How do I solve problem 7?

Answer:

10 girls

11 boys

Step-by-step explanation:

set up a system of equations:

b represents boys, g represents girls

b+g=21           (since there is a total of 21 students)

11b+13g=251   (since each boy has 11 pockets, each girl has 13, total of 251)

i chose the method of substitution, so i solved the first equation to get

b=21-g

then i substitute 21-g for b in the second equation, and solve:

11(21-g)+13g=251

231-11g+13g=251

2g+231=251

2g=20

g=10

then, i solved for boys (by choosing the top equation and substituting 10 for g, since we now know that g=10)

b+g=21

b+10=21

b=11

so there are 10 girls and 11 boys in this class

There are 10 girls and 11 boys in the class.

"It is a statement which consists of equal symbol between two mathematical expressions."

"It is a finite set of equations for which we find a common solution."

For given example,

Let 'x' be the number of girls and 'y' be the number of boys.

Each boy in a class has 11 pockets and each girl in the class has 13 pockets.

And in this class if all 21 students have a total of 251 pockets.

So, we have system of equations,

⇒ x + y =21                                 .......................(1)

⇒ 13x + 11y = 251                        .......................(2)

From equation (1),

x = 21 - y                                  ......................(3)

Substitute this value of 'x' in the equation (2),

⇒ 13(21 - y) + 11y = 251

⇒ 273 - 13y + 11y = 251

⇒ 273 -2y - 273 = 251 - 273

⇒ -2y = -22

⇒ y = -22 / -2

⇒ y = 11

This means, there are 11 boys in the class.

Substitute the value of 'y' in equation (3),

⇒ x = 21 - 11

⇒ x = 10

This means there are 10 girls in the class.

Therefore, there are 10 girls and 11 boys in the class.

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Answer: 112 degrees

Explanation:

By the alternate interior angles theorem, m<CAD=40 and m<ACD=28. The quadrilateral is divided into two triangles. The sum of the angles of a triangle is equal to 180 degrees. Now that you know the measurements of two out of the three angles, you can add them up and subtract them from 180.

180-(40+29)=112

Answer:

The space needle is 62.95 m tall.

Step-by-step explanation:

Given that,

The height of the shadow, h = 67 m

The angle of elevation  from the tip of the shadow to the top of the Space Needle is 70°.

We need to find the height of the space needle.

The shadow of space needle is hypotenuse of right angled triangle. Let the height of the space needle is x m. Using trigonometry,

[tex]\sin\theta=\dfrac{x}{h}\\\\x=h\times \sin\theta\\\\x=67\times \sin(70)\\\\x=62.95\ m[/tex]

So, the space needle is 62.95 m tall.

Answer:

1 + 2x

Step-by-step explanation:

3x + 1 - 6x + 4x + x ← collect like terms

= 1 + 2x

Sum of 3x, (1 - 6x), 4x and x is 2x + 1.

A summation, also called a sum, is the result of arithmetically adding numbers or quantities. A summation always contains a whole number of terms. There can be as few as two terms, or as many as a hundred, a thousand, or a million. Some summations contain infinitely many terms.

A sum is the result of an addition.

Sum is a way of putting all things together. The sum brings two or more numbers together to make a new total.

According to the question

We have to find the sum of 3x, (1 - 6x), 4x and x

A sum is the result of an addition.

Sum = 3x + (1 - 6x) + 4x + x

Sum = 3x + 1 -6x + 4x + x

Sum = 8x - 6x + 1

Sum = 2x + 1

Hence,

Sum of 3x, (1 - 6x), 4x and x is 2x + 1.

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Using combination, 5184 nine-digit numbers can be made using each of the digits 1 through 9 exactly once with the digits alternating between odd and even.

An arrangement of items in a specific order is referred to as a permutation. Here, the components of sets are arranged in a linear or sequential order. For instance, the set A=1,6 has a permutation of 2, which is 1,6,1. There is no other way to arrange the components of set A, as you can see.

If the first letter is even, there are 4 first digit possibilities (not 5 because it can't start with 0), 4 third digit possibilities, 3 fifth digit possibilities, etc., making the total 4!

If an odd number is the first letter, there will be 5!*4! different ones.

Add the two together now.

4*4!*4! + 5!*4!=5184

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On solving the provided question we cans ay thatVertical Angles: TZU, XZW Adjacent Angles: TZU, UZV are Vertical angle and adjacent angle.

What is Vertical angle and adjacent angle,?

Vertical angles are two angles that share the same vertex and are formed by two intersecting lines. They are congruent (i.e. have the same measure) and are opposite each other

Adjacent angles are two angles that share a common vertex and side, but do not overlap. They are also called "next to" or "sharing an arm" angles.

