The sum of the two complex numbers will give:
(-4 + i) + (10 - 5i) = 6 - 4i
So the correct option is the third one.
How to add two complex numbers?Let's assume we have two complex numbers which are:
A = a + bi
B = c + di
The sum between these two complex numbers is:
A + B = (a + bi) + (c + di)
Taking i as a common factor we can rewrite:
(a + bi) + (c + di) = a + c + (b + d)i
And that is the general sum.
Here we want to solve:
(-4 + i) + (10 - 5i)
Again, if we take i as a common factor we can rewrite:
-4 + 10 + (1 - 5)*i
6 - 4i
So the correct option is the third one.
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referring to question 28, what is the value of a difference such that 60% of the age differences are less than it?
A gap of 2.03 years has a value such that 60% of age disparities are smaller than it.
what is age difference ?If the age is expressed as a ratio, such as p:q, then qx and px are taken into account as the age. If you assume that you are x years old now, then n times that number is (xn) years. If you're assuming that x is the current age, then 1/n of that number will equal (x/n) years.
calculation
Let's say there is an age difference of x and y,
in which case the answer to question 28 should be 2.03 years:
(x-y)*60/100.
A gap of 2.03 years has a value such that 60% of age disparities are smaller than it.
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What i the value?
1/4 - 1/2 ( - 4/7)
Anwer
1) - 1 5/16
2) - 3/7
3) 3/7
4) 1 5/16
Answer:
None of these
Step-by-step explanation:
[tex]\frac{1}{4}+\frac{1}{2} \cdot \frac{4}{7}=\frac{1}{4}+\frac{4}{14}=\frac{1}{4}+\frac{2}{7}=\frac{7+8}{28}=\frac{15}{28}[/tex]
how do you solve this?
According to Euclidean geometry, the geometric system consisting in isosceles triangle has an angle x whose measure is equal to 74°.
How to solve a variable in an isosceles triangle
In this problem we find a geometric system consisting in a triangle, where two sides are congruent and the measure of an angle equals 74°.
According to Euclidean geometry, a triangle represented by the geometric system, with such features represents an isosceles triangle, that is, a triangle with two congruent sides and two congruent angles between the base side and each of the two congruent sides. Thus:
m ∠ x = 74°
x = 74°
Therefore, the measure of angle x, opposite to the angle whose measure is 74°, must be also equal to 74°.
The measure of angle x associated with the geometric system consisting in an isosceles triangle is equal to 74°.
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which of the following statements is a proposition? (a) get me a glass of milk (b) god bless you! (c) what is the time now? (d) the only odd prime number is 2
The proposition ststement is: the only prime number that is odd is 2.
The correct answer is an option (d)
In this question we have been given some statements.
we need to identify the proposition statement.
We know that a proposition is a declarative statement. In mathematics proposition gives a clear inference of whether a sentence is true or false. The proposition statement cannot be stated in two ways. The statement must be either correct or incorrect.
a) get me a glass of milkshake.
It is a commanding statement.
b) god bless you!
It is a type of optative statement.
c) what is the time now?
It is a question sentence.
d) the only odd prime number is 2.
It is a false proposition statement.
Therefore, option (d) is a proposition statement.
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Given the following exponential function, identify whether the change represents
growth or decay, and determine the percentage rate of increase or decrease.
y = 10(1.01)
The given exponential function represents the growth in the function. The percentage of growth (increase) is 1%.
What is the exponential growth function?An exponential growth function is a function where the quantity increases slowly and after some time, it increases rapidly.
It is represented by the formula,
y = a(1 + r)ˣ
Here the term 'a' is the initial amount of the quantity, the term 'r' is the rate of increase and the term 'x' is the period.
Calculation:The given exponential function is y = 10(1.01)ˣ
Here we can write the function as
y = 10(1.01)ˣ
⇒ y = 10(1 + 0.01)ˣ
Since 1.01 > 1, it is an exponential growth function.
So, when comparing with the formula, we get the rate of increase,
r = 0.01
Converting it into fractions, we get 1/100
Then, the percentage rate of increase is 1%.
