger and in the heights block he it is a great game and to

[tex]\\ \tt\bull\rightarrowtail h(x)=1/5(x^2-6)-8[/tex]

[tex]\\ \tt\bull\rightarrowtail h(4)[/tex]

[tex]\\ \tt\bull\rightarrowtail 1/5(4^2-6)-8[/tex]

[tex]\\ \tt\bull\rightarrowtail 1/5(16-6)-8[/tex]

[tex]\\ \tt\bull\rightarrowtail 10/5-8[/tex]

[tex]\\ \tt\bull\rightarrowtail 2-8[/tex]

[tex]\\ \tt\bull\rightarrowtail -6[/tex]

Answer:

112.81 miles

Step-by-step explanation:

304.6 divided by 2.7

Step-by-step explanation:

Male ratio: 204:306 = 2:3 (66%)

Female ratio: 180:420 = 3:7 (42%)

Hope that helps

Answer:

both are non smokers is 0.48.

Raise [tex]6[/tex] to the second power, [tex]6^{2}[/tex], the subtract r from the result, that should be [tex]6^{2} - r[/tex], since we are not to simplify the expression, that's the answer.