Answer:
600 is the missing space
Step-by-step explanation:
rate me brainliest plz
A number “x” increased by 5 is 19?
Answer:
x+5=19
Step-by-step explanation:
i think that right let me know...:/
Answer:
x= 14
Step-by-step explanation:
a number x increased by 5, so it will be x + 5 and is in math means equals to so it becomes
x+5=19
19-5=x
14=x
88 feet/second = 60 miles/hour. How many feet per second is 1 mile/hour? (Hintdivide both sides of the equation
by the same amount.)
Round to the nearest thousandth.
One mile per hour is equivalent to
ao feet/second.
Answer:
1 miles/hour = 1.467·feet/second
Step-by-step explanation:
The given measurement unit are;
88 feet/second = 60 miles/hour
The number of feet per second that is equal to one mile per hour is found as follows;
88 feet/second = 60 miles/hour
To have a unit measure of one mile per hour , we divide both sides of the equation by 60 to get
(88 feet/second)/60 = (60 miles/hour)/60
Which gives;
(88/60 feet/second) = (60/60 miles/hour) = 1 miles/hour
22/15 × feet/second = 1 miles/hour
1.46667·feet/second = 1 miles/hour
Rounding to the nearest thousandth gives;
1.467·feet/second = 1 miles/hour
The number of feet per second that is in 1 mile per hour is 1.467·feet/second.
Deshaun bought 6 bags of sugar for his restaurant. Each bag weighed 6.9 kilograms. How many kilograms of sugar did he buy total?
Answer:
41.4 kgs
Step-by-step explanation:
Take the number of bags times the weight of each bag
6 * 6.9
41.4 kgs
Answer:
41.4 kilograms of sugar
Step-by-step explanation:
its 41.4 kilograms of sugar because you take the 6 bags and multiply that by the 6.9
Add or subtract. Write your answer in scientific notation.
4.2 x 10^6 − 1.2 x 10^5 − 2.5 x 10^5
3.3 x 10^9 + 2.6 x 10^9 + 7.7 x 10^8
8.0 x 10^4 − 3.4 x 10^4 − 1.2 x 10^3
Answer:
1. 38.3 x 10^5
2. 6.67 x 10^9
3. 4.48 x 10^4
Step-by-step explanation:
4.2 X 10 ^6 - 1.2 X 10^5 - 2.5 x 10^5
For the above question, we need to make the exponents equal
=> 42 x 10^5 - 1.2 x 10^5 - 2.5 x 10^5
SInce, all the exponents are equal, we can now add and subtract the normally.
=> (42 - 1.2 -2.5) x 10^5
=> (42 - 3.7) x 10^5
=> 38.3 x 10^5
So, the answer to the 1st question is 38.3 x 10^5
Next question:
=> 3.3 x 10^9 + 2.6 x 10^9 +7.7 x 10^8
=> we need to make the exponents equal
=> 3.3 x 10^9 + 2.6 x 10^9 + .77 x 10^9
=> All the exponents are equal, we can now add and subtract the normally.
=> (3.3 + 2.6 + .77) x 10^9
=> 6.67 x 10^9
=> So the answer to the 2nd question is 6.67 x 10^9
Next question,
=> 8 X 10^4 - 3.4 x 10^4 - 1.2 x 10^3
=> we need to make the exponents equal
=> 8 x 10^4 - 3.4 x 10^4 - .12 x 10^4
=> All the exponents are equal, we can now add and subtract the normally.
=> (8 - 3.4 - .12) x 10^4
=> 4.48 x 10^4
=> So the answer to the 3rd question is 4.48 x 10^4
The solutions to the expressions are:
[tex]4.2 \times 10^6 - 1.2 \times 10^5 - 2.5 \times 10^5[/tex]=[tex]38.3\times 10^5[/tex]
[tex]3.3 \times 10^9 + 2.6 \times 10^9 + 7.7 \times 10^8[/tex] = [tex]6.67\times 10^9[/tex]
[tex]8.0 \times 10^4 -3.4 \times 10^4 - 1.2 \times 10^3[/tex] = [tex]4.48 \times 10^4[/tex]
[tex]4.2 \times 10^6 - 1.2 \times 10^5 - 2.5 \times 10^5[/tex]
Combine like terms:
[tex]4.2 \times 10^6 - (1.2+2.5) \times 10^5[/tex]
[tex]4.2 \times 10^6 - 3.7 \times 10^5[/tex]
[tex]42 \times 10^5 - 3.7 \times 10^5[/tex]
[tex](42-3.7)\times 10^5[/tex]
[tex]38.3\times 10^5[/tex]
[tex]3.3 \times 10^9 + 2.6 \times 10^9 + 7.7 \times 10^8[/tex]
Convert all terms with same power:
[tex]3.3 \times 10^9 + 2.6 \times 10^9 + 0.77 \times 10^9[/tex]
[tex](3.3+2.6+0.77) \times 10^9[/tex]
[tex]6.67\times 10^9[/tex]
[tex]8.0 \times 10^4 -3.4 \times 10^4 - 1.2 \times 10^3[/tex]
[tex]8.0 \times 10^4 - 3.4 \times 10^4 - 0.12 \times 10^4[/tex]
[tex](8.0-3.4-0.12) \times 10^4[/tex]
[tex]4.48 \times 10^4[/tex]
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This composite figure is made of two identical pyramids attached at their bases. Each pyramid has a height of 2 units. 2 identical pyramids with rectangular bases are connected at their base. The height of the pyramid is 2. The lengths of the sides of the rectangle are 5 and 0.25 units. Which expression represents the volume, in cubic units, of the composite figure? One-half (One-third (5) (0.25) (2) ) One-half (One-third (5) (0.25) (4) ) 2(One-third (5) (0.25) (2) ) 2(One-third (5) (0.25) (4) )
Answer:
The total volume of the solid is 1.67 cubic units.
Step-by-step explanation:
Each pyramid with a height of 2 units and a rectangular base with dimensions of 5 units × 0.25 units.
1/3 x (area of base) x height
= 1/3 x (5 x 0.25) x 2= 0.833
Therefore, the volume of each pyramid will be
= cubic units.
So, the total volume of the solid is (2 × 0.833) = 1.67 cubic units. (Answer)
Hope it helped ya!
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Tysmm
The total volume of the solid is 1.67 unit³.
What is Volume?Each thing in three dimensions takes up some space. The volume of this area is what is being measured. The space occupied within an object's borders in three dimensions is referred to as its volume. It is sometimes referred to as the object's capacity.
Given:
Each pyramid has a height of 2 units.
and the rectangular base with dimensions of 5 units × 0.25 units.
So, the Volume of each Pyramid is
= 1/3 x (area of base) x height
= 1/3 x (5 x 0.25) x 2
= 0.833
and, the total volume of the solid
= (2 × 0.833)
= 1.67 cubic units.
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find the area of a sector with a central angle of 150 and a diameter of 7.8 cm
Answer:
19.9 cm²
Step-by-step explanation:
The following data were obtained from the question:
Angle at the centre (θ) = 150°
Diameter (d) = 7.8 cm
Area of sector =.?
Next, we shall determine the radius.
This can be obtained as illustrated below:
Radius (r) = Diameter (d) /2
r = d/2
Diameter (d) = 7.8 cm
Radius (r) =.?
r = d/2
r = 7.8/2
r = 3.9 cm
Finally, we shall determine the area of the sector as follow:
Angle at the centre (θ) = 150°
Radius (r) = 3.9 cm
Pi (π) = 3.14
Area of sector (A) =.?
A = θ/360 × πr²
A = 150/360 × 3.14 × 3.9²
A = 15/36 × 3.14 × 15.21
A = 19.9 cm²
Therefore, the area of the sector is 19.9 cm²
The company will be launching a firework from the ground, but you want to increase the time it stays in the air by 2 seconds to build up the suspense. How can the company make this happen without changing the length of the fuse? How will this affect the maximum height of the firework? g(t) = -16t2 + 224t + 120
Answer: find the answer in the explanation.