Therefore, the given exponential function grows with a rate of 1% increase.
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See the attached image.
The value of x will be 1.17 inches and the maximum volume of the box is 1.6 cubic inches.
What is volume?Volume is a measurement of three-dimensional space that is occupied. It is frequently numerically quantified using SI-derived units or various imperial or US customary units. The definition of length is linked to the definition of volume.
Given that the rectangular box is made from cardboard the thickness is x.
The length of the box will be,
L = 4.5 - 3x
The width of the box will be,
W = 4 - 2x
The thickness of the box is,
H = x
The volume of the box will be calculated as,
V = ( 4.5 - 3x) ( 4 - 2x ) (x)
V = ( 4.5 - 3x) ( 4 - 2x ) (x)
V = ( 18 - 12x - 9x + 6x² ) x
V = 6x³ -21x² + 18x
For maximum volume differentiate the volume with respect to x and get the value of x,
dV / dx = d / dx ( 6x³ -21x² + 18x ) = 0
d / dx ( 6x³ -21x² + 18x ) = 0
18x² - 42x + 12 = 0
3x² - 7x + 6 = 0
Solve the above quadratic equation as,
x = [ -b ±√(b² - 4ac) ] / 2a
x = [ -7 ± √ (-7² - 4 x 3 x 6 ) ] / ( 2 x 3 )
x = 1.17
The value of x is 1.17 inches by solving the above quadratic equation. The maximum volume will be calculated as,
V = 6x³ -21x² + 18x
V = 6(1.17)³ -21(1.17)² + 18(1.17)
V = 9.6 - 28.7 + 21.06
V = 1.96 cubic inches
The maximum volume is 1.96 cubic inches and the value of x is 1.17 inches.
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2. Divide. Write the answer in simplest
form.
6 2/3 divided by 4 1/5
Answer:
100/63
Step-by-step explanation:
6 2/3 ÷4 1/5
20/3÷21/5
20/3×5/21
1 37/63 or 100/63 or 1.587301587
so the answer is one (whole number) thirty seven over sixty three
A website offers a coupon to 50\%50%50, percent of its visitors, selected at random, each day. Yasemin visits the website for 444 days. What is the probability that yasemin will not be offered a coupon on at least one of the days she visits the website? round your answer to the nearest hundredth. P(\text{at least one day without coupon})=p(at least one day without coupon)=p, left parenthesis, start text, a, t, space, l, e, a, s, t, space, o, n, e, space, d, a, y, space, w, i, t, h, o, u, t, space, c, o, u, p, o, n, end text, right parenthesis, equals.
The probability that Yasmin will not be offered a coupon on at least one of the days she visits the website will be;
⇒ 0.9375
What is mean by Probability?The term probability refers to the likelihood of an event occurring
Given that;
The probability that a visitor is offered a coupon (p) = 50%
Now,
Since, The probability that a visitor is offered a coupon (p) = 50%
Hence, The probability that he gets coupon all 4 days is,
⇒ p (4) = p⁴
⇒ p (4) = (50%)⁴
⇒ p (4) = 0.0625
Hence, By using the complement rule, the probability that he is not offered a coupon at least one day is,
⇒ p' = 1 - 0.0625
⇒ p' = 0.9375
Thus, The probability that Yasmin will not be offered a coupon on at least one of the days she visits the website = 0.9375
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PLEASE THIS IS SERIOUS
Solve for x
A) a wooden block is formed in a the shape shown by cutting a right rectangular solid from a larger one. What is the volume of the block
B) check your calculations by using a second method to solve the problem
The volume of the rectangular block in this problem is given as follows:
1300 cm³.
How to obtain the volume of the block?The block is a rectangular prism, hence it's volume is given by the multiplication of it's dimensions, as follows:
V = length x width x height.
The dimensions for this block are given as follows:
Length: 16 cm.Width: 10 cm.Height: 10 cm.However, there is a small rectangular block that is removed from the prism, with the dimensions given as follows:
Length: 6 cm.Width: 10 cm.Height: 5 cm.Hence the volume of the rectangular block can be calculated as follows:
V = 16 x 10² - 6 x 5 x 10 = 1300 cm³.
