Henry purchased a prepaid phone card $40.50 for . Calls cost 10 cents a minute using this card. The credit, C (in dollars), left on the card after it is used for 15 minutes of calls is given by the following. How much credit is left on the card after Henry uses it for minutes of calls?

Answers

Answer 1

By solving the given equation we know that $32.7 credit is left on the phone.

What are equations?

The definition of an equation in algebra is a logical statement that proves two formulas are equal.

Take the equation 3x + 5 = 14, wherein 3x + 5 and 14 are two expressions that are separated by the symbol "equal."

So, we have the equation:

C(x)-35.50-0.07x

As Henry use it for 40 minutes:

Now, calculate the amount left as follows:

C(x) = 35.50 - (0.07 x 40)

C(x) = 35.50 - 2.8

C(x) = $32.7 left

Therefore, by solving the given equation we know that $32.7 credit is left on the phone.

Know more about equations here:

https://brainly.com/question/28937794

#SPJ1

Complete question:

Henry purchased a prepaid phone card for $35.50. Calls cost 7 cents a minute using this card. The credit, C(in dollars), left on the card after it is used for x minutes of calls is given by the following function. C(x)-35.50-0.07x . How much credit is left on the card after Felipe uses it for 40 minutes of calls?


Related Questions

Which equations are set up correctly to solve for the unknown side length?

Answers

The equations that can be set up correctly to find the length of the unknown side using the Pythagorean theorem are:

6² + x² = 17²

x² + 6² = 17²

What is the Pythagorean Theorem?

The Pythagorean Theorem is a statement in mathematics that states that in a right triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides.

The theorem can be written as an equation:

c² = a² + b², where c is the length of the hypotenuse, and a and b are the lengths of the other two sides.

Using the Pythagorean theorem, the equations that can be set up correctly to find the value of x are:

6² + x² = 17²

x² + 6² = 17²

Learn more about the Pythagorean theorem on:

https://brainly.com/question/343682

#SPJ1

the question is.


urine completed the square to solve the equation 0 = 3x to the square root of 2 - 9x + 27

Answers

Yes, Urie correctly completed the square to solve the equation 0 = 3x + 9 to the square root of 2 - 9x + 27.

How to solve square root equation? A square root equation is an equation that contains a square root of a variable, typically represented by the radical symbol √. To solve a square root equation, you must isolate the radical symbol on one side of the equation and then square both sides of the equation.For example, if the equation is √x + 3 = 7, you would need to subtract 3 from both sides to isolate the radical symbol on the left side of the equation. This would give you √x = 4. Then, square both sides of the equation to get rid of the radical symbol. This would give you x = 16, which is the solution to the equation.In general, to solve a square root equation, you must first isolate the radical symbol on one side of the equation. Then, square both sides of the equation to get rid of the radical symbol, which will give you the solution to the equation. It is important to remember to always square both sides of the equation, so that the equation is still balanced after the radical symbol is removed.

To learn more about square root of equation refer to:

https://brainly.com/question/28428939

#SPJ1

What is the formula of property?

Answers

The formula of commutative property is α + β = β + α or α × β = β × α.

The commutative property is the property that deals with the arithmetic operations of addition and multiplication. So mathematically, if we change the order of the operand and it does not change the result of the arithmetic operation then that particular arithmetic operation is commutative.

If two numbers α and β are given, then the formula of the commutative property of numbers is given as,

α + β = β + α

α × β = β × α

α - β ≠ β - α

α ÷ β ≠ β ÷ α

To know more about commutative property, here

https://brainly.com/question/778086

#SPJ4

27 5/3 in simplest radical form

Answers

The value of 27 5/3 in simplest radical form will be 86 / 3.

How to illustrate the exponent?

The fraction simply means a piece of a whole. In this situation, the number is represented as a quotient such that the numerator and denominator are split. In this situation, in a simple fraction, the numerator as well as the denominator are both integers.

Here the value of 27 5/3 in simplest radical form will be the calculated thus:

(27 × 3) + 5 / 3

= (81 + 5) / 3

= 86 / 3

The value in radical form will be 86 / 3.