Fig 1:

Vertical Angles: NMJ, LMK

Adjacent Angles: NMJ, JMK

Fig 2:

Vertical Angles: DEA, CEB

Adjacent Angles: DEA, AEB

Fig 3:

Vertical Angles: LQM, PQN

Adjacent Angles: LQM, MQN

Fig 4:

Vertical Angles: TZU, XZW

Adjacent Angles: TZU, UZV

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Answer:

x ≈ 10.6

Step-by-step explanation:

using the cosine ratio in the right triangle

cos35°= [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{x}{13}[/tex] ( multiply both sides by 13 )

13 × cos35° = x , then

x ≈ 10.6 ( to the nearest tenth )

Answer:

130,a circle is 360 around so minus 230

The value of next two terms are,

⇒ 0 and - 60

A relation between a set of inputs having one output each is called a function.

Given that;

The values are,

⇒ f (1) = 120,

⇒ f (2) = 60

And, The function is,

⇒ f (n) = f (n - 1) + ___

For n ≥ 2

Now,

Since, The values are,

⇒ f (1) = 120,

⇒ f (2) = 60

And, The recursive formula is,

⇒ f (n) = f (n - 1) + b

For n ≥ 2

Substitute n = 2;

⇒ f (2) = f (2 - 1) + b

⇒ 60 = f (1) + b

⇒ 60 = 120 + b

⇒ b = 60 - 120

⇒ b = - 60

So, The recursive formula is,

⇒ f (n) = f (n - 1) - 60

Substitute n = 3;

⇒ f (3) = f (3 - 1) - 60

⇒ f (3) = f (2) - 60

⇒ f (3) = 60 - 60

⇒ f (3) = 0

Substitute n = 4;

⇒ f (4) = f (4 - 1) - 60

⇒ f (4) = f (3) - 60

⇒ f (4) = 0 - 60

⇒ f (4) = - 60

Thus, The next two term are 0 and - 60.

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The missing information, considering the volume of the cone and the cylinder, is given as follows:

The volume of a cylinder of radius r and height h is given as follows:

Vcy = πr²h.

The volume of a cone is one third that of the cylinder, hence:

Vco = πr²h/3.

At the second row, the volume of the cylinder is three times that of the cone, hence:

40π x 3 = 120π.

Considering the volume of the cylinder and the radius, the height is obtained as follows:

πr²h = 120π

9h = 120

h = 120/9

h = 13.3.

For the third row, we have that the base area is of 36π squared units, hence the radius is obtained as follows:

πr² = 36π

r = 6. (as the base is circular).

Hence the diameter is of 12 units, as the length of the diameter is twice that of the radius.

The volume of the cylinder is three times that of the radius, hence:

3 x 48π = 144π

Meaning that the height is then calculated as follows:

πr²h = 144π

36h = 144

h = 144/36

h = 4.

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For a trigonometric equation. Cos^2x=3sin^2x, the solution is mathematically given as x = π/6 + 2nπ.

Trigonometry is the study of angles and the angular connections of planar and three-dimensional shapes. Trigonometry is made up of trigonometric functions (also known as circle functions) such as cosecant, cosine, cotangent, secant, sine, and tangent.

Generally, the equation for the trigonometric equation is mathematically given as:

Cos^2x=3sin^2x

Therefore

1 - sin^2(x) = 3 sin^2(x)

1/4 = sin^2(x)

Hence introducing \pi

x = arcsin(1/2) + 2nπ  

x = π/6 + 2nπ

In conclusion,

x = π/6 + 2nπ

For a trigonometric equation. Cos^2x=3sin^2x, the solution is mathematically given as x = π/6 + 2nπ.

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Answer:

16

Step-by-step explanation:

8*2*1=16

Answer:

D

Step-by-step explanation:

Cuz is negative u need the bracket

Answer:

no lol

Step-by-step explanation:

Answer:

m DE=60°

Step-by-step explanation:

OR≅OS

in Δ STW,

SW=TW

TS=SW=TW

m∠TSW=60°

m DE= 60°

༄❁༄❁༄❁༄❁༄

hope it helps...

have a great day ! ! !

Answer:

The area of the rectangle ABCD is [tex]\frac{2}{5}[/tex] square units.

