Answer:
-6xy - 16x -24y -64
Step-by-step explanation:
(2x+8)(-3y-8) =
To find the answer,
First multiply, the first number on both sides,
2x * -3y = -6xy
Then the first number on the left side and the second number on the right side,
2x * -8 = -16x
Then the second number on the left side and the first number on the right side,
8 * -3y = -24y
Then the second number on the left side and the second number on the right side,
8 * -8 = -64
Now add all the answers,
-6xy -16x -24y -64
Answer:
-6xy-16x-24y-64
Step-by-step explanation:
(2x+8)(-3y-8)
Foil
First 2x*-3y = -6xy
outer -8*2x = -16x
inner -3y *8 = -24y
last -8*8 = -64
Add them together
-6xy-16x-24y-64
the number of states that entered the union in 1889 was half the number of states "s" that entered in 1788. which expression shows the number of states that entered the union in 1889
Answer:
x = s/2
Step-by-step explanation:
● s states have joined the union in 1788
● half of s have joined in 1889
Let x be the number of states that have joined in 1889
● x = (1/2)× s
● x = s/2
Show that the equations x^2-7x+6=0 and y^2-14y+40=0 form a rectangle.Also find the joint equations of diagonals.
Answer:
1) The region between the four lines x = 6, x = 1, y = 4 and y = 10 describing both equations is a rectangle
2) The joint equations of diagonals are;
5·y = 56 - 6·x and 5·y = 6·x + 14.
Step-by-step explanation:
The equations are;
x² - 7·x + 6 = 0......................(1)
y² - 14·y + 40 = 0.................(2)
Factorizing equation (1) and equation (2) , we get
x² - 7·x + 6 = (x - 6)·(x - 1) = 0
Which are vertical lines at points x = 6 and x = 1
For equation (2) , we get
y² - 14·y + 40 = (y - 10)·(y - 4) = 0
Which are horizontal lines at point y = 4 and y = 10
The region between the four lines x = 6, x = 1, y = 4 and y = 10 describing both equations is a rectangle
2) The points of intersection of the equations are;
(1, 4), (1, 10), (6, 4), and (6, 10)
The end point of the diagonals are;
(1, 10), (6, 4) and (1, 4), (6, 10)
The slope of the diagonals are;
(10 - 4)/(1 - 6) = -6/5 and (4 - 10)/(1 - 6) = 6/5
The equation of one of the diagonals are then, y - 10 = -6/5×(x - 1)
y = -6/5·x + 6/5 + 10 = -6/5·x + 56/5
5·y = 56 - 6·x
The other diagonal is therefore;
y - 4 = 6/5×(x - 1)
y = 6/5·x - 6/5 + 4 = 6/5·x + 14/5
5·y = 6·x + 14.
The joint equations of diagonals are therefore;
5·y = 56 - 6·x and 5·y = 6·x + 14.
5
What is the equation, in point-slope form, of the line that
is parallel to the given line and passes through the point
(-3, 1)?
4
3
2
(-3, 1)
42.27
1
5 4 3 2 1
2 3 4 5 x
y-1=-{(x+3)
y-1=-{(x + 3)
y-1= {(x + 3)
y-1= {(x + 3)
(-2, 4)
Answer: [tex]y-1=\dfrac32(x+3)[/tex]
Step-by-step explanation:
Slope of a line passes through (a,b) and (c,d) = [tex]\dfrac{d-b}{c-a}[/tex]
In graph(below) given line is passing through (-2,-4) and (2,2) .
Slope of the given line passing through (-2,-4) and (2,2) =[tex]\dfrac{-4-2}{-2-2}=\dfrac{-6}{-4}=\dfrac{3}{2}[/tex]
Since parallel lines have equal slope . That means slope of the required line would be .
Equation of a line passing through (a,b) and has slope m is given by :_
(y-b)=m(x-a)
Then, Equation of a line passing through(-3, 1) and has slope = is given by
[tex](y-1)=\dfrac32(x-(-3))\\\\\Rightarrow\ y-1=\dfrac32(x+3)[/tex]
Required equation: [tex]y-1=\dfrac32(x+3)[/tex]
Ramona works in a clothing store where she earns a base salary of $140 per day plus 14% of her daily sales. She sold $600 in clothing on Saturday and $1200 in clothing on Sunday. How much did she earn over the two days? A. $252 B. $291 C. $392 D. $532
Answer:
I hope this helps!