Learn more about Fraction on:

https://brainly.com/question/78672

#SPJ1

Identify the center of dilation.
-8
8
0
-4
ty
-8
8

Answers

Answer:The slope of the given line is -4

Step-by-step explanation:

Counting More Pebbles Along the Path page 1 of 2: Look at the pebbles along each part of the path. Fill in the missing numbers. 15 13 16 72 CHALLENGE Hansel and Gretel used a pebble to mark every 10 steps as they walked along the path. How many steps have they taken when they get to the last pebble on this part of the path? ____________Use numbers or words to explair how you know

Answers

The missing numbers are 14 and 17. there are 50 steps taken to reach the last pebble on this part of the path.

What is the missing number?

Missing numbers are the numbers that have been missed in the given series of a number with similar differences among them.

let's take a look at pebbles along each part of the path, there is 1 number of addition to each pebble number to go on next pebble.

i.e. 12, 13, 14, 15, 16, 17

so, the missing numbers are 14 and 17.

now, as given Hansel and Gretel used a pebble to mark every 10 steps as they walked along the path. How many steps have they taken when they get to the last pebble on this part of the path?

so, to go on next pebble there are 10 steps to walk.

therefore, from starting pebble  number 12 to last pebble number 17, there are 50 steps ( difference between two pebbles is 10 steps).

hence, the missing numbers are 14 and 17. there are 50 steps taken to reach the last pebble on this part of the path.

To learn more about missing numbers visit : brainly.com/question/12750881

#SPJ4

What is the solution to -6x - 7 = 35?

Answers

Answer:

Step-by-step explanation:

if it is 35 because if you put together two negative numbers they become positive

I hope it helps you :)

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

Lets get it done ~

[tex]\qquad \sf  \dashrightarrow \: 6x - 7 = 35[/tex]

[tex]\qquad \sf  \dashrightarrow \: 6x - 7 + 7 = 35 + 7[/tex]

[tex]\qquad \sf  \dashrightarrow \: 6x = 35 + 7[/tex]

[tex]\qquad \sf  \dashrightarrow \: 6x = 42[/tex]

[tex]\qquad \sf  \dashrightarrow \: x = 7[/tex]

How do you find an area example?

Answers

Answer:

To find the area of a rectangle, multiply its height by its width. For a square you only need to find the length of one of the sides (as each side is the same length) and then multiply this by itself to find the area......

Step-by-step explanation:

- 1 2/7x-1=26
Show work

Answers

The expression  [tex]$1\frac{2}{7}x -1=26[/tex]  gives {x} value as equivalent to 21.

What is expression?

In mathematics, an expression or mathematical expression is a finite combination of symbols that is well-formed according to rules that depend on the context.

Mathematical symbols can designate numbers (constants), variables, operations, functions, brackets, punctuation, and grouping to help determine order of operations and other aspects of logical syntax.

Given is the expression as -

[tex]$1\frac{2}{7}x -1=26[/tex]

We can write the expression as -

(9/7)x - 1 = 26

(9/7)x = 27

x = (27 x 7)/9

x = 3 x 7

x = 21

Therefore, the expression  [tex]$1\frac{2}{7}x -1=26[/tex]  gives {x} value as equivalent to 21.

To solve more questions on expressions, visit the link below -

brainly.com/question/1041084

#SPJ1

5 students are going on a field trip and 5 students are staying at school. What is the ratio of the number of students who are staying at school to the total number of students?

Answers

the answer is 5:10,

At charles school, 15 of the 75 students in seventh grade play in the jazz band. How many seventh graders play in the jazz band?.

Answers

The jazz band has 15 seventh graders playing according to the ratio.

What is the ratio?

A ratio, which is a number, is a way to represent one quantity as a portion of another. A ratio can only be compared when the two numbers in it have the same unit. To compare two objects, ratios are utilized.

Given One fifth of the 75 seventh graders at Charles School participate in the jazz band.

Presented as a ratio

75 pupils, or 1/5 of them, participate in the jazz band.

75 pupils out of the total play in the jazz band.

15 kids in total participate in the jazz band.

15 seventh graders are therefore playing in the jazz band in accordance with the ratio.

Hence, The jazz band has 15 seventh graders playing according to the ratio.

Learn more about ratios here:

brainly.com/question/13419413

#SPJ4

Using the constant of proportionality, write an equation for this proportional relationship:

You can buy 14 apples for 28 euros.

