Kevin made 4 identical necklaces each having beads and a pendant. The total cost of the beads and pendants for all 4 necklaces was $23.60. If the beads cost a total of 9.20 how much did each pendant cost

Answers

Answer 1
Answer:
$3.6
Step-by-step explanation:
total cost for all beads and pendant is $23.60
cost for the beads is $9.20
cost for the pendants is 23.60- 9.20 = $14.4
cost for each pendant = 14.4/4 = $3.6

Related Questions

The value of x is 6. What is the value of y ?

Answers

Answer: y = 4.5

scale factor = 4/3

In the electric field [tex]{\vec{E}=3x\hat{i}-2y\hat{j}+5z\hat{k}}[/tex], find the potential difference between the points A(1,3,5) and B(3,2,7)​

Answers

Let's recall that, the potential difference between any two points X(x,y,z) and Y(a,b,c) is given by ;

[tex]{\boxed{\bf{V_{Y}-V_{X}=\displaystyle \bf -\int_{X}^{Y}\overrightarrow{E}\cdot \overrightarrow{dr}}}}[/tex]

So, here ;

[tex]{:\implies \quad \sf \overrightarrow{E}=3x\hat{i}-2y\hat{j}+5z\hat{k}}[/tex]

So, now our second component of the Integrand will just be ;

[tex]{:\implies \quad \sf \overrightarrow{dr}=dx\hat{i}+dy\hat{j}+dz\hat{k}}[/tex]

So, now the whole integrand will just be ;

[tex]{:\implies \quad \sf \overrightarrow{E}\cdot \overrightarrow{dr}=(3x\hat{i}-2y\hat{j}+5z\hat{k})(dx\hat{i}+dy\hat{j}+dz\hat{k})}[/tex]

[tex]{:\implies \quad \sf \overrightarrow{E}\cdot \overrightarrow{dr}=3xdx-2ydy+5zdz}[/tex]

Now, Let's move to the final answer ;

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\int_{X}^{Y}3xdx-2ydy+5zdz}[/tex]

As,X is the point (1,3,5) and Y being (3,2,7) , so seperate the integral into three integrals with limits as follows respectively;

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\bigg(\int_{1}^{3}3xdx-\int_{3}^{2}ydy+\int_{5}^{7}zdz\bigg)}[/tex]

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\bigg(3\int_{1}^{3}xdx-2\int_{3}^{2}ydy+5\int_{5}^{7}zdz\bigg)}[/tex]

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\bigg\{3\bigg(\dfrac{x^2}{2}\bigg)\bigg|_{1}^{3}-2\bigg(\dfrac{y^2}{2}\bigg)\bigg|_{3}^{2}+5\bigg(\dfrac{z^2}{2}\bigg)\bigg|_{5}^{7}\bigg\}}[/tex]

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\bigg\{2\bigg(\dfrac{9}{2}-\dfrac12\bigg)-2\bigg(\dfrac{4}{2}-\dfrac92\bigg)+5\bigg(\dfrac{49}{2}-\dfrac{25}{2}\bigg)\bigg\}}[/tex]

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\{3(4)-(-5)+5(12)\}}[/tex]

[tex]{:\implies \quad \displaystyle \sf V_{Y}-V_{X}=-\{12+5+60\}}[/tex]

[tex]{:\implies \quad \displaystyle \boxed{\bf{V_{Y}-V_{X}=-77\:\: Volt}}}[/tex]

Hence, this is the required answer

True or False: In an exponential regression, the data points tend to increase in one direction and flatten out in the other direction.