(total volume subtracted by the removed volume from the empty space at the middle).
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miguel is mixing up a salad dressing. regardless of the number of servings, the recipe requires that 58 of the finished dressing mix be olive oil, 14 vinegar, and the remainder an even mixture of salt, pepper and sugar. if miguel accidentally doubles the vinegar and forgets the sugar altogether, what proportion of the botched dressing will be olive oil?
44 is the proportion of the botched dressing will be olive oil.
Given, Miguel is mixing up a salad dressing. regardless of the number of servings,
the recipe requires that 58 of the finished dressing mix be olive oil, 14 vinegar, and the remainder an even mixture of salt, pepper and sugar. if he accidentally doubles the vinegar and forgets the sugar altogether,
we have to find the proportion of the botched dressing that will be olive oil.
first we will find the amount of the even mixture of salt, pepper and sugar.
as, olive oil + vinegar + even mixture of salt, pepper and sugar = 100
58 + 14 + mixture of salt, pepper and sugar = 100
mixture of salt, pepper and sugar = 100 - 72
mixture of salt, pepper and sugar = 28
if he mixed doubles of the vinegar i.e. 28 then olive oil be,
x + 28 + 28 = 100
x = 100 - 56
x = 44
Hence, 44 is the proportion of the botched dressing will be olive oil.
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Answer question #8
Give a short answer responding the question that’s being asked
The response written in the box isn’t correct so I need help
The conclusion is that the angle which measures 120° is not Acute angle.
What are angles ?The construction of an angle is a type of geometric shape made by connecting two rays at their termini. Three letters that make up the form of the angle can alternatively be used to symbolise the angle, with the middle letter indicating the location of the angle (i.e.its vertex). Greek characters such θ, α, β, etc. are frequently used to denote angles.
In geometry, there are mainly six different kinds of angles. All angles have the following names and characteristics:
The acute angle ranges from 0° to 90°.The obtuse angle ranges from 90° to 180°.Right Angle: The angle that is 90 degrees precisely.Direct Angle: the angle that is exactly 180 degreesReflex Angle: The angle between 180 degrees and 360 degrees that is bigger than 180 degrees.360-degree full rotation: The whole rotation of an angle.Angle B measures 120°.
Here the angle is more than 90° so the angle is not acute.
The conclusion is that the angle which measures 120° is not Acute angle.
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a student needs 11 more classes to graduate. if she has met the prerequisites for all the classes, how many possible schedules for next semester could she make if she plans to take 4 classes?
We can conclude that the number of possible schedules for next semester could she make is 7920.
In more mathematical terms, the factorial of a number (n!) is equal to
n(n-1). For example, if you want to calculate the factorial for four, you would write: 4! = 4 x 3 x 2 x 1 = 24.
Given that,
The student needs 11 more classes to graduate.
And, possible schedules for next semester could she make if she plans to take 4 classes
Based on the given expression, the calculation is as follows:
The combination formula is given to be:
[tex]n_{C} _{r} =\frac{n!}{r!(n-r)!}[/tex]
= [tex]11_{C} _{4}[/tex] ! * 4 !
= [tex]\frac{11 !}{4!(11-4)!}[/tex] * 4 !
= [tex]\frac{11!}{4!7!}[/tex] * 4 !
= [tex]\frac{11*10*9*8*7*6*5*4*3*2*1}{4*3*2*1*7*6*5*4*3*2*1}[/tex] * 4 !
We can cancel the coefficients,
= [tex]\frac{11*10*9*8}{4*3*2*1}[/tex] * 4 !
= [tex]\frac{7920}{24}[/tex] * 4 !
= 330* 4 !
= 330 * 4*3*2*1
= 7920
Therefore,
We can conclude that the number of possible schedules for next semester could she make is 7920.