Use a to represent number of apples and c to represent the cost in euros. Please write your equation starting with c=

Answers

c = 14a/28

This equation represents the proportional relationship between the number of apples (a) and the cost in euros (c). The constant of proportionality is 14/28, which means that for every 14 apples, the cost is 28 euros. By dividing both sides by 14, we can also write the equation as a = c/2. This means that for every 2 euros, you can buy one apple.

Learn more about "constant of proportionality": https://brainly.com/question/29126727

At Aaron's Automobile's, Bob made $150,000 total in sales and commission last week. If commission is 20%, how much were Bob's sales?

Last week's sales were $______

Answers

Answer: 30,000

Step-by-step explanation:

150,000 x 0.2 = 30,000

What are the zeros of quadratic function 2x² 7x 3?

Answers

The zeros of quadratic function 2x² - 7x + 3 = 0 are 3 and 1/2.

There are several methods for solving a quadratic equation of the form ax² + bx + c = 0. In our case, use the quadratic formula x = (-b ± √(b² - 4ac)) / 2a to find the zeros or the solutions for x.

Plug in the values to the formula and solve for x.

x = (-b ± √(b² - 4ac)) / 2a

x = (--7 ± √(-7² - 4(2)(3))) / 2(2)

x = (7 ± √49 - 24) / 4

x = (7 ± √25) / 4

x = (7 ± 5) / 4

x = 3   ;   x = 1/2

Hence, the zeros of quadratic function 2x² - 7x + 3 = 0 are 3 and 1/2.

Learn more about quadratic formula here: https://brainly.com/question/1214333

#SPJ4

G(1) = 50
G(n) = 8 - g (n-1)
G(2) =

Answers

The value of G(2) of the given sequence formula is; -42

How to solve Arithmetic sequence?

The general formula for the nth term of an arithmetic sequence is;

aₙ = a + (n - 1)d

where;

a is first term

n is position of term

d is common difference

We have the following parameters;

G(1) = 50

G(n) = 8 - g (n-1)

Thus;

G(2) = 8 - g(2-1)

G(2) = 8 - g(1)

Since (g(1) = 50 ), then we have;

G(2)= 8 - 50

G(2) = -42

Read more about Arithmetic Sequence at; https://brainly.com/question/6561461

#SPJ1

The perimeter of a rectangle is 172 feet. Find the length and width if the length is an integer and the width is 2 times the next consecutive integer.

Answers

The length and width of the rectangle is 28 feet and 58 feet respectively.

How to find the sides of a rectangle?

A rectangle is a quadrilateral with opposite sides equal to each other and opposite sides parallel to each other.

Therefore, the perimeter of a rectangle is the sum of the whole 4 sides of the rectangle.

Hence, the perimeter of a rectangle is 172 feet.

perimeter of a rectangle = 2(l + w)

where

l = lengthw = width

l = x

w = 2(x + 1) = 2x + 2

Therefore,

172 = 2(x + 2x + 2)

172 = 2(3x + 2)

divide both sides by 2

172 / 2 = 3x + 2

86 = 3x + 2

86 - 2 = 3x

3x = 84

divide both sides by 3

x = 84 / 3

x = 28

Therefore,

length = 28 feet

width = 2(28) + 2 = 58 feet

learn more on rectangle here: https://brainly.com/question/14656866

#SPJ1

Which expression is equivalent to -8.2 - 5?
Choose 1 answer:
A
B
5- (-8.2)
-8.2 + 5
8.25
-8.2+(-5)

Answers

The expression equivalent to - 8.2 - 5 is - 8.2 + (-5)

What is an expression?

A mathematical expression is a phrase that includes at least two numbers or variables, and at least one arithmetic operation. The mathematical operations used can be addition, subtraction, multiplication or division.

Note ,

         - × - = +

         - × + = -

         + × + = +

For the expression - 8.2 - 5

In the above expression, we are subtracting positive integer 5 from -8.2

  So we get the answer as

                 -8.2-5 = = -13.2

Now this is the solution we should get while solving the given options.

  a) 5 - ( -8.2)  = 5 + 8.2 = 13.2

  b) -8.2 + 5 = - 3.2

  c) -8.2 -5 [tex]\neq[/tex] 8.25 (as seen above)

   d) - 8.2 + ( -5) = -8.2 - 5 = -13.2

Comparing the solutions, we get that option(d) matches with the required answer.

Therefore option(d) is the correct expression that gives the same answer.

To learn more about expression, follow the link.

https://brainly.com/question/723406

#SPJ1

     

     

Is any set of ordered pair?

Answers

Any set of ordered pair cannot be called as a function , the ordered pairs that in which no two different ordered pairs have the same x coordinate is called as a Function .

What is a Function ?

The set of ordered pair (x,y) is called a function, in which no two different ordered pairs have the same x coordinate. and the equation that produces such a set of ordered pairs can be called as function.

For Example : Let us Consider ordered pairs , F = [tex][(1,5) , (3,6)][/tex] ;

we see that ,  the element 1 has the image as 5 , and the element 3 has the image as 6 .

So , we can conclude  that , the each value of x has exactly only one corresponding value of y .

Therefore , the ordered pair can be called as a function .

The given question  is incomplete , the complete question  is

Is any set of ordered pair is called a Function ?

Learn more abut Ordered Function  here

https://brainly.com/question/28931422

#SPJ4

What are the 3 steps of factoring?

Answers

The three steps of factoring include taking the common component out of the polynomial then simplifying the polynomial such that the most simple values are left and finally rearrangement.

If we are provided with the polynomial that is very complex in nature then first thing we have to do in order to solve the problem related to that polynomial is to factorise the polynomial.

The factory of that particular polynomial can be done by taking out the most common component out of the polynomial in a multiplication.

After this we have to simplify the polynomial such that only the simplest values are left in the polynomial and finally we have to rearrange the polynomial because after such operations on that polynomial the polynomial will not be easy to understand in the first look of it.

To know more about factors, visit,

https://brainly.com/question/18187355

#SPJ4

What is the coefficient of XYZ?

Answers

Therefore , the solution of the given problem of expression comes out to be the coefficient of given expression  XYZ  is 1.

What exactly does expression mean?

By substituting each variable with a number and conducting mathematical functions, an algebraic formula must be checked. The solution variable in the previous example is identical to 6 since 79 + 8 = 87. To evaluate the expression, we can replace the variables values with ones we are familiar with.

Here,

Given :

XYZ

To find the coefficient of given expression ,

Thus,

From observing we can see XYZ

can be written as

=>1*XYZ

Where 1 is coefficient.

Therefore , the solution of the given problem of expression comes out to be the coefficient of given expression  XYZ  is 1.

To know more about expressions visit :-

brainly.com/question/14083225

#SPJ4

I need you to solve this

Answers

Answer:

Step-by-step explanation:

When dividing like bases (x is our base) we simplify by subtracting the exponents, top minus bottom. Since the exponents are fractions, we need a common denominator.

[tex]\frac{1}{5} -\frac{2}{15}=\frac{3}{15} -\frac{2}{15}=\frac{1}{15}[/tex]

thus, the simplification is [tex]x^\frac{1}{15}[/tex]

Answer:

(x 1/5)/(x 2/15)=.

(x1/5)× 15/2x

=15x/10x

=1.5

What is the slope of the line described by the equation below

Answers

Answer: -3

Step-by-step explanation: Y=MX+B

Answer:

−3

Step-by-step explanation:

y-5=-3(x-17)

y=-3x+51+5

y=-3x+56

if we have this function:

y=mx+b

The slope is "m".

In this case, m=-3

Answer: sope -3

One of the legs of a right triangle measures 7 cm and the other leg measures 17 cm. Find the measure of the hypotenuse. If necessary round to the nearest tenth.

Answers

Answer:

[tex]\huge\boxed{\sf H=18.4\ cm}[/tex]

Step-by-step explanation:

Given that,

Base = 7 cm

Perpendicular = 17 cm

Hypotenuse = H

Using Pythagoras theorem.

[tex](Hypotenuse)^2=(Base)^2+(Perpendicular)^2\\\\(H)^2=(7)^2+(17)^2\\\\(H)^2=49+289\\\\(H)^2=338\\\\Take \ square\ root \ on \ both\ sides\\\\\sqrt{(H)^2} =\sqrt{338} \\\\H=18.4\ cm\\\\\rule[225]{225}{2}[/tex]

How do you know when to change base?