Answer D
Step-by-step explanation:
Step-by-step explanation:
salary per day =$140
bonus on sales =14%
sales on Saturday =$600
bonus on Saturday sales=14/100*$600
=$84
sales on Sunday =$1200
bonus on Sunday sales=14/100*$1200
=$168
total amount she earned over the two days=$140+$84+$168
=$532
Please answer. I need this to be done, Thanks. Will give brainliest
Answer:
The answer is s^26/pq59
Step-by-step explanation:
Answer:
p^ -1 q ^ -59 s ^26
or without negative exponents
s^ 26 /(p q^ 59)
Step-by-step explanation:
When multiplying , we can add the exponents when the bases are the same
p^0 q ^ -60 r^-1 s^25 * p^-1 qrs
When there is no exponent written, there is an implied 1
p^ (0+-1) q^(-60+1) r ^( -1 +1) s ^ ( 25+1)
p^ -1 q ^ -59 r ^0 s ^26
r^0 = 1
p^ -1 q ^ -59 s ^26
If you need the negative exponents written as positive
a^-b = 1/ a^b
s^ 26 /(p q^ 59)
what is the coefficient of the variable in the expression 4-3x
As per the question,
We have to find what's the coefficient.
Let's start to seperate the expression.
Here,
x is the variable,
4 is a number.
-3 is also a number.
4, -3x
The number with x here is -3 in (-3x) as the coefficient is (-3) in the given equation.
Answer:
Hey there!
Rearrange the expression to: -3x+4
The coefficient would be -3.
Let me know if this helps :)
How to do this question plz answer me step by step plzz plz plz plz plz plz plz plz
Answer:
288.4m
Step-by-step explanation:
This track is split into a rectangle and two semi-circles.
We can find the length of the semi-circles by finding its circumference with the formula [tex]2\pi r[/tex].
[tex]2\cdot3.14\cdot30\\188.4[/tex]
However this is half a circle, so:
[tex]188.4\div2=94.2[/tex].
There are two semi-circles.
[tex]94.2\cdot2=188.4[/tex]
Since there are two legs of 50m each, we add 100 to 188.4
[tex]188.4+100=288.4[/tex]m
Hope this helped!
Answer:
Step-by-step explanation:
To solve for the perimeter, we first look at the rectangle in the middle. the length is 50m, and there are two sides to it, so: 50 * 2 = 100m for the top and bottom of the track.
For the circle, we can see the diameter is 30m. To solve for the circumference, we need to use the formula 2πr.
15 * 2π ≈ 94.2477796077
We add that to 100m and get:
194.2477796077
Find the amplitude of y = -2 sin x
Answer:
Amplitude = 2
Step-by-step explanation:
The amplitude of this sine wave is 2 denoted by the coefficient -2 in front of the sin(x). The negative of the coefficient denotes that the sine wave is the opposite of the standard sine wave.
Cheers.
Which graph solves the following system? x+2y=4 5x−2y=8
Answer:
elimination method
x+2y=4 1
5x-2y=8 2
1+2
6x=12
x=2
plug into x+2y=4
2+2y=4
2y=4-2
2y=2
y=1
(2,1)
so graph 1
what is the value of this expression when g= -3.5?
8-|2g-5|
a. 20
b. 10
c. 6
d. -4
Answer:
d. -4
Step-by-step explanation:
Let's plug in g
8 - |2(-3.5) - 5|
8 - |-7-5|
8 - |-12|
The absolute value is always positive of any number,
8 - 12
= -4
Answer:
D. -4
Step-by-step explanation:
We are given this expression:
[tex]8-|2g-5|[/tex]
and asked to evaluate when g= -3.5 Therefore, we must substitute -3.5 in for g.
[tex]8-|2(-3.5)-5|[/tex]
First, multiply 2 and -3.5
2 * -3.5 = -7
[tex]8-|-7-5|[/tex]
Next, subtract 5 from -7.
-7-5= -12
[tex]8-|-12|[/tex]
Next, evaluate the absolute value of -12. The absolute value is how far away a number is from 0, and it is always positive. The absolute value of -12 is 12.
[tex]8-12[/tex]
Subtract 12 from 8.
[tex]-4[/tex]
The value of the expression is -4 and D is the correct answer.