Answers

Answer:

T

Step-by-step explanation:

The regression line is flat when there is no ability to predict whatsoever. The regression line is sloped at an angle when there is a relationship. The extent to which the regression line is sloped, however, represents the degree to which we are able to predict the y scores with the x scores

What is the solution to the system of equation s x+y=4. X=y-1

Answers

Answer:

x = 3/2

y = 5/2

Step-by-step explanation:

x + y = 4

x = y - 1


substitute y - 1 in for x in the first equation, to find y


y - 1 + y = 4

2y - 1 = 4


add 1 on both sides

2y - 1 = 4

+1 +1

2y = 5


divide by 2 on both sides

2y/2 = 5/2

y = 5/2


subtitute y in for the second equation, to find x

x = 5/2 - 1

x = 5/2 - 2/2

x = 3/2


so x = 3/2 and y = 5/2

to double check, plug x and y in the first equation

3/2 + 5/2 = 4

8/2 = 4

4 = 4

The area of South America is approximately 1.78 × 107 square kilometers. Its population is approximately 3.50 × 108 people. What is the approximate population density (people per square kilometer) of South America? Write your answer in standard form. If necessary, round your answer to the nearest hundredth.
A: 19.66 people/km^2

B: 1.97 × 10^15 people/km2

C: 5.09 people/km^2

D: 1.97 × 10^1 people/km^2

Answers

Answer: 19.66 people/km^2, A

Step-by-step explanation:

The population density will be equal to 82.96 people/km2.

The correct option is B.

What is an expression?

Expression in maths is defined as the collection of numbers variables and functions by using signs like addition, subtraction, multiplication, and division.

Numbers (constants), variables, operations, functions, brackets, punctuation, and grouping can all be represented by mathematical symbols, which can also be used to indicate the logical syntax's order of operations and other features.

here, we have,

Given that the area is 1.78 × 10⁷ km² with 3.50 × 10^8 people.

The population density will be calculated as below:-

Density = people / km² = ( 3.50 × 10^8 ) / ( 1.78 x 10⁷ )

Density =19.66

Density = 19.66 people/km²

Therefore, the population density will be equal to 82.96 people/km2. The correct option is A.

To know more about an expression follow:

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Use the definition of the derivative as a limit to find the
derivative f′ where f(x)= √ x+2.

Answers

Step-by-step explanation:

If the equation is

[tex] \sqrt{x + 2} [/tex]

Then, here is the answer.

The definition of a derivative is

[tex] \frac{f(x + h) - f(x)}{h} [/tex]

Also note that we want h to be a small, negligible value so we let h be a value that is infinitesimal small.

So we get

[tex] \frac{ \sqrt{x + h + 2} - \sqrt{x + 2} }{h} [/tex]

Multiply both equations by the conjugate.

[tex] \frac{ \sqrt{x + h + 2} - \sqrt{x + 2} }{h} \times \frac{ \sqrt{x + h + 2} + \sqrt{x + 2} }{ \sqrt{x + h + 2} + \sqrt{x + 2} } = \frac{x + h + 2 - (x + 2)}{h \sqrt{x + h + 2} + \sqrt{x + 2} } [/tex]

[tex] \frac{h}{h \sqrt{x + h + 2} + \sqrt{x + 2} } [/tex]

[tex] \frac{1}{ \sqrt{x + h + 2} + \sqrt{x + 2} } [/tex]

Since h is very small, get rid of h.

[tex] \frac{1}{ \sqrt{x + 2} + \sqrt{x + 2} } [/tex]

[tex] \frac{1}{2 \sqrt{x + 2} } [/tex]

So the derivative of

[tex] \frac{d}{dx} ( \sqrt{x + 2} ) = \frac{1}{2 \sqrt{x + 2} } [/tex]

Part 2: If your function is

[tex] \sqrt{x} + 2[/tex]

Then we get

[tex] \frac{ \sqrt{x + h} + 2 - ( \sqrt{x} + 2) }{h} [/tex]

[tex] \frac{ \sqrt{x + h} - \sqrt{x} }{h} [/tex]

[tex] \frac{x + h - x}{h( \sqrt{x + h} + \sqrt{x}) } [/tex]

[tex] \frac{h}{h( \sqrt{x + h} + \sqrt{x} ) } [/tex]

[tex] \frac{1}{ \sqrt{x + h} + \sqrt{x} } [/tex]

[tex] \frac{1}{2 \sqrt{x} } [/tex]

So

[tex] \frac{d}{dx} ( \sqrt{x} + 2) = \frac{1}{2 \sqrt{x} } [/tex]

Help! 10 Points !!
A line passes through the point (-8. 5) and has a slope of -5/4

Answers

Slope point form for the equation of a straight line

=m(x-x1) + y1

y= 5/4 (x-8) +5

y= 5/4x - 10 + 5

y= 5/4x - 5

A bag contains 2 red marbles, 7 blue marbles and 5 green marbles. If two marbles are
drawn out of the bag, what is the exact probability that both marbles drawn will be
blue?