Step-by-step explanation:

From statement we have that rectangle ABCD is formed by the following points: [tex]A(x,y) = (2, 5), B(x,y) = \left(\frac{8}{3}, 5 \right), C(x,y) = \left(\frac{8}{3}, \frac{28}{5} \right), D(x,y) = \left(2, \frac{28}{5} \right)[/tex]. First, we calculate the length of each side by the Pythagorean Theorem:

[tex]AB = \sqrt{\left(\frac{8}{3}-2 \right)^{2}+ (5-5)^{2}}[/tex]

[tex]AB = \frac{2}{3}[/tex]

[tex]BC = \sqrt{\left(\frac{8}{3}-\frac{8}{3}\right)^{2}+\left(\frac{28}{5}-5\right)^{2} }[/tex]

[tex]BC = \frac{3}{5}[/tex]

[tex]CD = \sqrt{\left(2-\frac{8}{3} \right)^{2}+\left(\frac{28}{5}-\frac{28}{5} \right)^{2}}[/tex]

[tex]CD = \frac{2}{3}[/tex]

[tex]DA = \sqrt{\left(2-2\right)^{2}+\left(5-\frac{28}{5} \right)^{2}}[/tex]

[tex]BC = \frac{3}{5}[/tex]

Which satisfies all minimum characteristics for a rectangle. The area of the rectangle ABCD is the product of its base and its height, that is:

[tex]A = \left(\frac{2}{3}\right)\cdot \left(\frac{3}{5} \right)[/tex]

[tex]A = \frac{2}{5}[/tex]

The area of the rectangle ABCD is [tex]\frac{2}{5}[/tex] square units.

The angle of elevation of the coconut palm tree from me is [tex]38\x^{o}[/tex].

The angle of elevation is the angle created between the line of sight and the horizontal. The angle created is an angle of elevation if the line of sight is upward from the horizontal line.

the angle of elevation is defined as "the angle created between the horizontal line and the line of sight when an observer looks upwards." It is always higher than the observer and at a larger angle. When a person stares downward, they create an angle of depression, which is the opposite of an elevation angle. When studying heights and distances in trigonometry, it is crucial to understand the angle of elevation and depression. Angles, horizontal lines, and line of sight are the three main terms related to the angle of elevation.

Height of the palm tree is 58 ft

Distance at which I am standing from the tree is 74 ft

As per sum

[tex]tan \theta = \frac{58}{74}[/tex]

[tex]\theta = tan\x^{-1} (\frac{58}{74})[/tex]

[tex]\theta\\[/tex] = [tex]38\x^{o}[/tex]

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Answer:

7 1/2

Step-by-step explanation:

A water tank contains 12 1/2 liters

= 25/2

Two fifth of it was consumedd

= 25/2 ×2/5

= 50/10

= 5

12.5-5

= 7.5

= 7 1/2

1.75% is rate of increse does not change.

What's the math rate?

An unusual ratio in which the two parts are expressed in distinct units is called a rate. The price is 69 for 12 ounces, for instance, if a 12-ounce can of maize costs that much.

                    This is not a proportion of two comparable units, like shirts. This ratio combines the values of the two dissimilar units, cents and ounces.

1960 = 88,000,000

2010 = 242,000,000

formula: (new-old)/old* 100

(242,000,000 - 88,000,000)/88,000,000 * 100

154,000,000/88,000,000*100

1.75*100

= 1.75%

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Let l be the length of the classroom in feet, and w be the width of the classroom in feet. We know that l + 5 = w and l * w = 84.

We can use these two equations to solve for the length and width of the classroom.

First, we can solve the second equation for l:

l = 84 / w

Substituting this expression for l into the first equation gives us:

84 / w + 5 = w

Expanding the left side of the equation gives us:

84 / w + 5 = w

84 / w = w - 5

84 = w^2 - 5w

w^2 - 5w - 84 = 0

This is a quadratic equation that we can solve using the quadratic formula:

w = (5 + sqrt(5^2 - 4 * 1 * -84)) / 2 * 1

= (5 + sqrt(25 + 336)) / 2

= (5 + sqrt(361)) / 2

= (5 + 19) / 2

= 24 / 2

= 12

Now that we know the value of w, we can substitute it back into the equation l = 84 / w to find the value of l:

l = 84 / 12

= 7

Therefore, the dimensions of the classroom are 7 feet by 12 feet.

The coefficient of Y is 10 in  2y 5.

Any integer or symbol that multiplies the variable of a single term or the terms of a polynomial to represent a constant value is known as a coefficient in mathematics. In some phrases, a letter might be substituted for the usual number. For example, x is the variable and a and b are the coefficients in the formula: ax2 + bx + c.

What is a coefficient?

A coefficient is a quantity or number that is coupled with a variable. Frequently, an integer is multiplied by the variable and written next to it. The variables that don't have a corresponding number are presumed to have a coefficient of 1.

10 is the Y coefficient in 2y 5.

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The meaning of adjoining  is nearby or next to.