HELP ASAP
[tex]Given that $33^{-1} \equiv 77 \pmod{508}$, find $11^{-1} \pmod{508}$ as a residue modulo 508. (Give an answer between 0 and 507, inclusive.)[/tex]
===================================================
Work Shown:
[tex]33^{-1} \equiv 77 \text{ (mod 508)}\\\\(3*11)^{-1} \equiv 77 \text{ (mod 508)}\\\\3^{-1}*11^{-1} \equiv 77 \text{ (mod 508)}\\\\3*3^{-1}*11^{-1} \equiv 3*77 \text{ (mod 508)}\\\\11^{-1} \equiv 231 \text{ (mod 508)}\\\\[/tex]
Notice how 33*77 = 2541 and 11*231 = 2541
[tex]2541 \equiv 1 \text{ (mod 508)}[/tex] since 2541/508 has a remainder of 1.
So effectively [tex]33*77 \equiv 1 \text{ (mod 508)}[/tex] and [tex]11*231 \equiv 1 \text{ (mod 508)}[/tex]
Please answer this question now
Answer:
11 yd
Step-by-step explanation:
To find the volume of a rectangular prism, we multiply the width, length and height.
We already know the length, 18, and the height, 11, and the volume, 2178, so we can easily solve for y.
[tex]18\cdot y\cdot11=2178\\192y=2178\\y = 11[/tex]
Hope this helped!
This table represents a quadratic function.
y
x
0
14
1
10.5
2
8
3
6.5
4
5
6.5
What is the value of a in the function's equation?
A.2
B.1/2
C.-1/2
D.1
Answer:
B. 1/2
Step-by-step explanation:
y = ax^2 + bx + c
14 = a(0)^2 + b(0) + c
c = 14
10.5 = a(1)^2 + b(1) + 14
10.5 = a + b + 14 ____(i)
8 = a(2)^2 + b(2) + 14
8 = 4a + 2b + 14
4 = 2a + b + 7 ___ (ii)
i - ii
10.5 - 4 = -a + 7
6.5 = -a + 7
a = 7- 6.5
a = 0.5
Value of a in the quadratic function is 0.5
What is Quadratic function?In algebra, a quadratic function, a quadratic polynomial, a polynomial of degree 2, or simply a quadratic, is a polynomial function with one or more variables in which the highest-degree term is of the second degree
Given,
Quadratic function
y = [tex]ax^{2}+bx+c[/tex]
Consider values in the table x= 0 and y =14
[tex]14=a(0)^{2}+b(0)+c\\ c=14[/tex]
Consider x=1 and y = 10.5
[tex]10.5=a(1^{2})+b(1)+c\\ a+b=10.5-14\\a+b=-3.5[/tex]
Consider x=2 and y =8
[tex]8=a(2^{2})+b(2)+c\\ a\\8=4a+2b+14\\4a+2b=-6\\2a+b=-3[/tex]
Subtract a + b= -3.5 from 2a + b= -3
a=-3--3.5=0.5
Hence, the Value of a in the quadratic function is 0.5
Learn more about Quadratic function here
https://brainly.com/question/5975436
#SPJ2
Which statement correctly compares
1–201 and
1512
ol-201 = 151
ol-201 < 51
l-201 > 151
Answer:
Option B.
Step-by-step explanation:
Consider the correct question is "Which statement correctly compares
1. -201 and 151
-201 = 151
-201 < 51
-201 > 151"
The given numbers are -201 and 151. We need to compare these numbers.
We know that all negative numbers are less than positive numbers.
So,
-201 < 151
If both numbers are negative, then the larger negative number is the smaller number.
Therefore, the correct option is B.
Please answer this question now
Answer:
298.3 square centimeters
Step-by-step explanation:
We are given
Slant height (l)= 14cm
Radius (r)= 5cm
Since we are given the slant height ,
the formula for surface area of a cone =
πrl + πr²
πr(l + r)
π = 3.14
Hence,
3.14 × 5(14 + 5)
3.14 × 5(19)
= 298.3 square centimeters
Question 1 (
Multiple Choice Worth 3 points)
(07.04)
The cost of 3 slices of pizza is $4.89. What is the cost of each slice of pizza?
O $1.63
$1.89
O $2.45
O $2.88
Answer:
Each slice of pizza cost:
$1.63
Step-by-step explanation:
4.89/3 = 1.63
Answer:
$1.63
Step-by-step explanation:
We want to find the cost per slice of pizza. Therefore, we must divide the total cost by the number of slices of pizza.
cost / slices
It costs $4.89 for 3 slices.