Answers

Answer:

1/2

Step-by-step explanation:

There are :-

⇒ 2 red marbles

⇒ 7 blue marbles

⇒ 5 green marbles

Probability (Blue)

= No. of blue marbles / No. of total marbles= 7 / (2 + 7 + 5)= 7/14= 1/2

Help picture below problem 16

Answers

Concept :-

We have studied the law which states that the sum of all angles in a triangle is 180°, this is known as angle sum property of a triangle. We can solve this question based on that property.

Solution :-

Let us assume the missing angle to be x,

Therefore,

→ 66° + 71° + x = 180° ( Angle sum property of a triangle )

→ 137° + x = 180°

→ x = 180° - 137°

→ x = 43°

Thus, the measure of the missing angle is 43°.

Hope that helps :)

f(x) = x^2-3
What is the average rate of change on the interval [-5, 2] ?

Answers

Answer:

[tex](-3)[/tex].

Step-by-step explanation:

Over this interval, the change in the value of this function is:

[tex]f(-5) - f(2) = 22 - 1 = 21[/tex].

The corresponding change in the value of [tex]x[/tex]:

[tex](-5) - 2 = -7[/tex].

The average rate of change of function [tex]f[/tex] over this interval is equal to the change in the function value divided by the corresponding change in [tex]x[/tex]:

[tex]\begin{aligned}& (\text{average rate of change}) \\ =\; & \frac{(\text{change in function value})}{(\text{change in $x$})} \\ =\; & \frac{f(-5) - f(2)}{(-5) - 2} \\ =\; & \frac{22 - 1}{-7} \\ =\; & \frac{21}{-7} \\ =\; & -3\end{aligned}[/tex].

Thus, the average rate of change of [tex]f(x) = x^{2} - 3[/tex] over the interval [tex][-5,\, 2][/tex] would be [tex](-3)[/tex].

what is the formula for the volume of a sphere with radius r = 5?

Answers

Answer:

  V = (4/3)π·5³ = 500π/3

Step-by-step explanation:

The formula for the volume of any sphere as a function of its radius is ...

  V = (4/3)π·r³

When the sphere has a radius of 5, we replace r in the formula with 5. The formula for the volume of a sphere with radius 5 is ...

  V = (4/3)π·5³

__

When that is evaluated, the volume is found to be ...

  V = 500π/3 ≈ 523.599 . . . cubic units

A large set of data was collected and analyzed for the majors of college seniors in the U.S. From the scatter plots produced the following associations were observed. The linear model P(t) 2,376 + 73,219 can be used to estimate the number of college seniors who graduated with a bachelor's degree in psychology, tyears after 2000 - The linear model B(t) = 2, 414t + 56, 545 can be used to estimate the number of college ( seniors who graduated with a bachelor's degree in biology, tyears after 2000. Which of the following statements are true? The number of psychology degrees increases by about 73,219 each year after 2000. The number of biology degrees increases by about 2.414 each year after 2000. About 73.000 students graduated with degrees in psychology in 2000. About 2.400 students graduated with degrees in biology in 2000. in 2000, more students graduated with psychology degrees than biology degrees​

Answers

Using linear function concepts, it is found that the true statements are as follows:

The number of biology degrees increases by about 2.414 each year after 2000. About 73.000 students graduated with degrees in psychology in 2000.In 2000, more students graduated with psychology degrees than biology degrees​.

What is a linear function?

A linear function is modeled by:

[tex]y = mx + b[/tex]

In which:

m is the slope, which is the rate of change, that is, by how much y changes when x changes by 1.b is the y-intercept, which is the value of y when x = 0, and can also be interpreted as the initial value.

In this problem, for psychology, the model for the number of graduated students in t years after 2000 is:

P(t) = 2,376t + 73,219.

For biology, it is given by:

B(t) = 2,414t + 56, 545

Hence, the correct statements are:

The number of biology degrees increases by about 2.414 each year after 2000. About 73.000 students graduated with degrees in psychology in 2000.In 2000, more students graduated with psychology degrees than biology degrees​.

More can be learned about linear function concepts at https://brainly.com/question/24808124

The population of a city increased from 21,400 to 27,700 between 2007 and 2016. Find the change
of population per year if we assume the change was constant from 2007 and 2016.

Answers

Answer:

700

Step-by-step explanation:

2016 - 2007 = 9

27,700 - 21,400 = 6300

6300 / 9 = 700.

A researcher is interested in determining whether teens who transfer schools after their freshman year in high school demonstrate
more behavior problems on the Achenbach Youth Self Report test with a population mean of 50 and a population standard deviation of
10. The researcher has a sample of 100 teens with a mean score of 59. What is your obtained z?

Answers

The z-score of the number of teens that transfered schools is the standard score

The obtained value of z is 5

How to determine the value of z?

The given parameters are:

Population mean, μ = 50Population standard deviation, σ = 10Sample, x = 100Sample mean = 59

The z-value is calculated using:

z = (x - μ)/σ

Substitute known values in the above formula

z = (100 - 50)/10

Evaluate the difference

z = 50/10

Evaluate the quotient

z = 5

Hence, the obtained value of z is 5

Read more about z-scores at:

https://brainly.com/question/25638875


Someone pls

.
A
A
A
A
A
A
S

Answers

Answer:

7

Step-by-step explanation:

Degree of a polynomial is a variable's highest exponent

In this expression the degree is 7

Answer:

7

Step-by-step explanation:

If you used

P.E.M.D.A.S

Brainly please I worked so hard for this answer

PLEASE HELP PLEASE HELP

Answers

36 cuz formula for area is length times the width. 4 x 9 = 36

Can you be serious and more understanding about the home work

Answers

Answer:

yes

Step-by-step explanation:

is there a specific question?

Answer: All children should be doing homework. But the amount and quality should change." His basic prescription.

Step-by-step explanation:

2 points
Daria earns h dollars per hour at the grocery store. She works 9 hours per week. She writes the expression 9 • h • 4 to represent how much
money she earns in a four-week month. Daria's boss writes the expression 36h. Which person's expression tells you how many hours Daria
works per four-week month? EXPLAIN YOUR REASONING.

Answers

Answer:

Daria's boss expression

Step-by-step explanation:

Her boss expression because it's asking about the hours worked per four week month. Daria's expression represents the 9 hours she works per week for the 4 weeks in the month.

Her boss expression represents the total number of hours she works altogether in all the four weeks in the month.

write THREE equivalent fractions for the following fractions:

25/50 = ___ = ___ =____​

Answers

Answer:

25/50 = 5/10 = 1/2

Step-by-step explanation:

I hope it will be helpful

Answer:

25/50 = 5/10 = 1/2

Hooe this helps you :)

the figure represent 7/9 0f a full circle Find the measure of the marked central angle

Answers

Step-by-step explanation:

tbh I don't know I need help with that too please like this comment

The measure of the marked central angle of the sector will be 280°.

What is the arc length of the sector?

Let r is the radius of the sector and θ be the angle subtended by the sector at the center. Then the arc length of the sector of the circle will be

Arc = (θ/2π) 2πr

The figure addresses 7/9 of a complete circle. Then the arc length of the circle will be given as,

Arc / P = 7/9

Simplify the equation, then we have

(θ/2π) 2πr / 2πr = 7/9

θ/2π = 7/9

θ = 14π / 9

θ = 280°

The central angle of the sector will be 280°.

More about the arc length of the sector link is given below.

https://brainly.com/question/15955580

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When do you say that a given quadrilateral is a parallelogram?

Answers

Answer:

Theorem : If in a quadrilateral, each pair of opposite angles is equal, then it is a parallelogram. Given : ABCD is a quadrilateral in which ∠A = ∠C and ∠B = ∠D. We know that the sum of the angles of a quadrilateral is 360o.