Step-by-step explanation:
To increase the time the fireworks stays in the air by 2 seconds to build up the suspense, 2 should be added to the time t.
T + 2 = t
T = t - 2
Substitute T for t in the function g(t)
The company will make this happen without changing the length of the fuse by substituting T for t which will lead to
g(t) = -16(t - 2)^2 + 224(t - 2) + 120
How will this affect the maximum height of the firework?
Initially the function is:
g(t) = -16t2 + 224t + 120
Where the time at maximum height is found by using the formula
t = -b/2a
b = 224, a = -16
Substitutes both into the formula
t = -224/2(-16)
t = -224/-32
t = 7
Substitute 7 for t in the first equation
g(t) = -16(7)^2 + 224(7) + 120
g(t) = -16(49) + 224(7) + 120
g(t) = -784 + 1568 + 120
g(t) = 904 metres
But when the time is delayed by 2 seconds in the air, the maximum height will be
g(t) = -16( 7 - 2 )^2 + 224(7 - 2) + 120
g(t) = -16(5)^5 + 224(5) + 120
g(t) = -16(25) + 224(5) + 120
g(t) = -400 + 1120 + 120
g(t) = 840
The effect will surely reduce the maximum height of the fireworks.
2. Marci bought 6 shirts at Old Navy. Her subtotal
(before tax) was $73.50. If each shirt was the same
price, how much did each shirt cost?
Answer:
12.25
Step-by-step explanation:
73.50 divided by 6 for each shirt is 12.25 a shirt
inscribed angles. help asap!
Answer:
20°
Step-by-step explanation:
The measure of the inscribed angle is equal to the half of the arc it sees
Since AC is the diameter the measure of arc ABC is 180°
and since A sees arc BC and C sees the arc AB
A< + C< = 90° so angle C = 20°
what are the squares from one to twenty
Answer:
1,4,9,16
Step-by-step explanation:
those are the squares
1 = 1²
4 = 2²
9 = 3²
16 = 4²
Step-by-step explanation:
[tex] {1}^{2} = 1 \times 1 = 1 \\ {2}^{2} = 2 \times 2 = 4 \\ {3}^{2} = 3 \times 3 = 9 \\ {4}^{2} = 4 \times 4 = 16 \\[/tex]
[tex] {5}^{2} = 5 \times 5 = 25 \\ [/tex]
[tex] {10}^{2} = 10 \times 10 = 100[/tex]
[tex] {6}^{2} = 6 \times 6 = 36 \\ {7}^{2} = 7 \times 7 = 49 \\ {8}^{2} = 8 \times 8 = 64 \\ {9}^{2} = 9 \times 9 = 81 \\ [/tex]
[tex] {11}^{2} = 11 \times 11 = 121 \\ {12}^{2} = 12 \times 12 = 144 \\ {13}^{2} = 13 \times 13 = 169 \\ {14}^{2} = 14 \times 14 = 196 \\ [/tex]
[tex] {15}^{2} = 15 \times 15 = 225 \\ {16}^{2} = 16 \times 16 = 256 \\ {17}^{2} = 17\times 17 = 289 \\ {18}^{2} = 18 \times 18 = 324[/tex]
[tex] {19}^{2} = 19 \times 19 = 361 \\ {20}^{2} = 20 \times 20 = 400[/tex]
Find all values of $x$ such that \[\frac{2x}{x + 2} = -\frac{6}{x + 4}.\]If you find more than one value, then list your solutions, separated by commas.
Greetings from Brasil...
2X/(X + 2) = 6/(X + 4)
2X(X + 4) = 6(X + 2)
2X² + 2X - 12 = 0 ÷2
2X²/2 + 2X/2 - 12/2 = 0/2
X² + X - 6 = 0Δ = 25
X' = 2X'' = - 3S = {-3, 2}
By using factorization, [tex]\frac{2x}{x+2} =\frac{6}{x+4}[/tex] , values of x are -2, 3.
What is factorization?Factorization can be defined as the process of breaking down a number into smaller numbers which when multiplied together arrive at the original number. These numbers are broken down into factors or divisors.
