There are 40 students in your class of which 23 are boys. What fraction of the students are girls?​

Answer:

A. (A) Yes

B. (A) Yes

C. (B) No

Step-by-step explanation:

A is Categorical because it is not based on numbers.

B is Categorical because it is not based on numbers.

C is Not Categorical because it is based on numbers.

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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:

113

Step-by-step explanation:

The supplement of angle 3 is congruent to 67, because they are corresponding angles. After you subtract the supplement from 180, you should get angle 3

180-67=113

Answer:

∠3 measures 113°

Step-by-step explanation:

These are consecutive interior angles. It's difficult to explain in words because none of the lines are marked in any way, but I marked the angles in the attached image. Because both downward facing lines are parallel, both sets of corresponding red and blue angles are congruent.

∠3 corresponds to the angle supplementary to the 67° angle. Supplementary angles add up to 180°, so ∠3 and 67° also have to add up to 180°. Hopefully my image makes that a little more clear.

[tex]x+67=180\\x=113[/tex]

∠3 measures 113°

Answer:

32.5

Step-by-step explanation:

Using fractions, it is found that of the students that went camping, [tex]\mathbf{\frac{23}{84}}[/tex] were at Lake Camp.

The students who went camping are divided according to the following fractions:

The sum of all these fractions is 100% = 1, hence:

[tex]\frac{1}{7} + \frac{1}{3} + \frac{1}{4} + x = 1[/tex]

[tex]\frac{12 + 28 + 21 + 84x}{84} = 1[/tex]

[tex]84x + 61 = 84[/tex]

[tex]84x = 23[/tex]

[tex]x = \frac{23}{84}[/tex]

Of the students that went camping, [tex]\mathbf{\frac{23}{84}}[/tex] were at Lake Camp.

A similar problem is given at https://brainly.com/question/24372153

Answer:

7

Step-by-step explanation:

12-(-3)-2(4)

12-(-3)-8

15-8=7

Answer:

[tex]\boxed{\sf D)\:-24a^3b^7}[/tex]

Step-by-step explanation:

[tex]\sf (3a^2b^4)(-8ab^3)[/tex]

We'll use rule of exponents to simplify expression.

[tex]\sf 3^1a^2b^4(-8)^1a^1b^3[/tex]

Now, use the commutative property of multiplication.

[tex]\sf 3^1(-8)^1a^2a^2b^4b^4[/tex]

In order to multiply power of the same base, we add their exponents.

[tex]\sf 3^2(-8)^1a^{2+1}b^{4+3}[/tex]

→ Add exponents:

[tex]\sf 3^1(-8)^1a^3b^7[/tex]

→ Multiply 3* -8

[tex]\sf -24a^3b^7[/tex]

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Answer:

Down, Down, Right, Right, diagonal left, up, right

Step-by-step explanation:

Not gonna do every equation here tho lol

Answer:

i guess it's will be C

Step-by-step explanation:

Answer:

f(-18) = -5

Step-by-step explanation:

Substitute−18forxiny=

1/3 x+1:

y= 1/3x+1

y= 1/3(−18)+1

y=−5(Simplify both sides of the equation)

Answer:

The first recipe - 3/4 tsp of salt in 1 cup of water

Step-by-step explanation:

1st recipe Salt per cup = 3/4 tsp / 1 cup = 3/4 tsp salt

2nd recipe Salt per cup = 1 tsp / 2 cups = 1/2 tsp salt

3/4 tsp > 1/2 tsp, hence the first recipe is saltier

Answer:

AOB forms must be collected every time a beneficiary fills a Medicare part b prescription

Answer:

12

Step-by-step explanation:

You do 6+6, or 2+2+2+2+2+2=12

Answer:

so you just use the equation to get the formula and extract the common denominator

Step-by-step explanation:

because i said so

Step-by-step explanation:

several possibilities to solve this.

let's start with subtracting the second equation from the first

-x + 2y - z = 0

- -x - y +2z = 0

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0 3y - 3z = 0

y - z = 0

y = z

now we use this in e.g. the first equation :

-x + 2z - z = 0

-x + z = 0

z = x (therefore, also x = y)

now we use this in the third equation :

2x - x = 8

x = 8 = y = z

Answer:W= B-3 or 3=B-W

Step-by-step explanation:

100 mph per hour

Step-by-step explanation:

solution

speed of auto mobile=50mph

distance already traveled when the airplane took out in pursuit=200miles

time taken to overtake the car=4 hours

Now,

let the speed of airplane be X

X=50×4+200

or,X=200+200

or,X=400

or, X=400÷4

Therefore, X=100

Answer:

