Answer:
[tex]Radius = 1.997\ in[/tex] and [tex]Height = 7.987\ in[/tex]
[tex]Cost = \$1.05[/tex]
Step-by-step explanation:
Given
[tex]Volume = 100in^3[/tex]
[tex]Cost =\$0.014[/tex] -- Top and Bottom
[tex]Cost =\$0.007[/tex] --- Sides
Required
What dimension of the cylinder minimizes the cost
The volume (V) of a cylinder is:
[tex]V = \pi r^2h[/tex]
Substitute 100 for V
[tex]100 = \pi r^2h[/tex]
Make h the subject
[tex]h = \frac{100 }{\pi r^2}[/tex]
The surface area (A) of a cylinder is:
[tex]A = 2\pi r^2 + 2\pi rh[/tex]
Where
[tex]Top\ and\ bottom = 2\pi r^2[/tex]
[tex]Sides = 2\pi rh[/tex]
So, the cost of the surface area is:
[tex]C = 2\pi r^2 * 0.014+ 2\pi rh * 0.007[/tex]
[tex]C = 2\pi r(r * 0.014+ h * 0.007)[/tex]
[tex]C = 2\pi r(0.014r+ 0.007h)[/tex]
Substitute [tex]h = \frac{100 }{\pi r^2}[/tex]
[tex]C = 2\pi r(0.014r+ 0.007*\frac{100 }{\pi r^2})[/tex]
[tex]C = 2\pi r(0.014r+ \frac{0.007*100 }{\pi r^2})[/tex]
[tex]C = 2\pi r(0.014r+ \frac{0.7}{\pi r^2})[/tex]
[tex]C = 2\pi (0.014r^2+ \frac{0.7}{\pi r})[/tex]
Open bracket
[tex]C = 2\pi *0.014r^2+ 2\pi *\frac{0.7}{\pi r}[/tex]
[tex]C = 0.028\pi *r^2+ \frac{2\pi *0.7}{\pi r}[/tex]
[tex]C = 0.028\pi *r^2+ \frac{2 *0.7}{r}[/tex]
[tex]C = 0.028\pi *r^2+ \frac{1.4}{r}[/tex]
[tex]C = 0.028\pi r^2+ \frac{1.4}{r}[/tex]
To minimize, we differentiate C w.r.t r and set the result to 0
[tex]C' = 0.056\pi r - \frac{1.4}{r^2}[/tex]
Set to 0
[tex]0 = 0.056\pi r - \frac{1.4}{r^2}[/tex]
Collect Like Terms
[tex]0.056\pi r = \frac{1.4}{r^2}[/tex]
Cross Multiply
[tex]0.056\pi r *r^2= 1.4[/tex]
[tex]0.056\pi r^3= 1.4[/tex]
Make [tex]r^3[/tex] the subject
[tex]r^3= \frac{1.4}{0.056\pi }[/tex]
[tex]r^3= \frac{1.4}{0.056 * 3.14}[/tex]
[tex]r^3= \frac{1.4}{0.17584}[/tex]
[tex]r^3= 7.96178343949[/tex]
Take cube roots of both sides
[tex]r= \sqrt[3]{7.96178343949}[/tex]
[tex]r= 1.997[/tex]
Recall that:
[tex]h = \frac{100 }{\pi r^2}[/tex]
[tex]h = \frac{100 }{3.14 * 1.997^2}[/tex]
[tex]h = \frac{100 }{12.52}[/tex]
[tex]h = 7.987[/tex]
Hence, the dimensions that minimizes the cost are:
[tex]Radius = 1.997\ in[/tex] and [tex]Height = 7.987\ in[/tex]
To calculate the cost, we have:
[tex]C = 2\pi r(0.014r+ 0.007h)[/tex]
[tex]C = 2* 3.14 * 1.997 * (0.014*1.997+ 0.007*7.987)[/tex]
[tex]Cost = \$1.05[/tex]
The cylinder has a surface area of 972cm. Find x. Round to the nearest whole number.
diameter: 2x
height: 5x
Answer:
A= 2pirh +2pir^2
972=2 x pi x x x 5x + 2 x pi x x^2
972= 31.4x^2 + 6.28x^2
972=37.68x^2
x^2= 972/37.68
x^2=25.796
x= 25.796 square root
x= 5
The value of x is 5 cm.
What is a cylinder?A cylinder is a three-dimensional figure that has a radius and a height.