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1-36) what is the sum of 2 + (1/5 + 1/5² + 1/5³ +...,.. +... 1/(5 to power n) ..)
help how
Answer:
[tex]\displaystyle \frac{9}{4}[/tex]
Step-by-step explanation:
[tex]\displaystyle 2 + (\frac{1}{5^1} + \frac{1}{5^2} + \frac{1}{5^3} + ... + \frac{1}{5^n} )[/tex]
The second term of this sum is an Infinite Geometric Progression
To find the sum of an Infinite Geometric Progression,
- Find the first term ( 1/5 ) of the progression and call it a
- Find the common ratio, (divide any term by it's predecessor. i.e [tex]\displaystyle \frac{\frac{1}{5^2} }{\frac{1}{5} } = \frac{5}{5^2} = \frac{1}{5}[/tex]) and call it r
Finding the sum of given Geometric Progression:
Sum of Infinite GP: [tex]\displaystyle \frac{a}{1-r}[/tex]
Plugging our values in this equation, we get:
Sum of Geometric Progression = [tex]\displaystyle \frac{\frac{1}{5} }{1 - \frac{1}{5} } = \frac{\frac{1}{5} }{\frac{5 - 1}{5} } = \frac{1}{4}[/tex]
Adding to find the actual answer:
[tex]\displaystyle (\frac{1}{5^1} + \frac{1}{5^2} + \frac{1}{5^3} + ... + \frac{1}{5^n} ) = \frac{1}{4}[/tex]
[tex]\displaystyle 2 + (\frac{1}{5^1} + \frac{1}{5^2} + \frac{1}{5^3} + ... + \frac{1}{5^n} ) = 2 + \frac{1}{4}[/tex]
[tex]\displaystyle 2 + (\frac{1}{5^1} + \frac{1}{5^2} + \frac{1}{5^3} + ... + \frac{1}{5^n} ) = \frac{9}{4}[/tex]
luka is making lemonade to sell at a school fundraiser. his recipe requires 4 times as much water as sugar and twice as much sugar as lemon juice. he uses 3 cups of lemon juice. how many cups of water does he need?
Luka will require 24 cups of water to make lemonades as calculated from the data given.
The quantity of sugar which he use is twice the amount of lemon which he us ,
= 2 x 3 = 6
and ,
as we know the amount of water is 4 times as much as lemon juice
Therefore, amount of water
= 4 * 6
= 24
A quantity in a Maths equation is a number or variable plus any algebraic combination of additional quantities. In an equation like x + 6 = 15, four values are represented.
A quantity can be described as the amount of something or how much of it there is. Quantity can also be used to refer to the size of something (its magnitude), whether in terms of numbers, units of measurement, or just relative size.
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Help meee please !!!???
Answer:
Step-by-step explanation:
it is c
Select the number of the algebraic expression for "The room capacity does not exceed 250".
c>250
c≥250
c<250
c≤250
c≠250
The algebraic expression for "The room capacity does not exceed 250" is D. c≤250
How to illustrate the inequality?Inequalities are created through the connection of two expressions. It should be noted that the expressions in an inequality aren't always equal. Inequalities implies that the expressions are not equal. They are denoted by the symbols ≥ < > ≤.
It should be noted that "the room capacity does not exceed 250" simply means it should be less than or equal to 250. This will be c≤250.
In conclusion, the correct option is D.
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PLEASE HELP ME!!!!!! THIS IS DUE ON FRIDAY!!!!!! (There is another part)
Answer:
it's c trust me I had the same problem
What is the cubic polynomial with zeros (3,0), (-6,0), and (1,0)?
(Question 15)
Answer:
D
Step-by-step explanation:
when we have the zeroes, we can build the polynomial by multiplying factors that will turn the functional value to 0 at exactly these points.
f(x) = (x - 3)(x + 6)(x - 1)
we don't need to do the full multiplications to see that the constant term of the polynomial is the result of the multiplication of all 3 constant terms of the factors :
-3 × +6 × -1 = +18
and therefore, D is the correct answer (as it is the only answer option with +18 as constant term).
What is the cubic polynomial with zeros (3,0), (-6,0), and (1,0)?
Question 15
The cubic polynomial with zeros (3,0), (-6,0) and (1,0) is given as follows:
D. x³ + 2x² - 21x + 18.
How to obtain the cubic polynomial?We are given the zeros of the polynomial, which then can be obtained using the Factor Theorem.
The zeros of the polynomial are given as follows:
x = 3, x = -6, x = 1.
Then, applying the Factor Theorem, considering a leading coefficient of 1, the polynomial is given as the product of it's linear factors as follows:
(x - 3)(x + 6)(x - 1)
(x² + 3x - 18)(x - 1)
x³ + 2x² - 21x + 18.
Meaning that option D is correct.
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Find the surface area 5 4 7 6 8 triangular
The surface area of the triangular prism is 136 square units
How to determine the surface areaFrom the question, we have the following parameters that can be used in our computation (see attachment):
Rectangles (2) = 7 units by 5 unitsRectangles (1) = 7 units by 6 unitsTriangles (2) = 4 units by 6 unitsThe surface area of the triangular prism is the sum of the areas of the above shapes
So, we have
Surface area = 2 * area of rectangle 1 + 1 * area of rectangle 2 + 2 * area of triangle 1
Substitute the known values in the above equation, so, we have the following representation
Surface area = 2 * 7 * 5 + 1 * 7 * 6 + 2 * 0.5 * 4 * 6
Evaluate
Surface area = 136
Hence, the surface area is 136 square units
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Find two consecutive positive integers such that the square of the first decreased by 21 equals 6 times the second
The given two consecutive positive integers are 9 and 10.
What is an integer?It is a whole number that can be positive, negative, or zero.
Let consider x and x+1 as two consecutive positive integers.
Given that,
[tex]x^{2} -21=6(x+1)[/tex]
[tex]x^{2} -6x-27=0[/tex]
It can be written in fractional form like,
(x-9)(x+3)=0
so the values of x are 9 and -3.
Here, only positive integers are considered.
Hence 9 and 10 are the two consecutive positive integers.
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Find the volume of the pyramid.
Answer:
180 ft^3
Step-by-step explanation:
volume of the pyramid = (1/3)(area of base) (height)
v= 1/3×(10×12÷2)×(9)
= 180 ft^3
Answer:
answer on the picture.....
Which ordered pair is a solution of the
equation?
-3x + 5y = 2x + 3y
Answer:
Solve the equation for [tex]{y}[/tex].
[tex]y=\frac{5x}{2}[/tex]
Choose any value for [tex]{x}[/tex] that is in the domain to plug into the equation.
Choose [tex]{0}[/tex] to substitute in for [tex]{x}[/tex] to find the ordered pair.
[tex]{(0,0)}[/tex]
Choose [tex]{1}[/tex] to substitute in for [tex]{x}[/tex] to find the ordered pair.
[tex](1,\frac{5}{2})[/tex]
Choose [tex]{2}[/tex] to substitute in for [tex]{x}[/tex] to find the ordered pair.
[tex]{(2,5)}[/tex]
These are three possible solutions to the equation.
[tex]{(0,0),}[/tex] [tex](1,\frac{5}{2} )[/tex], [tex]{(2,5)}[/tex]
What is the value of 5/9 ÷ 5/6? Responses
Answer:
2/3 or 0.667
Step-by-step explanation:
5/9 ÷ 5/6
5/9 * 6/5
1/3 * 2/1 (after cancelling off)
= 2/3
please help me I don’t get this
The operations between functions are:
a) h(f(3)) = 5
b) (f×g)(4) = -8
c) f( g(h(0))) -1
How to operate with functions?