Answers

When you are doing calculations, you can usually tell when you need to change base by looking at the problem. If the problem includes fractions, a base other than 10 may be more efficient. If the problem includes exponents, a base other than 10 may be necessary.

Changing Base for Complex Calculations

When working with numbers, it is important to know what base the numbers are in in order to correctly perform calculations. The base of a number is the number of digits used to express it, meaning that the base of a number can range from base 2 (binary) to base 36 (base 36 uses the numbers 0-9 and the letters A-Z).

Changing the base of a number can be helpful when dealing with fractions, exponents, and other complex calculations. To change the base of a number, divide the number by the base and then divide the remainder by the base, continuing to divide until the remainder equals 0.

Learn more about complex calculations: https://brainly.com/question/14344386

#SPJ4

What type of dilation is formed when the scale factor K is greater than 1 blank options?

Answers

An expansion where image size increased is formed when scale factor k is greater than 1

What is Dilation ?

The process of dilation entails scaling or changing a thing. It is a transformation that uses the specified scale factor to make the objects smaller or larger.

The initial figure is referred to as the pre-image, and the new figure that results from dilatation is known as the image.

The resizing happens from a point called the center of dilation. It is the center of dilation from which the objects/figures are expanded or contracted. Scale factor is a number by which the size of any geometrical figure can be changed with respect to its original size.

when the scale factor K is greater than 1 , The image will enlarged

Hence, An expansion will be occur.

To know more about Dilation here

brainly.com/question/13176891

#SPJ4

Note: Enter your answer and show all the steps that you use to solve this problem in the space provided.


Write an equation with a variable on both sides of the equal sign that has infinitely many solutions. Solve the equation and explain why it has an infinite number of solutions.

PLEASE HURRY IM TAKING EXAM pre algebra

Answers

The equation which gives infinite solutions, x-10+x = 8+2x-18.

What is Equation?

Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.

It demonstrates the equality of the relationship between the expressions printed on the left and right sides. LHS = RHS is a common mathematical formula.

Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.

Given:

For the infinite solution the both side of equation must contain equal quantity.

For example,

x-10+x = 8+2x-18

now, solving for x

x-10+x = 8+2x-18

2x-10 = 2x-10

-2x = -2x

-10 = -10

As, both sides are equal  which shows the system of equation.

Learn more about Equation here:

https://brainly.com/question/29657983

#SPJ1

Need Answer desperately pls help

Answers

Answer:

7) B.

8) D.

Step-by-step explanation:

The points (3, 9) and (–3, –9) are plotted on the coordinate plane using the equation y = a • x.
What is the value of a?

Answers

The value of {a} is equivalent to 3.

What is the general equation of a straight line?

The general equation of a straight line is -

y = mx + c

{m} - slope.

{c} - intercept along the y - axis.

Given is the equation of a straight line → y = ax

The points (3, 9) and (–3, –9) are plotted on the coordinate plane using the equation y = ax, this means that -

9 = a x 3

a = 3

and

- 9 = a x - 3

a = 3

Therefore, the value of {a} is equivalent to 3.

To solve more questions on straight lines, visit the link below -

brainly.com/question/28951560

#SPJ1

How do I know if my cervix is dilating?

Answers

Knowing if your cervix is dilating typically involves a physical examination by a healthcare provider.

During labor, a healthcare provider will check the dilation of your cervix by performing a pelvic exam. They will use their fingers to feel the cervix, which is located at the top of the vagina, and determine the degree of dilation.

Cervical dilation is measured in centimeters, and full dilation is considered to be 10 centimeters. Before labor begins, the cervix is typically closed and has a firm consistency. As labor progresses, the cervix will start to soften and thin out, and will eventually open, or dilate.

Some women might experience Braxton Hicks contractions, which are sometimes referred as "false contractions" as they can be mistaken for the start of labor, but Braxton Hicks contractions do not cause cervical dilation.

It's important to note that dilation is just one of the factors that indicate that labor is imminent. It is not the only factor and some women can have a fully dilated cervix for days before going into active labor.

In conclusion, knowing if your cervix is dilating typically involves a physical examination by a healthcare provider, who will perform a pelvic exam to feel the cervix and determine the degree of dilation.