The volume of a cylinder is given as
Example:
The volume of a cup with a height of 5 cm and a radius of 2 cm is
Volume = 3.14 x 2 x 2 x 5 = 62.8 cubic cm
We have,
The surface area of a cylinder = 972 cm²
The surface area of a cylinder.
= 2πrh + 2πr²
Diameter = 2x
Radius = x
Height = 5x
Now,
2πrh + 2πr² = 972
2π (rh + r²) = 972
2π (5x² + x²) = 972
2π x 6x² = 972
6x² = 972/(2 x 3.14)
6x² = 154.78
x² = 25.79
x = √25.79
x = 5.08
x = 5
Thus,
x value is 5.
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help plz will give brainlyest
Answer:
A. Cendric is correct because he used the inverse of subtraction and added 4.5
Step-by-step explanation:
To solve for x, all we needed to do was to make x stand alone. To do this, we have to apply addition property of equality. This means we would add 4.5 to both sides for the equation to balance. Thus, we would have z standing alone which equals 3.
Therefore, Cendric was correct because he used the inverse of subtraction of -4.5, which is 4.5 that was later added to both sides of the equation.
Which statements are true regarding the two figures ? Select three options.
The order of rotational symmetry for the seven- pointed star is 7
The order of rotational symmetry for the five-pointed star is 3
The smallest angle of rotational symmetry for the seven - pointed star rounded to the nearest tenth is 51.4
The smallest angle of rotational symmetry for the five pointed star is 72 degrees
The five-pointed star has a smaller angle of rotational symmetry than the seven-pointed star .
Answer:
im pretty sure 1 and 5 are correct i dont know the 3rd one though
Step-by-step explanation:
Answer:
c
Step-by-step explanation:
I really need help on this question
Answer:
[tex]r = 107 \\ q + s = 180 - 107 \\ = 73 \\ q = 73 \div 2 \\ = 36.5[/tex]
If mQOS = 46, and mPOR = 61
and mPOQ = 28, what is mROS?
Answer:
ROS = 225°
Step-by-step explanation:
The four corners of the squares add up to 360°
Hope it helps you
Angles at a point add up to [tex]360^o[/tex]. The measure of [tex]m\angle ROS[/tex] is [tex]225^o[/tex]
Given that:
[tex]m\angle QOS = 46^o[/tex]
[tex]m\angle POR = 61^o[/tex]
[tex]m\angle POQ = 28^o[/tex]
The 4 angles (i.e. QOS, POR, POQ and ROS) are all angles at a point (i.e. point O).
This means that we can apply the angle at a point theorem.
The theorem is represented as:
[tex]m\angle QOS +m\angle POR +m\angle POQ + m\angle ROS = 360^o[/tex] --- i.e. angles at a point add up to [tex]360^o[/tex]
So, we have:
[tex]46^o + 61^o + 28^o + m\angle ROS = 360^o[/tex]
[tex]135^o + m\angle ROS = 360^o[/tex]
Collect like terms
[tex]m\angle ROS = 360^o -135^o[/tex]
[tex]m\angle ROS = 225^o[/tex]
Hence, the measure of [tex]m\angle ROS[/tex] is [tex]225^o[/tex]
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9. Which of the following relations is a function?
A. {(-1, - 4), (-1,0), (- 1,5), (- 1, 7), (- 1,9)}
B. {(-2, - 4), (-1, 7), (1, - 1), (1, 1), (3, 9)}
C. {(-4, 9), (- 3, 1), (- 2, 3), (- 2, 12), (0, 6)
D. {(0, - 4), (1, - 4), (2, 4), (3, 4), (4, - 4)}
The relation which is a function is given by the set relation
A = { ( 0 , 4 ) , ( 1 , -4 ) , ( 2 , 4 ) , ( 3 , 4 ) , ( 4 , -4 ) }
What is a function rule?The function rule is the relationship between the input or domain and the output or range. A relation is a function if and only if there exists one value in the range for every domain value.
A function is a relation from a set of inputs to a set of possible outputs where each input is related to exactly one output.
Given data ,
Let the function be represented as A
Now , the value of A is
Let the values of x be x = { 0 , 1 , 2 , 3 , 4 }
Now , the values of y = { 4 , -4 , 4 , 4 , -4 }
And , relation is a function if and only if there exists one value in the range for every domain value.