The first thing we want to find is a composition, we want to find:
h(f(3))
That means that we need to evaluate h(x) in f(3), look at the graph and you can see that f(3) = -4
Replacing that we get:
h(f(3)) = h(-4)
And on the graph, we can see that h(-4) = 5
then h(f(3)) = 5
b) Now we have the product:
(f×g)(4) = f(4)*g(4)
Again, looking at the graph:
f(4) = -4
g(4) = 2
Then:
(f×g)(4) = f(4)*f(4)
(f×g)(4) = -4*2
(f×g)(4) = -8
c) Finally we have other composition:
f( g(h(0)))
So we have 2 compositions, first we find:
h(0) = 5
f( g(h(0))) = f(g(5))
Then:
g(5) = 0
f( g(5)) = f(0)
Finally, look at the graph and you can see that f(0) = -1
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A triangle with coordinates (1,1) (4,2) (3,5) is translated three units down and five units to the left
A triangle with coordinates (1,1) (4,2) (3,5) is translated three units down and five units to the left. New coordinates will be (-4,-2), (-1,-1),(-2, 2).
Define translation.A translation is a geometric change in Euclidean geometry that involves moving each point in a figure, shape, or space by the same amount in one direction. A translation can also be thought of as moving the origin of the coordinate system or as adding a constant vector to each point.
Given
A triangle with coordinates (1,1) (4,2) (3,5)
The value of a coordinate is impacted by translations left or right but not by translations up or down or left or right.
We multiply all of the numbers by 3 since we are translating the entire triangle down three units.
Additionally, we are converting the entire triangle to left-to-right units of five, thus we will multiply all values by 5.
A = (1 - 5, 1 - 3)
B = (4 - 5, 2 -3)
C = (3 - 5, 5 - 3)
New coordinates will be:
A = (-4,-2)
B = (-1,-1)
C = (-2, 2)
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cross-tabulation can only be used for two variables; each variable must have well-defined labels. true false
The statement "cross-tabulation can only be used for two variables; each variable must have well-defined labels " is false
The cross tabulation is defined as the tool that is used in statistics to categorical data. We can also says that that present the results of the entire group of respondents
The given statement is "cross-tabulation can only be used for two variables; each variable must have well-defined labels "
The cross tabulation method can be used to represent two or more variables. The cross tabulation table has x axis as one variable and y axis as another variables
The cross tabulation can be used for two or more variables
Therefore, the the given statement is false
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Complete the equation of the line whose yyy-intercept is (0,-1)(0,−1)left parenthesis, 0, comma, minus, 1, right parenthesis and slope is 444.
The complete equation in the slope-intercept form is y = 4x-1.
What is a slope?In mathematics, a line's slope, also known as its gradient, is a numerical representation of the line's steepness and direction.
If a line passes through two points (x₁ ,y₁) and (x₂, y₂) ,
then the equation of line is
y - y₁ = (y₂- y₁) / (x₂ - x₁) x (x - x₁)
To find the slope;
m = (y₂- y₁) / (x₂ - x₁)
So, the equation is,
y - y₁ = m (x - x₁)
And the standard form of the slope-intercept form:
y = mx+b,
where m is the slope and b is the y-intercept.
From the question, we have
m = 4 and coordinates of b is (0, -1).
So, the equation is,
y + 1 = 4 (x - 0)
y +1 = 4x
y = 4x-1
Therefore, the equation is y = 4x-1.
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ayden deposits $2000 into a savings account with an annual interest rate of 3%. If he makes no further deposits or withdrawals, which graph shows the growth of his account balance?
$2,060.00 is the entire amount accrued from simple interest on a principal of $2,000.00 at a rate of 3% per year for 1 years, including principal and interest.
How to resolve our equation?Ayden deposits $2000 into a savings account with an annual interest rate of 3%.
To calculate simple interest, multiply the daily interest rate by the principle and the number of days between payments. Consumers that make on-time or early monthly loan payments benefit from simple interest.
A = $2,060.00
I = A - P = $60.00
A is equal to P(1 + rt).
First, convert R percent to r a decimal; for example, R/100 is 3%/100, or 0.03 per year.
A = 2000(1 + (0.03 × 1)) = 2060 \sA = $2,060.00
$2,060.00 is the entire amount accrued from simple interest on a principal of $2,000.00 at a rate of 3% per year for 1 years, including principal and interest.
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