Given
[tex]\frac{2x}{x+2} =\frac{6}{x+4}[/tex]
⇒ 2x(x + 4) = 6(x + 2)
⇒ [tex]2x^{2} +8x = 6x + 12[/tex]
⇒ [tex]2x^{2} +8x-6x-12=0[/tex]
⇒ [tex]2x^{2} +2x -12=0[/tex]
Divide above equation by 2, we get
⇒ [tex]x^{2} +x -6=0[/tex]
⇒ [tex]x^{2} +2x-3x-6=0[/tex]
⇒ [tex]x(x+2)-3(x+2)=0[/tex]
⇒ [tex](x+2)(x-3)=0[/tex]
⇒ x = -2, 3
By using factorization, [tex]\frac{2x}{x+2} =\frac{6}{x+4}[/tex] , values of x are -2, 3.
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what are the roots of the quadratic equation below 2x^2+8x+7=0
Answer:
x = -1.29 and -2.71
Step-by-step explanation:
Use the quadratic formula, which is [tex]x=\frac{-b+\sqrt{b^2-4ac} }{2a}[/tex] and [tex]x=\frac{-b-\sqrt{b^2-4ac} }{2a}[/tex]
[tex]\frac{-8+\sqrt{8^2-4(2)(7)} }{2(2)}[/tex] and [tex]\frac{-8-\sqrt{8^2-4(2)(7)} }{2(2)}[/tex]
[tex]\frac{-8+\sqrt{8} }{4}[/tex] and [tex]\frac{-8-\sqrt{8} }{4}[/tex]
Further reduced down to:
[tex]\frac{-8+2\sqrt{2} }{4}[/tex] and [tex]\frac{-8-2\sqrt{2} }{4}[/tex]
In decimal form, to the hundredths place, both of these are:
-1.29 and -2.71
Can someone answer this please? Okay so it says that something is made 3 times than the other item. The other item uses 13 beads. So, what is 13 times 3?
Answer:
13x3= 39
Step-by-step explanation:
10x3=30
3x3=9
30+9=39
Hope it helps!
The tens digit of a two-digit number is three times greater than the ones digit. The difference between twice the original number and half the number obtained after reversing the digits is 108. What is the original number? Show your work.
Answer:
Now solve these two equations.ull get andwer
The original number will be "63".
Let,
The ten's digit be "x".One's digit be "y".The equation will be:
→ [tex]x=y+3[/tex]...(equation 1)
Original number will be:
→ [tex]10x+y[/tex]
then,
→ [tex]2 (10x+y)-\frac{(10y+x)}{2} = 108[/tex]
→ [tex]\frac{4(10x+y)}{1} -(10y+x) = 216[/tex]
→ [tex]40x+4y-10y-x = 216[/tex]
→ [tex]39x-6y=216[/tex]...(equation 2)
By using (equation 1) and (equation 2), we get
→ [tex]39(y+3)-6y=216[/tex]
→ [tex]39y+117-6y=216[/tex]
→ [tex]33y=99[/tex]
→ [tex]y = \frac{99}{33}[/tex]
→ [tex]= 3[/tex]
Now,
[tex]x = y+3[/tex]
[tex]=3+3[/tex]
[tex]=6[/tex]
hence,
The original number will be:
= [tex]10x+y[/tex]
= [tex]10\times 6+3[/tex]
= [tex]60+3[/tex]
= [tex]63[/tex]
Thus the above approach is right.
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Can someone please help? the answer is 5/12 but I have no idea how. Please explain the steps!
Answer:
5/12
Step-by-step explanation:
4√y√y / 3√y
The above equation can be simplified as follow:
4√y√y / 3√y
4√y × √y ÷ 3√y
Recall:
√a = a^1/2
m√a = a^1/m
Therefore,
4√y√y ÷ 3√y
y^1/4 × y^1/2 ÷ y^1/3
Recall:
a^m × a^n = a^(m+n)
Therefore,
y^1/4 × y^1/2 ÷ y^1/3
y^(1/4 + 1/2) ÷ y^1/3
y^3/4 ÷ y^1/3
Recall:
a^m ÷ a^n = a^(m–n)
Therefore,
y^3/4 ÷ y^1/3
y^(3/4 – 1/3)
y^5/12
Comparing the above with y^m, we have
y^5/12 = y^m
m = 5/12
Therefore, the value of m is 5/12
Need help please asap this is not asap but please still give an answer im stuck
Answer:
135 cubes
Step-by-step explanation:
First, find the volume of the box with the equation V = Bh, where B is the area of the base and h is the height.
V = (2.25)(0.75)(1.25)
V = 2.109375
Next, find the volume of one cube with the side length 1/4 with V = Bh:
V = (0.25)(0.25)(0.25)
V = 0.015625
Then, divide the volume of the box by the volume of one cube:
2.109375 / 0.015625
= 135
find the roots of the following equation X + 1 whole square minus x square equal to 2
Answer:
x = 1/2
Step-by-step explanation:
Let's represent this in a mathematical way,
(x+1)^2 - x^2 = 2
Ok now we expand,
x^2 + 2x + 1 -x^2 = 2
rearrange,
x^2 - x^2 + 2x + 1 = 2
subtract,
2x + 1 = 2
subtract 1 from both sides,
2x + 1 - 1 = 2 - 1
2x = 1
Now divide 2 from both sides and get your answer,
x = 1/2
Answer:
[tex](x + 1) { }^{2} - x {}^{2} = 2[/tex]
[tex]x {}^{2} + 2x + 1 - x {}^{2} = 2[/tex]
[tex]2x + 1 = 2[/tex]
[tex]x = 1 \div 2[/tex]
PLEASE help me with this question! No nonsense answers please. This is really urgent.
Answer:
The third option: x= [tex]\frac{8}{3} \pi[/tex]
Step-by-step explanation:
Arc length formula=[tex]\frac{Central Angle}{360} * 2\pi r[/tex]
Arc length = [tex]\frac{120}{360} *2\pi (4)[/tex]
=[tex]\frac{8}{3}\pi[/tex]
consider the polynomial 8x^3+2x^2-20x-5 factor
Answer:
(4x + 1)(2x² - 5)
Step-by-step explanation:
Given
8x³ + 2x² - 20x - 5 ( factor the first/second and third/fourth terms )
= 2x²(4x + 1) - 5(4x + 1) ← factor out (4x + 1) from each term
= (4x + 1)(2x² - 5)
Answer:
blank 1 is -20-5
blank 2 is 4x+1
blank 3 is -5
blank 4 is 2x^2-5
Step-by-step explanation:
can you make a triangle with 1. 2cm 3cm and 4cm 2. 2cm 3 cm 6 cm 3. 90 degrees 45 degrees 45 degrees 4. 90 degrees 60 degrees 60 degrees?
Answer:
1. 2cm 3cm and 4cm
yes, because 2+3>4
2. 2cm 3 cm 6 cm
no, 2+3<6
3. 90 degrees 45 degrees 45 degrees
yes, 90+45+45 = 180
4. 90 degrees 60 degrees 60 degrees?
no, 90+60+60=210!=180
Combine your expressions from part E (x+2) and part F (y+ (-4) to give the pair of coordinates of any point after a translation two yards East and four yards south.
Answer:
A'(5, 2), B'(5, -1), C'(6, -1), D'(6, 2)
Step-by-step explanation:
A transformation is the movement of a point from its initial position to a final position. If an object is transformed all its points are also transformed. Types of transformation are reflection, rotation, translation and dilation.
If a point O(x, y) is translated left by h unit, the new coordinate is O'(x-h, y) while if O(x, y) is translated right by h unit the new coordinate is O'(x+h, y)
If a point O(x, y) is translated up by h unit, the new coordinate is O'(x, y+h) while if O(x, y) is translated down by h unit the new coordinate is O'(x, y-h)
The location of the shape as shown in the diagram is:
A(3, 6), B(3, 3), C(4, 3), D(4, 6)
If the points are translated two yards East and four yards south, it means it is translated 2 unit right and 4 unit down i.e. (x+2, y-4). The new coordinates are:
A'(5, 2), B'(5, -1), C'(6, -1), D'(6, 2)
Answer:
ombining the expressions from parts E and F, for any given initial point (x, y), the coordinates of the new point after a translation of two yards east and four yards south are (x + 2, y + (-4)).