The terms neighboring, adjoining, contiguous, and juxtaposed denote close closeness. Adjacent may or may not indicate touch, but it always implies the lack of something like in between. A home with a garage attached. Adjoining means meeting and touching at some point or line. Two nearby dwellings are an example of adjacent. People on our block are typically considered our neighbors.

In the English language, “adjacent to” means “next to.” For two angles to be adjacent, they must meet the following three conditions: 1. The two angles must share (or have the same) side. 2. They must share a vertex (i.e. a common starting point for the sides).

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PS is the length of either segment multiplied by two ,PS is 38.

A line connecting the vertex with the middle of the other side forms the median angle. As a result, we may state that PR = QS for the provided.

By equating PR and QS, we can determine X's value.

PR = QS

5x-11 = 2x+7

Combine related terms to get 5x-2x = 7+11; divide both sides by 3 to get the x value; and last, multiply the result by 2 to get x = 6.

Find the value of PR and QS, and we'll demonstrate that two are equal as a result.

Correct: 5(6)-11 = 2(6)+7 19 = 19.

PS is the length of either segment multiplied by two, or simply the product of PR and QS.

PS = 19 x 2 = 19 + 19 = 38 (D) (D)

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Answer: 32

Step-by-step explanation: 4 x 8 = 32 . I am concerned how simple this is ;-;

Answer:

32

Step-by-step explanation:

each boxes have 4 muffins

so,in 8 boxes

by question

8×4=32

The number of seconds, it takes for the balloon to drop below 310 feet is 1.25 seconds

To find out how many seconds it will take for the balloon to drop to below 310 feet, we need to use the information provided and some basic algebra.

Given the starting altitude of the balloon, we know:

h(0) = 1200 feet

The rate of change of the altitude, or the speed at which the altitude is changing, is given as:

dh/dt = −712 feet/second

This tells us that the altitude of the balloon is decreasing at a rate of 712 feet per second. To find out how long it will take for the altitude to drop to 310 feet or less, we can set up the following equation:

h(t) = h(0) + dh/dt * t

We know that h(t) must be less than or equal to 310 feet, so we can substitute this value in for h(t) and solve for t:

310 = 1200 + (−712) * t

This equation can be solved for t by isolating t on one side and then dividing both sides by −712:

t = (1200 - 310) / −712

t = (890) / (−712)

t = 1.25 seconds.

So it will take 1.25 seconds for the balloon to drop below 310 feet.

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Answer:

a trapezoid

Step-by-step explanation:

A trapezoid is a convex quadrilateral. A trapezoid has at least on pair of parallel sides. the parallel sides are called bases while the non parallel sides are called legs

Characteristics of a trapezoid

It has 4 vertices and edges

If both pairs of its opposite sides of a trapezoid are parallel, it becomes a parallelogram

Area of a trapezoid =   x (sum of the lengths of the parallel sides) x height

Perimeter =  sum of lengths of sides of a trapezoid

The amount of money which the chef spends on steak as calculated from the data given is found to be $412.50.

Now as we know that ,

for a meal of 12 meals the chef uses 3 pounds.

Therefore , for a meal of 250 meals the chef uses x pounds

Now , we will solve this proportion.

x=(250 meals*3 pounds)/12 meals

= 62.5 pounds

Now , cost of steaks = 6.60 dollars.

Therefore cost of 62.5 pounds of steaks will be ,

62.5 pound x $ 6.60/pound

=  $ 412.50

A comparison between two numbers is called a proportion. If two sets of provided numbers increase or decrease in the same ratio, then the ratios are said to be directly proportional to each other.

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Answer:

Step-by-step explanation:

(168 mi)/(7 hr) = (24 mi)/hr

(2.5 hr) × (24 mi)/hr = 60 mi

Answer:

I believe she saves $18

Step-by-step explanation:

Because 5 x 9 is 45 and 3 x 9 is 27 45-27 is 18 so i think its $18 but I could be wrong

Answer:

your answer would be y=-3x-15

Step-by-step explanation:

There are 12 weeks will Sonja's balance remain above $377.

What is account balance?

The balance is the sum owed on an account in banking and accounting. The term "balance" in bookkeeping refers to the difference between the total of debit entries and the total of credit entries made into an account over the course of a given financial period. The account shows a debit balance when total debits exceed total credits.

Given:

Sonja has a bank account balance of $1400. Each week, her balance changes by -$85.25. She wants to keep the balance above $377.

We have to find the number of  weeks will Sonja's balance remain above $377.

Let, $1400 - $377 = $1023.

⇒  $1023 / $85.25 = 12

Hence, there are 12 weeks will Sonja's balance remain above $377.

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Answer:

2/1

Step-by-step explanation: