Mary spent a total of $355.58 for a party. She spent $200.93 on food, plus an additional $30.93 for each hour of the party. How long was the party? A. 5 hours B. 7 hours C. 4 hours D. 6 hours
Answer:
Option A
Step-by-step explanation:
We are here given that Mary spent a total of $ 355.58 for a party , $200.93 on food , and an additional charge of $30.93 for each hour of party .
So the total money spent for staying at party , will be ;
[tex]\longrightarrow \$ 355.58 - \$200.93 [/tex]
[tex]\\\longrightarrow \$ 154.65 [/tex]
We can calculate the no. of hours spent at the party by dividing this amount by the rate of staying per hour at party as ;
[tex]\\\longrightarrow \dfrac{ \$ 154.65}{\$ 30.93 / hr } [/tex]
[tex]\\\longrightarrow 5 \ hrs . [/tex]
Hence she spent 5hrs at the party .
4) Draw a Venn diagram to show these sets:
• The universal set U = {x | - 10 ≤ x ≤ 10, x El}
• N = {x|-10 ≤x≤-1, x El}
• P= {x|1 ≤ x ≤ 10, x El}
●
• E = {x | x = 2a, 1 ≤ a ≤ 5, a El}
I really need help, and I need it ASAP please!!!
The Venn diagram is attached below.
We have four sets. The sets are represented by the alphabets "U", "N", "P", and "E". The universal set is represented by U. The sets are defined as given below.
U = {x | - 10 ≤ x ≤ 10, x ∈ l}
N = {x | -10 ≤x≤-1, x ∈ l}
P = {x | 1 ≤ x ≤ 10, x ∈ l}
E = {x | x = 2a, 1 ≤ a ≤ 5, a ∈ l}
The elements in the universal set "U" are -10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10.
The elements in the set "N" are -10, -9, -8, -7, -6, -5, -4, -3, -2, and -1.
The elements in the set "P" are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10.
The elements in the set "E" are 2, 4, 6, 8, and 10.
We need to draw the Venn diagram. A Venn diagram is a graphic representation of the contrasts and similarities between two concepts. Venn diagrams are sometimes known as logic diagrams or set diagrams.
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what number "x" makes the equation 8^x=2 correct?
Answer:
x = (1/3)
Step-by-step explanation:
8ˣ = 2
8 = 2³
2³ˣ = 2¹
3x = 1
÷3 ÷3
------------
1
x = ------
3
I hope this helps!
At a carnival you win a prize if you get a heads, you must first choose a coin. There is a fair and a biased coin, while choosing each coin is equally likely, the biased coin has a 78% of landing tails. What is the probability of choosing the biased coin if you won a prize.
Probability of choosing the biased coin if you won a prize is 0.30
Let "B" be the event of selecting biased coin and "H" be the event of getting head.
P(B) = 0.5
P(getting head when coin was biased) = 100% - 78%
= 22% = 0.22
Using conditional Probability that biased coin was selected given that you have won the prize that is getting head
we have to calculate ,
P(B | H ) = P(B∩H)/P(H)
here , P(B∩H) = P(biased coin selected and getting head) = 0.5 × 0.22
and P(H) = P(getting head)
P(getting head when coin was biased) + P(getting head when coin was unbiased) = 0.5 × 0.22 + 0.5 × 0.5
putting all together ,
P(B | H ) = P(B∩H)/P(H) = 0.5 × 0.22 / 0.5 × 0.22 + 0.5 × 0.5
cancelling 0.5 from numerator and denominator
= 0.22 / 0.5+ 0.22
= 0.22 / 0.72 = 22/72
=0.30
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-4n+7+2n=1
ANSWER WITH EXPLAINATION
Answer:
n = 3
Step-by-step explanation:
-4n + 7 + 2n = 1
Collect like terms
-2n + 7 = 1
Subtract 7 from both sides
-2n = 1 - 7
Do the math on the right side
-2n = -6
Divide both sides by -2
n = 3
Find two positive numbers for which the product is 196 and the sum of the first plus four times the second is a minimum. ONE of these numbers is B) 14 C) 12 D) 8 E) 7
Minimum number is 33+4*6= 57
Give us two positive numbers, x and y.
196 is the result: x*y = 19
The minimum is the product of the first plus four times the second: x + 4y.
The first equation results in y = 196/x. Put that into the second equation as a replacement:
x + 4y = x + 4(196/x) = x + 784/x
Taking the first derivative now, we can solve for x by setting it to zero.
d(x + 784/x)/dx = 1 - 784/[tex]x^{2}[/tex]
0 = 1 - 784/[tex]x^{2}[/tex]
0 = [tex]x^{2}[/tex]- 784 [[tex]x^{2}[/tex] multiplied on both sides]
784 = [tex]x^{2}[/tex]
[tex]\sqrt{784}[/tex] = [tex]\sqrt{x^{2} }[/tex]
Y = 196/x = 7 since we want a positive integer, hence x = 28
The factors of 196 are 196*1, 99*2, 66*3, 6*33,22*19, and 11*18 as a check.
196 + 4*1 = 200
99 + 4*2 = 107
66 + 4*3 = 78
33+4*6= 57
22 + 4*19 = 98
11 + 4*18=82
In fact, 33+4*6= 57 is minimum.
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Ue Greatet Common Factor (GCF) and the Ditributive Property to write 3550 a a product
By using GCF and distributive Property, it is obtained that
3550 = 5 [tex]\times[/tex] 710 as a product
What is Greatest Common Factor and distributive property?
Greatest Common factor (GCF) of two numbers a and b is the greatest number that divides both a and b.
Distributive property is the property over both addition and multiplication.
If a, b and c are three numbers, then distributive property is given by
[tex]a \times (b + c) = a \times b + a \times c[/tex]
3550 = 3000 + 550
Now,
[tex]3000 = 2\times 2 \times 2\times 3\times 5 \times 5 \times 5\\550 = 2 \times 5 \times 5 \times 11[/tex]
GCF of 3000 and 550 = 5
3550 = 5 [tex]\times[/tex] 600 + 5 [tex]\times[/tex] 110
3550 = 5 [tex]\times[/tex] (600 + 110) [Distributive Property]
3550 = 5 [tex]\times[/tex] 710
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You can buy 3 apples at the quick market for $1.26 you can buy 5 of the same apples at the stop and save for $2.55 witch place is better buy
Answer:
quick market
Step-by-step explanation:
because it more cheaper
Gus is buying juice drinks, x, and snack packs, y, for a school picnic. The system of inequalities models how many of each item Gus needs to buy and how much he can spend. Which of the following points represents a viable solution to the system?
I will give Brainliest to whoever answers
x + y ≥ 150
1.5x + 3.5y ≤ 600
A. (−10, 170)
B. (80, 90)
C. (250, −50)
D. All real whole numbers, with x ≥ 0 and y ≥ 0
The points that represents a viable solution to the system of inequalities include the following:
A. (−10, 170)
B. (80, 90)
C. (250, −50)
How to determine the points for a viable solution to the system?In order to determine which points are true and viable with respect to a solution of the given system of inequalities, we would have to test the each of the points by substituting their values into the inequalities as follows;
For points (-10, 170), we have:
x + y ≥ 150
-10 + 170 ≥ 150
160 ≥ 150 (Viable).
1.5x + 3.5y ≤ 600
1.5(-10) + 3.5(170) ≤ 600
-15 + 595 ≤ 600
580 ≤ 600 (Viable).
For points (80, 90), we have:
x + y ≥ 150
80 + 90 ≥ 150
170 ≥ 150 (Viable).
1.5x + 3.5y ≤ 600
1.5(80) + 3.5(90) ≤ 600
120 + 315 ≤ 600
435 ≤ 600 (Viable).
For points (250, -50), we have:
x + y ≥ 150
250 - 50 ≥ 150
200 ≥ 150 (Viable).
1.5x + 3.5y ≤ 600
1.5(250) + 3.5(-50) ≤ 600
375 - 175 ≤ 600
200 ≤ 600 (Viable).
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Which equations have the same value of x as Three-fifths (30 x minus 15) = 72? Select three options.
18 x minus 15 = 72
50 x minus 25 = 72
18 x minus 9 = 72
3 (6 x minus 3) = 72
x = 4.5
Answer:
Option 3 ) 18x - 9 = 72
Step-by-step explanation:
Algebraic equations:
[tex]\sf \dfrac{3}{5}(30x - 15) = 72\\\\\\[/tex]
Multiply each term of (30x - 15) by 3/5,
[tex]\sf \dfrac{3}{5}*30x - \dfrac{3}{5}*15=72\\\\\\3*6x - 3*3 = 72\\\\18x - 9 = 72[/tex]
The given equation is same as 18x - 9 = 72
What is the value of a?
Enter your answer in the box.
a
25
20
Answer:
the side a is equal to 15.
Step-by-step explanation:
I entered it into my calculator.
please help asap my mom and dad will kill me if i don't have this practice exam done. Liz wanted to buy a new book. When she checked the price last week, it was $16. This week, the same book was listed for $20. Write and solve an equation to show how much the book increased in price.
20 = p − 16; p = $36
20 = p + 16; p = $4
16 + p = 36; p = $20
2p = 20; p = $10
Answer:
Step-by-step explanation:
1. Since the price goes up by whatever number it eventually become 20$ from 16$. SO subtract to get number. 20-16= 4 $
So fitting best...: 20$=p+16;p=4$= TRUE
Answer:20$=p+16;p=4$ or Choice C
PS.Hope you find it helpful!!
Select all the expressions that are equivalent to 8^3/2^3
Evaluate 5 (2)² – 6.
5(2)² - 6 =
Answer:
14
Step-by-step explanation:
Check the file
[tex]\huge\text{Hey there!}[/tex]
[tex]\mathsf{5(2)^2 - 6}[/tex]
[tex]\mathsf{= 5(2 \times 2) - 6}[/tex]
[tex]\mathsf{= 5(4) - 6}[/tex]
[tex]\mathsf{= 20 - 6}[/tex]
[tex]\mathsf{= 14}[/tex]
[tex]\huge\text{Therefore, your answer should be: \boxed{\mathsf{14}}}\huge\checkmark[/tex]
[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]
Jose is wrapping a stack of 100 coins in a paper holder. Each coin is 18 inch thick and has a diameter of
1 inch. How many square inches of paper will Jose need to cover the stack of coins? Use 3.14 for π.
Jose will need 40.82 in² of paper to cover the stack of coins
How to determine the square inches of paper Jose will need to cover the stack of coins?The area in this scenario will be:
A = 2πr² + 2πrh
Where r and h represent the radius of the coins and the height of the coin stack respectively
Given: diameter of coin = 1 inch and thickness = 1/8 inch
radius(r) = diameter/2 = 1/2 inch
Substituting values gives:
A = 2×3.14 × (1/2)² + 2×3.14 ×(1/2)×(100 ×(1/8))
A = 40.82 in²
Note: the correct thickness of the coins should be 1/8 in
Therefore, the area of paper Jose will need to cover the stack of coins is 40.82 in²
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Enter your answer and show all the steps that you use to solve this problem.
What is the vertex form of the equation?
y=-z²+12z-4
The vertex form of the equation y = -z² + 12z -4 is y = -(z - 6)² + 32.
What is a parabola?A parabola's vertex is the location where the curve turns steepest. If a parabolic function has the shape of a 'U', it has a minimum value; otherwise, it has a maximum value. The parabola's axis of symmetry intersects with the parabola at its vertex.
For any parabola Ax² + Bx + C, the x-coordinate of the vertex is given by -B/(2A).
So, according to our question
A = -1
B = 12
C = -4
So, z = - 12/2(-1)
z = - 12/- 2
z = 6
Plug the value in the equation
y = - (6)² + 12(6) -4
y = -36 +72 -4
y = 32
So, the vertex of the parabola will be at (6, 32) and the vertex form of the equation y = -z² + 12z -4 is y = -(z - 6)² + 32.
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PLEASE HELP ASAP WILL GIVE ANYTHING
Spin a spinner with three equal sections colored red, white, and blue. What is P(green)?
0%
100%
33%
66%
Answer:
Step-by-step explanation:
Ok:
Since percent can only add up to 100%, the sum must be no longer over 100%
There is no green on the spinner only red, white, and blue!
This means that 0 out of 100 percent is available for green!
Answer: 0%
The solution is Option C.
The probability of getting a green colored section on the spinner is given by the equation P ( green ) = 33 %
What is Probability?The probability that an event will occur is measured by the ratio of favorable examples to the total number of situations possible
Probability = number of desirable outcomes / total number of possible outcomes
The value of probability lies between 0 and 1
Given data ,
Let the probability of getting a green colored section on the spinner be represented as P ( green )
Now , the equation will be
The number of sections on the spinner = 3 sections
The 3 sections are = { red , white , green }
So , probability of getting a green colored section P ( green ) = 1 / number of sections on the spinner
Probability of getting a green colored section P ( green ) = 1/3
Probability of getting a green colored section P ( green ) = 0.33
Probability of getting a green colored section P ( green ) = 33 %
Therefore , the value of P ( green ) is 33 %
Hence , the probability is 33 %
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Please help!!
5x -10y = 10
x + 2y = -18
(Enter the solution like this: ( , ) )
The value to the system of equations is (-10, -4)
How to determine the solution to the system of equations?In this case, the system of equations is given as
5x -10y = 10
x + 2y = -18
Make x the subject in the second equation
So, we have the following representation
x = -2y - 18
Substitute x = -2y - 18 in the equation 5x -10y = 10
So, we have
5(-2y - 18) -10y = 10
Open the brackets
This gives
-10y - 90 - 10y = 10
Evaluate the like terms
-20y = 80
Divide by -20
y = -4
Recall that x = -2y - 18
So, we have
x = -2 * -4 - 18
Evaluate
x = -10
Hence, the solution is (x, y) = (-10, -4)
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if the probability of a machine producing a defective part is 0.05, what is the probability of finding exactly 4 defective parts from a sample of 100? (assume that the process follows a binomial distribution.)
There is a probability of 22% that exactly 4 defective parts will be found in a sample of 100.
Probability of a machine producing a defective part is 0.05,
p = 0.05
q = 1 - p = 1 - 0.05 = 0.95
n = 100
P(x) = ⁿCₓ pˣqⁿ⁻ˣ
x = 4
P(4) = ¹⁰⁰C₄(0.05)⁴(0.95)⁹⁶
P(4) = 0.215569
= 0.2156
0.2156 is the probability of finding exactly 4 defective parts from a sample of 100.
The probability of defective parts is the likelihood that a part will be defective. This can be due to a variety of factors, such as poor quality control, incorrect manufacturing process, or use of sub-standard materials. A high probability of defective parts can lead to serious problems, such as faulty products, safety hazards, and financial losses.
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If f(x)=2x^3-6x^2-16x-20f(x)=2x *3 −6x *2−16x−20 and f(5)=0, then find all of the zeros of f(x)f(x) algebraically.
The zeros of the cubic function f(x) = 2x³ - 6x² - 16x - 20 are given as follows:
x = 5, x = -1 + i, x = -1 - i.
How to obtain the solutions to the equation?The equation is defined by the rule presented as follows:
f(x) = 2x³ - 6x² - 16x - 20.
One solution for the equation is given as follows:
x = 5.
Because f(5) = 0.
Then (x - 5) is a linear factor of the function f(x), which can be written as follows:
2x³ - 6x² - 16x - 20 = (ax² + bx + c)(x - 5).
This is because the product of a linear function and a quadratic function results in a cubic function.
Now we expand the right side to begin finding the coefficients of the quadratic function that we are going to solve to find the remaining zeros:
2x³ - 6x² - 16x - 20 = = ax³ + (b - 5a)x² + (c - 5b)x - 5c.
Then these coefficients are obtained comparing the left and the right side of the equality as follows:
a = 2.-5c = -20 -> c = 4.b = -6 + 5a = 4.Hence the equation is:
2x² + 4x + 4.
Using a quadratic equation calculator, the remaining zeros are given as follows:
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Anna is working two summer jobs, making $9 per hour washing cars and $12 per
hour landscaping. Last week Anna worked a total of 7 hours and earned a total of
$78. Determine the number of hours Anna worked washing cars last week and the
number of hours she worked landscaping last week.
By solving a system of equations we will see that Anna works 2 hours washing cars and 5 hours landscaping.
How to determine the number of hours in each job?
First, we need to define the variables that we will be using, these are:
x = number of hours washing cars.y = number of hours landscaping.We know that she works 7 hours in total and earns $78 in total, so we can write the system of equations:
x + y = 7
x*$9 + y*$12 = $78
Isolating x on the first equation we get:
x = 7 - y
Replacing this on the other equation we get:
(7 - y)*$9 + y*$12 = $78
$63 - $9*y + $12*y = $78
$63 + $3*y = $78
$3*y = $78 - $63
$3*y = $15
y = $15/$3 = 5
Then the value of x is:
x = 7 - y = 7 - 5 = 2
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If the perimeter of the window is 28 feet, find the exact value of x (in ft) so that the greatest possible amount of light is admitted.
the exact value of x, so that the greatest possible amount of light is admitted is 3.92 ft.
let x represents the radius of a semicircle, thus the width of the rectangle = 2x, length be y.
perimeter of the rectangular window = πx + 2y + 2x = x(π +2) + 2y
it is given that the perimeter is 28 ft.,
28 = x(π +2) + 2y
y = 28 - x(π +2) / 2
the area of the window A = 1/2 πx² = 2yx ( area of semicircle + area of rectangle)
A = 1/2 πx² + 2x [(28 - x(π +2) / 2] (Substituting the value of y)
A = 1/2 πx² + 28x - πx² - 2x²
A = 28x - x² ( 2 + π/2 )
The maximum value of x is when dA/dx = 0
A' = 28- 2x ( 2 + π/2 )
2x ( 2 + π/2 ) = 28
x ( 2 + π/2 ) = 14
x = 3.92 ft
hence the value of x so that the greatest possible amount of light is admitted is 3.92 ft.
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(complete question)
A Norman window has the shape of a rectangle surmounted by a semicircle. (Thus the diameter of the semicircle is equal to the width of the rectangle. See the figure below.) If the perimeter of the window is 28 ft, find the value of x so that the greatest possible amount of light is admitted.
make r the subject of formula in V= pie h square(r-h/3)
When r is made the subject of the formula we have; V + πh^3/3πh^2
What is the subject of a formula?The term subject of a formula has to do with the variable that we are trying to obtain in the equation. Hence the subject of the formula must be written on the left hand side of the mathematical equation.
We have;
V = πh^2(r - h/3)
We open the bracket;
V = πrh^2 - πh^3/3
Adding πh^3/3 to both sides, we have;
V + πh^3/3 = πrh^2
Then we divide both sides by πh^2
r = V + πh^3/3/πh^2
r = V + πh^3/3πh^2
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Transform y=-2x + 5 into an equivalent equation that is in standard form
Answer: The standard form of a linear equation is Ax+By=C. To change an equation written in slope-intercept form (y=mx+b) to standard form, you must get the x and y on the same side of the equal sign and the constant on the other side. Use inverse operations to move terms.
Step-by-step explanation:
Which of the following are solutions to the equation below?
Check all that apply.
(2x+3)² = 10
x= √2/2
A. x=
□ B. x-10-3
2
C. x= -√/10 +
5 + 2/1/2
☐ D. x =
-10-3
2
<= -√
2
☐ E. x = -
32
OF. x= √10 +
332
The solutions for the equation (2x+3)² = 10 is:
x=√10-3/2x=-√10-3/2Given:
the equation is:
(2x+3)² = 10
we need to solve the following equation.
⇒ (2x+3)² = 10
taking square roots on both sides.
⇒ √(2x+3)² = √10
⇒ 2x+3=±√10
Now solving:
2x+3=√10 and 2x+3=-√10
2x=√10-3 and 2x=-√10-3
x=√10-3/2 and x=-√10-3/2
Hence we get the solutions of the given equation.
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An open-top box is to be constructed from a sheet of tin that measures 32 inches by 18 inches by cutting out squares from each corner as shown and then folding up the sides. Let V(x) denote the volume of the resulting box.
The answer of resulting box volume = 576[tex]x[/tex] - 100[tex]x^{2}[/tex] - 4[tex]x^{3}[/tex]
What are example and volume?
The volume of an object serves as a gauge for its capacity. For instance, if the brim of a cup can hold 100 ml of water, that cup is said to have a 100 ml capacity.. Another way to quantify volume is how much room a three-dimensional object occupies.
Volume = length x breath x height
length = 32-2[tex]x[/tex]
Breath = 18-2[tex]x[/tex]
Height = [tex]x[/tex]
Volume = (32-2[tex]x[/tex]) x (18-2[tex]x[/tex]) x ([tex]x[/tex])
= 576 - 64[tex]x[/tex] - 36[tex]x[/tex] - 4[tex]x^{2}[/tex] x ([tex]x[/tex])
= 576[tex]x[/tex] - 100[tex]x^{2}[/tex] - 4[tex]x^{3}[/tex]
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I need to find the slope and the y-intercept please help
Answer: 30
Step-by-step explanation:
1. You find the slope by picking 2 points and dividing the change in the y-axis by the change in the x-axis. (Time is ALWAYS x)
(50-40)/40-20
(10)/20)
1/2
SLOPE=1/2
2. You find the y-intercept by picking a point, and plugging them into your equation, and solving for b.
(I will be using the point (20,40) )
40=1/2(20)+b
40=10+b
b=30
Y-INTERCEPT=30
9. A contractor is pouring a rectangular concrete slab with dimensions of 16 feet by 30
feet. To ensure that the sides of the slab form 90° angles, how many feet should
each diagonal measure?
If each sides of the slab form 90° angles, The number of feet that
each diagonal measure is 34 feet.
How to find the diagonal feet?Using Pythagoreans theorem formula to find the diagonal feet
D² =L² + W²
Where:
D = Diagonal
L= Length = 16 feet
W = Width = 30
Let plug in the formula
D² = 16² + 30²
D² = 256 + 900
D=√1156
D= 34 feet
Therefore the diagonal measure 34feet
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Identify the solution of the inequality |9m| + 40 > 4 and the graph that represents it.
Answer:
B) All real numbers===========================
GivenInequality |9m| + 40 > 4Solution|9m| + 40 > 4|9m| > - 40 + 4|9m| > - 36|m| > - 4Since absolute value is never negative, this inequality is correct for any value of m.
Correct answer choice is B.
Answer:
All real numbers.
Step-by-step explanation:
The bars either side of an expression or a value are the absolute value symbol. "Absolute value" means how far a value is from zero. Therefore, the absolute value of a number is its positive numerical value.
Given inequality:
[tex]|9m|+40 > 4[/tex]
Subtract 40 from both sides to isolate the absolute value on one side of the equation:
[tex]\implies |9m|+40-40 > 4-40[/tex]
[tex]\implies |9m| > -36[/tex]
As the absolute value of a number or expression is its positive numerical value:
[tex]\implies |9m| \geq 0[/tex]
Therefore, as 9m is always greater than or equal to zero, it will always be greater than -36, regardless of the value of m.
Therefore, the solution of the given inequality is all real numbers.
the student council sold $661$ t-shirts, some at $\$10$ and some at $\$12$. when recording the number of t-shirts they had sold at each of the two prices, they reversed the amounts. they thought they made $\$378$ more than they really did. how many t-shirts actually were sold at $\$10$ per shirt?
The student council sold $273$ t-shirts were sold at $\$10$ per shirt.
Let $x$ be the number of shirts sold at $\$10$
Let $y$ be the number of shirts sold at $\$12$
$x+y=661$
$10x+12y=3780$
$x=y+101$
$10y+12y=3780$
$22y=3780$
$y=172$
$x=172+101$
$x=273$
Hence $273$ t-shirts were sold at $\$10$ per shirt.
If they sold $661$ t-shirts in total, and they made a mistake when recording the amount of t-shirts sold at each price, then they actually sold more t-shirts at $\$10$ than they thought. This means that they thought they sold fewer t-shirts at $\$10$ than they actually did.
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