Step-by-step explanation:
this is more simple
need help will give you a good rating us
Answer:
[tex]\boxed{2\pm \frac{\sqrt{2}}{2}}[/tex]
Step-by-step explanation:
[tex]2x^2-8x=-7[/tex]
[tex]\sf Add \ 7 \ on \ both \ sides}.[/tex]
[tex]2x^2-8x+7=-7+7[/tex]
[tex]2x^2-8x+7=0[/tex]
[tex]ax^2 +bx+c=0[/tex]
[tex]\sf Apply \ quadratic \ formula.[/tex]
[tex]a=2 \ \ \ b=-8 \ \ \ c = 7[/tex]
[tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
[tex]x=\frac{-(-8)\pm\sqrt{(-8)^2-4(2)(7)}}{2(2)}[/tex]
[tex]x=\frac{8\pm\sqrt{64-56}}{4}[/tex]
[tex]x=\frac{8\pm\sqrt{8}}{4}[/tex]
[tex]x=\frac{8\pm2\sqrt{2}}{4}[/tex]
[tex]x=2\pm \frac{\sqrt{2}}{2}[/tex]
Plz ans ASAP! Tysm! Pzlllzzz!
Answer:
Step-by-step explanation:
Number of class intervals = 7
Class width = 5
Class intervals (heights) Frequency (Number of boys)
130 - 135 3
136 - 140 5
141 - 145 3
146 - 150 5
151 - 155 2
156 - 160 1
161 - 165 1
Therefore, frequency table given above will represent the distribution of the heights and number of students.
What is the perimeter of a square with side length (2x-3)?
Answer:
Perimeter = 8x - 12
Step-by-step explanation:
The perimeter of a square is:
p = 4(side length)
on this case:
p = 4(2x-3)
p = 4*2x + 4*-3
p = 8x - 12
Please help ASAP. The question is down below.
Answer:
2.7 hours
Step-by-step explanation:
We can use the formula
1/a + 1/b = 1/c
where a and b are the times working alone and c is the time working together
1/8 + 1/b = 1/2
Multiply each side by 8b to get rid of the fractions
8b( 1/8 + 1/b = 1/2)
b + 8 = 4b
Subtract b from each side
b+8-b = 4b-b
8 = 3b
Divide each side by 3
8/3 = 3b/3
2.666666repeating = b
Round to 1 decimal place
2.7 = b
Answer:
2.7 hr
Step-by-step explanation:
2/8 +2/x = 1
2x+16 =8
16/8
x=8/3 =2.7
PLEASE HELP!!!!
The degree of x y 3 + 5 x 2 y − 3 x xy 3 +5x 2 y−3xis 8. True False
Answer:
it's true
Step-by-step explanation:
Two trains station at the same time one travels east at 8 miles per hour .The other train traveles east at 8 millas per hour the other train travels west at 11 miles per hour in how many hours will the two trains apart
what are the order of operations for integers ?
Answer:
PEMDAS
Step-by-step explanation:
P - Parentheses (Brackets also!)
E - Exponents
M and D - Multiplication and division. Many people think multiplication has to be done first as said in "PEMDAS" but it doesn't. Do multiplication and division according to which ever one is farthest to the left (left to right).
A and S - Addition and subtraction. Same thing applies here, neither addition or subtraction has to be done first, just do them according to which one is farthest to the left when reading the expression from left to right.
6r-1+6r=11 explain how to get so
Answer:
r = 1
Step-by-step explanation:
6r - 1 + 6r = 11
Adding 6r and 6r (because they're like terms) gives us:
12r - 1 = 11
Adding 1 to both sides of the equation gives us:
12r - 1 + 1 = 11 + 1
12r = 12
Dividing both sides of the equation by 12 gives us:
12r/12 = 12/12
r = 1
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.
----------------
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.