Step-by-step explanation:

hope that helps

-3/5m + 8 = 20
what is the answer of m

Answers

[tex]\qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]

Let's solve ~

[tex]\qquad \sf  \dashrightarrow \: - \frac{ 3}{5} m + 8 = 20[/tex]

[tex]\qquad \sf  \dashrightarrow \: - \frac{ 3}{5} m = 20 - 8[/tex]

[tex]\qquad \sf  \dashrightarrow \: - \frac{ 3}{5} m =12[/tex]

[tex]\qquad \sf  \dashrightarrow \: - \frac{ }{} m =12 \times \frac{5}{3} [/tex]

[tex]\qquad \sf  \dashrightarrow \: - m = 4 \times 5[/tex]

[tex]\qquad \sf  \dashrightarrow \:m = - 20[/tex]

➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖

Consider the graph of the quadratic function. Which
interval on the x-axis has a negative rate of change?
-2 to -1
-1.5 to 0
0 to 1
1 to 2.5

Answers

The only interval with a negative rate of change is the last one:

[1, 2.5]

When the rate of change is negative?

For an interval (a, b) and a function f(x), the rate of change is defined as:

[tex]r = \frac{f(b) - f(a)}{b - a}[/tex]

So the rate of change is only negative when the function evaluated on the first value of the interval is larger than the function evaluated in the second one.

For example, on the interval [1, 2.5} we can see that:

f(1) = 3

f(2.5) = -1

Then on this interval, the rate of change will be negative, meaning that this is the correct option.

If you want to learn more about rates of change, you can read:

https://brainly.com/question/8728504

Answer:

It's D: 1 to 2.5

Step-by-step explanation:

It's D: 1 to 2.5

Find the equation of a line that passes through the point (0,-4) and has a gradient of 2. Leave your answer in the form y=mx+c​

Answers

Answer:

y=2x-4

Step-by-step explanation:

y-y1=m(x-x1)

y-(-4)=2(x-0)

y+4=2x-0

y=2x-0-4

y=2x-4

PLEASE HELP!!!!

Earth is about 1.5 x 10^8 kilometers away from the sun. Saturn is about 1.4 x 10^9 kilometers away from the sun. How many times closer to the sun is Earth than Saturn? Give answer is standard form and round to the nearest tenth.

If you can, please explain, or just show what you did

Answers

Answer:

8.33

Step-by-step explanation:

Answer: 8.33 minutes will it take to travel from the sun to the earth. Step-by-step explanation: Distance of the Earth from the Sun = d = 1 km = 1000 m.

Answer: 9.33

Step-by-step explanation: you divide Saturn by earth

Change 75m to decimeters

Answers

Answer:

750 decimeters

Step-by-step explanation:

1 meter is equal to 10 decimeters.

so 75 times 10 equals your answer: 750 decimeters

Hope that helps!

Find angles B, E, C, and D, given that angle m A=140° and m F=130°.
*Picture is not drawn to scale*

Answers

Answer:

Angle B=40 degrees

Angle C= 90 degrees

Angle E=50 degrees

Please Mark Brainliest

these answer- I am sure they ar correct

Four friends are order pizza from a take away.
The amount of pizza each person eats is shown as a fraction below
Matthew eats 0.8of a pizza
Lily eats 3/4of a pizza
George eats 77%opizzas f a pizza
Sam eats 82%of a pizza
Which person eats the most pizza?
You must show your workings ​

Answers

Answer:

Sam ate the most pizza.

Step-by-step explanation:

Mathew: 0.8 is equal to 80%

To get a percentage, you need to move the decimal two places to the right.

Lily: 3/4 = 75%

George: 77%

Sam: 82%

help me please. either one is fine.

Answers

7)
95+(3x+23)+(7x-4)+(9x-6)+90 = (5-2) x 180
x = 18

9)
41+(3x+6)+(7x-11)+62+(4x+7)+(6x-5) = 360
x = 13


A bedroom door in the house has the same dimension as the front door but the length is 30 inches rather than 36 inches how much greater is the volume of the front door than than the bedroom door

Answers

Answer:

6/5

Step-by-step explanation:

Calculate the volume by multiplying the measured length and width of the space together, then multiply the result by the height of the room. From the example, 10 * 25 feet = 250 square feet, and 5 * 10 feet = 50 square feet.

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