$4.89 / 3 slices
Divide 4.89 by 3 (4.89/3=1.63)
$1.63 / slice
The cost of each slice of pizza is $1.63
Help with this find the image of (1 ,2) after a reflection about y=x followed by a reflection about y=-x
Answer: (-1, -2)
Step-by-step explanation:
so at first you have (1, 2)
then you were asked to reflect about y=x which is (x, y) = (y, -x)
(1, 2) = (2, -1)
then followed by y=-x which is (x, y) = (-y, -x)
(2, -1) = (-1, -2)
I hope this helps!
Company a samples 16 workers, and their average time with the company is 5.2 years with a standard deviation of 1.1. Company b samples 21 workers and their average time with the company is 4.6 years with a standard deviation 4.6 years
Company a samples 16 workers, and their average time with the company is 5.2 years with a standard deviation of 1.1. Company b samples 21 workers and their average time with the company is 4.6 years with a standard deviation 4.6 years
The populations are normally distributed. Determine the:
Hypothesis in symbolic form?
Determine the value of the test statistic?
Find the critical value or value?
determine if you should reject null hypothesis or fail to reject?
write a conclusion addressing the original claim?
Answer:
Step-by-step explanation:
GIven that :
Company A
Sample size n₁ = 16 workers
Mean [tex]\mu[/tex]₁ = 5.2
Standard deviation [tex]\sigma[/tex]₁ = 1.1
Company B
Sample size n₂ = 21 workers
Mean [tex]\mu[/tex]₂ = 4.6
Standard deviation [tex]\mu[/tex]₂ = 4.6
The null hypothesis and the alternative hypothesis can be computed as follows:
[tex]H_o : \mu _1 = \mu_2[/tex]
[tex]H_1 : \mu _1 > \mu_2[/tex]
The value of the test statistics can be determined by using the formula:
[tex]t = \dfrac{\overline {x_1}- \overline {x_2}}{\sqrt{\sigma p^2( \dfrac{1}{n_1}+\dfrac{1}{n_2})}}[/tex]
where;
[tex]\sigma p^2= \dfrac{(n_1 -1) \sigma_1^2+ (n_2-1)\sigma_2^2}{n_1+n_2-2}[/tex]
[tex]\sigma p^2= \dfrac{(16 -1) (1.1)^2+ (21-1)4.6^2}{16+21-2}[/tex]
[tex]\sigma p^2= \dfrac{(15) (1.21)+ (20)21.16}{35}[/tex]
[tex]\sigma p^2= \dfrac{18.15+ 423.2}{35}[/tex]
[tex]\sigma p^2= \dfrac{441.35}{35}[/tex]
[tex]\sigma p^2= 12.61[/tex]
Recall:
[tex]t = \dfrac{\overline {x_1}- \overline {x_2}}{\sqrt{\sigma p^2( \dfrac{1}{n_1}+\dfrac{1}{n_2})}}[/tex]
[tex]t = \dfrac{5.2- 4.6}{\sqrt{12.61( \dfrac{1}{16}+\dfrac{1}{21})}}[/tex]
[tex]t = \dfrac{0.6}{\sqrt{12.61( \dfrac{37}{336})}}[/tex]
[tex]t = \dfrac{0.6}{\sqrt{12.61(0.110119)}}[/tex]
[tex]t = \dfrac{0.6}{\sqrt{1.38860059}}[/tex]
[tex]t = \dfrac{0.6}{1.178388981}[/tex]
t = 0.50917
degree of freedom df = ( n₁ + n₂ - 2 )
degree of freedom df = (16 + 21 - 2)
degree of freedom df = 35
Using Level of significance ∝ = 0.05, From t-calculator , given that t = 0.50917 and degree of freedom df = 35
p - value = 0.3069
The critical value [tex]t_{\alpha ,d.f}[/tex] = [tex]t_{0.05 , 35}[/tex] = 1.6895
Decision Rule: Reject the null hypothesis if the test statistics is greater than the critical value.
Conclusion: We do not reject the null hypothesis because, the test statistics is lesser than the critical value, therefore we conclude that there is no sufficient information that the claim that company a retains it workers longer than more than company b.
Suppose the population of a country is 100 people: 40 work full-time, 20 work half-time but would prefer to work full-time, 10 are looking for a job, 10 would like to work but are so discouraged they have given up looking, 10 are not interested in working because they are full-time students, and 10 are retired. What is the number of unemployed
Answer:
10
Step-by-step explanation:
Those people who are actively seeking for a job are counted as unemployed. Underemployment is not considered as unemployment. Those who have given up looking for jobs are also not considered as unemployed as well. Hence there are 10 unemployed people.
every rational number is a
a. whole number b. natural number c. integer d. real number
Greetings from Brasil...
a - whole number
FALSE
3/5, for example isnt a whole number
b. natural number
FALSE
0,457888..., for example isnt a natural number
c. integer
FALSE - like a
d. real number
TRUE
The set of real numbers contains the set of rational numbers
ℝ ⊃ ℚ
The diagonal of rhombus measure 16 cm and 30 cm. Find it's perimeter
Answer:
P = 68 cmStep-by-step explanation:
The diagonals of the rhombus divide it into 4 congruent right triangles.
So we can use Pythagorean theorem to calculate side of a rhombus.
[tex](\frac e2)^2+(\frac f2)^2=s^2\\\\e=30\,cm\quad\implies\quad\frac e2=15\,cm\\\\f=16\,cm\quad\implies\quad\frac f2=8\,cm\\\\15^2+8^2=s^2\\\\s^2=225+64\\\\s^2=289\\\\s=17[/tex]
Perimeter:
P = 4s = 4•17 = 68 cm
41 =12d-7 d= Math is not my strong suit. I love to read and write but I can not do math without a little bit of help.
Answer:
[tex]\huge\boxed{d = 4 }[/tex]
Step-by-step explanation:
41 = 12d - 7
Adding 7 to both sides
41+7 = 12d
48 = 12 d
Dividing both sides by 12
4 = d
OR
d = 4
Answer:
[tex]\large \boxed{{d=4}}[/tex]
Step-by-step explanation:
[tex]41 =12d-7[/tex]
Add 7 on both sides.
[tex]41 +7=12d-7+7[/tex]
[tex]48=12d[/tex]
Divide both sides by 12.
[tex]\displaystyle \frac{48}{12} =\frac{12d}{12}[/tex]
[tex]4=d[/tex]
Solve for h. 3/7=h/14-2/7
Answer:
h = 10
Step-by-step explanation:
Given
[tex]\frac{3}{7}[/tex] = [tex]\frac{h}{14}[/tex] - [tex]\frac{2}{7}[/tex]
Multiply through by 14 to clear the fractions
6 = h - 4 ( add 4 to both sides )
10 = h
Answer:
10
Step-by-step explanation:
We start out with 3/7 = h/14 - 2/7
add 2/7 to both sides:
(5/7) = h/14
Multiply both sides by 14 to get rid of the fraction:
h = 10
the product of 5 and z
Answer:
5z
Step-by-step explanation:
As product = multiplication =>
5 x z --> 5(z)
[tex]\text{Find the product of 5 and z}\\\\\text{The key term in this questions is product, and in math it translates to}\\\text{the answer when multiplled}\\\\\text{In this case, you would multiply them together to get your "product"}\\\\\text{Solve:}\\\\5\cdot z\\\\\boxed{5z}[/tex]
A bag contains 2
2
blue marbles, 2
2
red marbles, and 2
2
yellow marbles.
If Jenna randomly draws a marble from the bag (and puts it back) 15
15
times, how many times should she expect to pull a yellow marble?
Answer:
5 times
Step-by-step explanation:
Jenna wil most likely pull a yellow marble 1/3 of the time, because the total number of marbles is 6, and there are 2 yellow marbles, 2/6 which is 1/3. 1/3 times 15 is 5. So Jenna will most likely pull a yellow marble 5 times.
PLEASE HELP ASAP!!
The image above shows two dilated figures with lines IJ and JK drawn. If the smaller figure was dilated by a scale factor of 2, what relationship do lines IJ and KL have?
Answer:
[tex] IJ = 2(KL) [/tex]
Step-by-step explanation:
From the information given, the smaller figure was dilated on a scale factor of 2, to produce the bigger figure. In essence, the bigger figure is times 2 of the smaller figure.
Therefore, line IJ would be twice the length of KL.
The relationship that both lines have can be represented as: [tex] IJ = 2(KL) [/tex]
I NEED HELP PLEASE I GIVE 5 STARS !
Answer:
C. 2[tex]\sqrt{29}[/tex]
Step-by-step explanation:
Square root of 116 is 10.7703296
Square root of 29 is 5.38516481, but as it is multiplied by 2, it becomes 10.7703296
Consider the function represented by 9x + 3y = 12 with x as the independent variable. How can this function be
written using function notation?
O FID = - Šv
O f(x) = - 3x + 4
Of(x) = -x +
O fly) = -34+4
Answer:
f(x) = - 3x + 4
Step-by-step explanation:
Note that y = f(x)
Rearrange making y the subject
9x + 3y = 12 ( subtract 9x from both sides )
3y = - 9x + 12 ( divide all terms by 3 )
y = - 3x + 4 , that is
f(x) = - 3x + 4
please help me i offered all my points and this is really important!!! The question is attached.
Answer:
25[tex]\sqrt{3}[/tex] +60
Step-by-step explanation: The first thing you need to do is realize that, this figure is a isosceles trapezoid due to the markings on each side.
So now we know both sides are 10.
We also know the the top two angles are congruent to each other and so are the bottom two angles due to the trapezoid being isosceles.
So the top two angles are 120 degrees and bottom two angles are 60 degrees.
It seems like we can't find the sides, let's try drawing two lines from each top angle all the way down to form two right triangles.
Wow, these two triangles are special right triangles in the form of
30 - 60 - 90 degrees.
shorter side = n
longer side = n[tex]\sqrt{3}[/tex]
hypotenuse = 2n
So, 2n = 10
n = 5 for the short side
The bottom base is 4[tex]\sqrt{3}[/tex] + 5 + 5 = 10 + 4[tex]\sqrt{3}[/tex]
The longer side is 5[tex]\sqrt{3}[/tex].
The area of trapezoid = (base1 + base2)/2 * height
= (4[tex]\sqrt{3}[/tex] + 10 + 4[tex]\sqrt{3}[/tex])/2 * 5[tex]\sqrt{3}[/tex] = (10 + 8[tex]\sqrt{3}[/tex])/2 * 5[tex]\sqrt{3}[/tex] = (5+4[tex]\sqrt{3}[/tex])*5[tex]\sqrt{3}[/tex] = 25[tex]\sqrt{3}[/tex] +60
So, 25[tex]\sqrt{3}[/tex] + 60 is our answer.
Answer:
60 +25√3
Step-by-step explanation:
In the figure of the isosceles trapezoid below, the angles at C and D are supplementary to the given angle, so are 60°. That makes triangle BDE a 30°-60°-90° right triangle, which has side length ratios ...
DE : BE : BD = 1 : √3 : 2 = 5 : 5√3 : 10
Triangle BDE can be relocated to the other end of the figure to become triangle CAD'. Then the area of concern is that of the rectangle with height 5√3 and length 5+4√3. The area is then ...
Area = lh = (5√3)(5 +4√3) = 5·5√3 +5·4·3
Area = 60 +25√3 . . . square units
_____
In the figure, 6.93 = 4√3, and 8.66 = 5√3, 16.93 = 10+4√3.
Write and solve an equation to answer the question. How many people must attend the third show so that the average attendance per show is 3000?
Answer:
3250
Step-by-step explanation:
so for the first and 2nd show, the attendance is 2580 and 2920.
The average of both these numbers is 2750
the if the third show had 3000 people, the average attendance would only be 2875.
We need the average number to be 3000.
2750 is 250 less than 3000, so the other number must be 250 more.
3250 is how many people should go to the last show.
=====================================
Explanation:
We have 2580 people attend the first show and 2920 attend the second. So far, that's 2580+2920 = 5500 people. Add on another x people to get 5500+x, which represents the sum of all three days attendance figures. Divide this sum by 3 to get the average attendance
average attendance = (sum of individual attendance values)/(number of days)
average attendance = (5500+x)/3
So that's why (5500+x)/3 goes in the first box. The parenthesis are important to ensure that you divide all of "5500+x" over 3. If you just wrote 5500+x/3, then the computer would think you just want to divide x only over 3.
----------------
We set (5500+x)/3 equal to 3000 as we want the average of the three days to be 3000
(5500+x)/3 = 3000
5500+x = 3*3000
5500+x = 9000
x = 9000-5500
x = 3500
We need 3500 people to show up on day 3 so that the average of all three days is 3000.
3500 goes in the second box.
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Check:
The figures for the three days are 2580, 2920, and 3500
They add to 2580+2920+3500 = 9000
Which divides to 9000/3 = 3000, which is the average we're after. So the answer is confirmed.