Cervical dilation is measured in centimeters, with full dilation being 10 centimeters. Be aware that dilation is just one of the factors that indicate labor is imminent.

Learn more about dilation at

https://brainly.com/question/28147754

#SPJ4

How do you find a quadratic function with a vertex and a point?

Answers

The  quadratic function has the formula f(x) = ax2 + bx + c, with a, b, and c being integers and a not equal to zero.

What is quadratic function?A quadratic function has the formula f(x) = ax2 + bx + c, with a, b, and c being integers and a not equal to zero. A parabola is a curve that represents the graph of a quadratic function. Parabolas can have openings that are upward or downward, different "widths" or "steepnesses," but they all share the same fundamental "U" shape. In mathematics, a quadratic issue is any problem that involves multiplying a variable by itself, often known as "squaring." This terminology comes from the fact that a square's area is equal to its side length multiplied by itself. The Latin term quadratum, which means square, is where the word "quadratic" derives.Three points are used to determine a quadratic function, which has the form f(x) = ax2 + bx + c. A quadratic function can be determined from three points on its graph by finding a, b, and c algebraically. Three equations and three unknowns must be solved in order to do this.

To learn more about quadratic function refer to:

https://brainly.com/question/25841119

#SPJ4

Other Questions
Please help me with this question. use the term planter and tidewater to describe the plantation economy Select the correct location on the image.Which line will result in a compile-time error? Indicate whether the following carbohydrates will give a positive or a negative result in each type of test listed below: Benedicts test, Seliwanoffs test, Fermentation test, Iodine Test, Glucose Fructose Galactose Sucrose Lactose Maltose Amylose Amylopectin Albert has $30 to buy pies and cupcakes for a party. He can buy 2 pies for $8.00 each and wants to use money he has left to buy as many cupcakes as he can Purple hibiscusIn Purple Hibiscus, Adichie characterizes ____ as _______ in order to ___________. For example when ___________ (events from the pages before your text evidence), _____________ writes, ___________ (##). This shows repeat your claim because ___________. Copy from your notes what you thought was so interesting/ why you liked/ hated this piece of text evidence. Write a technical document (at least 500 words in length).Identify the step-by-step instructions needed to operate a tool, design a system, or explain the bylaws of an organization.Include all factors and variables that need to be considered.Use headings, different fonts and other formatting techniques to aid in organization and comprehension. someone help pls!!!!! Evaluate the expression for m = 2 5(m 14) m2 = What was the dream of Martin Luther King Junior explain briefly? True or False: an equilateral triangle is always an acute triangle, but an acute triangle is never an equilateral triangle. True False A fire hose sends 1 000 kg of water per minute against aburning building. The water strikes the building at20.0 m/s and does not bounce back. (a) What is the rateof change of momentum of the water? (b) What forcedoes the building exert on the water? (c) What force doesthe water exert on the building? Kinetic data for the decomposition of Cl2O2 to ClO are summarized in the following table. Cl2O2(g) --> 2 ClO(g) time (microseconds) [Cl2O2] (M) 0 6.60x10^-8 172 5.68x10^-8 345 4.89x10^-8 517 4.21x10^-8 690 3.62x10^-8 862 3.12x10^-8 A) Determine the value of the first-order rate constant. Answer units are microseconds^-1 or (us^-1). B) Determine the half-life for the decomposition of Cl2O2. A student wants to test if giving dogs a toy to play with makes their tail wag more. He gives dog toys to one group, while another group of dogs does not get any toys. He counts the number of times each dog wags their tail. PLEASE HELP ME its sooo many questions Which of the following enzymes catalyzes the transfer of phosphoryl group Irom ATP to glucose? Select one: a. glucoklnase b. glucose-6-phosphatase c. phosphoglucose mutase d.A transfer such as this does not occur in glycolysis. e. phosphoglucose isomerase PLS HELP ME I AM TIMEDProcedural texts use____words or numbers to show the correct sequence of the steps in the procedure. PLS ANSWER ASAP ILL GIVE BRAINLIEST AND A LOT OF POINTS PLEASEEE THANK YOU edward deposited 9000 into a savings account 5 years ago the simple interest rate is 2 how much did edward earn interest What is inelastic demand in economics example?