1.) Smith

2.) Johnson

Answer:

Step-by-step explanation:

[tex]\tan \theta = \dfrac{\text{Opposite side}}{\text{Adjacent side}} = \dfrac{16}{12}[/tex]

Answer:

The answer is y= 100 +15x

Step-by-step explanation:

You start with a service fee of $100

$15 per hour

x because the amount of hours can vary

y which is the total cost

y= 100+ 15x

The equation of the line is:

[tex]y=\frac{-1}{2}x-26[/tex]

The point-slope equation of a line is given as:

[tex]y-y_1=m(x-x_1)[/tex]

where m represents the slope, and is calculated as:

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

For the line passing through the points (-32, - 10) and (-74, 11)

[tex]x_1=-32, y_1=-10, x_2=-74, y_2=11[/tex]

Substitute these points into the slope formula to get the slope of the line

[tex]m=\frac{11-(-10)}{-74-(-32)} \\\\m=\frac{11+10}{-74+32} \\\\m=\frac{21}{-42} \\\\m=\frac{-1}{2}[/tex]

Substitute [tex]m=\frac{-1}{2}, x_1=-32, y_1=-10[/tex] into the line equation

[tex]y-(-10)=\frac{-1}{2}(x-(-32))\\\\y+10=\frac{-1}{2}x-16\\\\y= \frac{-1}{2}x-16-10\\\\y=\frac{-1}{2}x-26[/tex]

The equation of the line is:

[tex]y=\frac{-1}{2}x-26[/tex]

Learn more on equation of a line here: https://brainly.com/question/13763238

The volume of the storage room is the amount of space in the storage room, and it is 720 cubic feet

The dimensions are given as:

[tex]Width = 6ft[/tex]

[tex]Depth = 10ft[/tex]

[tex]Height = 12ft[/tex]

The volume of the storage room is the product of the dimensions.

So, we have:

[tex]Volume= Width \times Depth \times Height[/tex]

Substitute values for Width, Depth and Height

[tex]Volume= 6ft \times 10ft \times 12ft[/tex]

Multiply the dimensions

[tex]Volume= 720ft^3[/tex]

Hence, the volume of the storage room is 720 cubic feet

Read more about volumes at:

https://brainly.in/question/2593668

Answer:

-1/2 + i/10 sqrt(55)  , -1/2 - i/10 sqrt(55)

Step-by-step explanation:

5x^2+5x+4=0

a=5  b= 5  c=4

Using the quadratic formula

-b ± sqrt( b^2 -4ac)

---------------------------------

  2a

-5 ± sqrt( 5^2 - 4(5)(4))

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2(5)

-5±sqrt( 25 - 80)

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10

-5± sqrt(-55)

--------------------------

10

-5/10  ± 1/10  i sqrt(55)

-1/2 + i/10 sqrt(55)  and -1/2 - i/10 sqrt(55)

Answer:

x= -5 ± i√55 / 10

Step-by-step explanation:

hope i helped

Answer:

Step-by-step explanation:

An example of one fraction that does NOT terminate is 2/3.

2/3 = 0.666666666666666 ....  That's the easy way to tackle the problem. Pick out the ones that don't terminate.

5/7 is the other one. It does not terminate either. It has 6 digits in a block that keeps on repeating itself forever.

5/7 = .571428 571428 which goes on forever.

So the two that do terminate are

3/2 which = 1.5

3/4 which = 0.75

Answer:

18/100 or 9/50

Step-by-step explanation:

First, put 0.18 over 100 because there are 2 digits in the decimal, so you convert it to 18/100. Then, simplify it, and because the GCF is 2, divide the numerator and denominator. The final fraction ins 9/50.

Answer:

hello which grade question i

Answer:

half-class

Step-by-step explanation:

Answer:

42.86%

Step-by-step explanation:

Event = Girl

Therare 6 girls and 8 boys, which are thus 6+8 =14 students in total and thus there are 14 possible out comes.

# of possible outcomes = 14

There are 6 girls in the class and thus there are 6 favorable outcomes.

# of favorable outcomes = 6

The probability is the number of favorable outcomes divided by the number of possible outcomes.

P(Girl) = # of favorable outcomes

            # of possible outcomes

= [tex]\frac{6}{14}[/tex]

= [tex]\frac{3}{7}[/tex]

≈ 0.4286

= 42.86%

Result

[tex]\frac{3}{7}[/tex] ≈ 0.4286 = 42.86%