So , the domain are all having significant and definite ranges
Therefore , the relation is A = { ( 0 , 4 ) , ( 1 , -4 ) , ( 2 , 4 ) , ( 3 , 4 ) , ( 4 , -4 ) }
Hence , the function is denoted by A = { ( 0 , 4 ) , ( 1 , -4 ) , ( 2 , 4 ) , ( 3 , 4 ) , ( 4 , -4 ) }
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Pls help will give brainlest to first person who answer correct 50 points
Answer:
-25/3
Step-by-step explanation:
Please let me know if you want me to add an explanation as to why this is the answer/how I got this answer. I can definitely do that, I just wouldn’t want to write it if you don’t want me to :)
Answer:
x = - 25/3Step-by-step explanation:
10/3 = x/(-5/2)x = 10/3*(-5/2)x = - 25/34(x+4) + 2x = 52 need answer
Answer:
x=6
Step-by-step explanation:
9-3 divided by 1/3 + 1
Answer:
1
Step-by-step explanation:
Is the expression 3(x+1 1/2)-3 equivalent to 3x+ 1 1/2
Answer:
Yes
Step-by-step explanation:
3(x+5.50)-3
3x+16.50)-3
-3(3x+16.50)
Please help I’ll mark you as brainliest if correct
Answer:
72 cm³ (see below)
Step-by-step explanation:
First, refer to the volume formula:
V = l · w · h
If you plug in all of your values and simplify, you'll get the volume:
l = 6 cm
w = 3 cm
h = 4 cm
V = (6) (3) (4)
V = 18 (4)
V = 72 cm³
Because this is volume, the measurements are units cubed, meaning it's cm³.
will mark brainlyist
Answer:
x=18.7
Step-by-step explanation:
x+17+5x+10+4x-34=180
10x-7=180
10x=187
x=18.7
all angles in a trianlge add up to 180 degrees
Answer:
x = 17
Step-by-step explanation:
Since all angles of a triangle equal to 180 we can make this equation:
x + 17 + 6x + 10 + 4x - 34 = 180
11x - 7 = 180
11x = 187
x = 17
Please help!! Will make brainliest
UmmmmAnswer:
Step-by-step explanation:
(Click the Picture for my question) and thank you!
Answer:
D
Step-by-step explanation:
By definition, π is defined to be the ratio of a circle's circumference to its diameter. In other words:
[tex]\displaystyle \pi=\frac{C}{d}[/tex]
In fact, if you multiply both sides by the diameter d, you can see that:
[tex]C=\pi d[/tex]
Which is the formula for circumference you've been commonly taught.
3/5 of the students in a classroom are girls. If there are ten boys in the class, how many total students are there?
15
25
16
20
Answer:
25
Step-by-step explanation:
15=Girls
10=Boys
25 =The total of the number of students
y = 5. – 7 2y = –12 -3x
Answer:
!! solved as -7(2y)= -12(-3x)
x= negative 1.943333
Step-by-step explanation:
10 MINUTES UNTIL I HAVE TO TURN TEST IN
HELP PLS :)
Answer:
10) Total Discount = $15 dollars; New Amount = $60 dollars.
11) Total Markup = $3,750 dollars; New Amount = $28,750 dollars.
12a) Percent Increase from $100 to $150: 50% increase.
12b) Percent Decrease from $150 to $100: 33.33% decrease.
Step-by-step explanation:
I would be more than happy to show my work, but I see that you have to submit your test soon, so I will just leave it at this for now. If you need any clarification, I am more than happy to help. Feel free to give me Brainliest if you feel this helped! Have a good day, and good luck on your test. :)
Which fraction is equal to 35%?
O A.
100
350
O B.
100
35
C.
3.5
100
D.
35
100
Answer: D 35/100
Step-by-step explanation: if you divide 35/100, the answer would be .35, which is the decimal form of 35%.
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What is the value of x in the proportion?
Answer:
Step-by-step explanation:
Cross multiply on both sides
= (x + 1) (21) = 15(x + 3)
= 21x + 21 = 15x + 45
Bringing like terms on one side
21x - 15x = 45 - 21
= 6x = 24
x = 24/6 = 4
Option A is the correct answer
[tex] =\tt (a) \: 4[/tex]
Steps to derive correct option :[tex] = \frac{x + 1}{x + 3} = \frac{15}{21} [/tex]
[tex] =( x + 1 )\times 21 = (x + 3 )\times 15[/tex]
[tex] = 21x + 21 = 15x + 45[/tex]
[tex] = 21x + 21 - 15x = 45[/tex]
[tex] = 6x + 21 = 45[/tex]
[tex] = 6x = 45 - 21[/tex]
[tex] = 6x = 24[/tex]
[tex] = x = \frac{24}{6} [/tex]
[tex] =\color{plum} \bold{x = 4}[/tex]
Let us now place 4 in the place of x and see if the substitution is equivalent to [tex] \frac{15}{21} [/tex] :
[tex] = \frac{4 + 1}{4 + 3} = \frac{15}{21} [/tex]
[tex] = \frac{5}{7} = \frac{15}{21} [/tex]
[tex] = \frac{5}{7} = \frac{15÷3}{21÷3} [/tex]
[tex] = \frac{5}{7} = \frac{5}{7} [/tex]
Therefore, the value of x in this proportion = 4
Which relation is a function?
{(1, −1), (−2, 2), (−1, 2), (1, −2)}
{(1, 2), (2, 3), (3, 2), (2, 1)}
{(1, 4), (2, 3), (3, 2), (4, 1)}
{(4, 2), (3, 3), (2, 4), (3, 2)}
Answer:
c
Step-by-step explanation:
because all the x values in c are different
What’s the function and domain and range. (1, -2) (-2, 0) (-1, 2) (1, 3)
Answer: Domain:
{
1
,
−
2
,
−
1
}
{
1
,
-
2
,
-
1
}
Range:
{
−
2
,
0
,
2
,
3
}
Step-by-step explanation: The domain is the set of all the values of
x
x
. The range is the set of all the values of
y
y
.
Pls help I’m failing math I’ll brainlest
Answer:
z=-9 - 5.4
hope it helps
Step-by-step explanation:
please mark me brainliest
Tori earned $62.86 as a bonus from her job. She decided to buy as many CDs as possible since they were on sale for $8.80 each. Estimate how many CDs Tori can buy.
Answer:
approximately 7 CDs for her bonus
Answer:
Toris can buy about 7 CDs
Step-by-step explanation:
63 Divided by 9 = 7
Type of triangle the has side measures of 6cm, 7cm and 12cm. And one angle with a measure of 120 degrees
Answer:
Obtuse triangle
Step-by-step explanation:
Given
Sides: 6cm, 7cm and 12cm
Angle: 120 degree
Required
Determine the type of triangle
Because the measure of an angle of the triangle was mentioned, we have to classify the triangle by its angle.
From the question, we understand that one of the angles is greater than 90 (i.e. 120 degrees). This type of triangle are referred to as obtuse triangles.
6(2x - 5) = -(x + 4)
[tex]6(2x - 5) = - (x + 4)[/tex]
[tex]12x - 30 = - x - 4[/tex]
[tex]13x = 26[/tex]
[tex]x = 2[/tex]
Answer:
x = 2
Step-by-step explanation:
Solve for x:
6(2x - 5) = -(x + 4)
Use the distributive property.
12x - 30 = -(x + 4)
12x - 30 = -x - 4
Add x to both sides.
13x - 30 = -4
Add 30 to both sides.
13x = 26
Divide both sides by x.
x = 2
Your final answer would be x = 2
What is the perimeter of the figure?
Answer:
138cm
Step-by-step explanation:
there are 2 sides equal to 27
27 + 27 = 54
there are 6 squares = to 14
6 × 14 = 84
54 + 84 = 138
Gabe Amodeo, a nuclear physicist, needs 90 liters of a 50% acid solution. He currently has a 30% solution and a 60% solution. How many liters of each does he need to make the needed 90 liters of 50% acid solution?
Answer:
You need two equations: one for solution amounts and one for alcohol amounts.
Step-by-step explanation:
90 = X + Y
45 = (0.6)/X + (0.3)Y
Here X = amount of 60 % solution and Y = amount of 30 percent solution. Note that percentages have been converted to decimal amounts in the second equation.
From here you have to solve two equations with two unknowns. Easiest to solve first equation for X = 90 - Y, then substitute into second equation. this get you one equation in one unknown. Solving you you will get
X = 30 liters and Y = 60 liters.
Proportionally means
2 fractions (ratios) are NOT equal
2 fractions (ratios) are equal
Answer:
2 fractions are equal
Step-by-step explanation:
We say that two quantities are proportional if one is always the same multiple of the other.
Say a recipe calls for 2 cups of flour to 3 eggs. That proportion, 2 cups flour : 3 eggs, will always stay the same, no matter how many serving we make. If we make 2 servings, we'd double to 4 cups and 6 eggs, but that wouldn't change the proportion. After all,
[tex]\frac{2}{3}=\frac{4}{6}[/tex]
5d
P= 15 +
12
what is d
Answer:
Step-by-step explanation:
10
What number is 120% of 16?
Answer:19.2
Step-by-step explanation:
