Answer:
please answer only neeed solve questions
Step-by-step explanation:
I think hlp
Answer: No question asked.
Step-by-step explanation:
If you are making a problem, please actually ask a question. It will use your points if you make questions that don't really mean anything. Thank you.
The pie chart is best because pie charts are a good way to portray percentage based data. B. The Pareto chart is best because it allows you to see which sources account for most of the electricity. C. The pie chart is best because pie charts should always be used when comparing percentages. D. The Pareto chart is best because the bars make it easy to visually compare the different percentages. E. Neither type of chart is a good way to portray the data.
Answer:
The pie chart is best because pie charts are a good way to portray percentage based data.
Step-by-step explanation:
Pie charts are used for graphical representation of data. The data can be shown in percentages or numbers. It is easy for the user to understand the data in the pie chart because it clearly represents the data in circular graphical form.
Segment EG is an angle bisector of angle FGH. Noah wrote a proof to show that triangle HEG is congruent to triangle FEG. Noah's proof is not correct. Which line of Noah's proof is incorrect, and why1. Side EG is congruent to side EG because they're the same segment.
2. Angle EGH is congruent to angle EGF because segment EG is an angle bisector of angle FGH.
3. Angle HEG is congruent to angle FEG because segment EG is an angle bisector of angle FGH.
4. By the Angle-Side-Angle Triangle Congruence Theorem, triangle HEG is congruent to triangle FEG.
Line 2 is incorrect; there is not enough information given to state this.
Line 2 is incorrect; there is not enough information given to state this.
Line 2 is incorrect; even though segment EG is a bisector, angles EGH and FGH are not necessarily congruent.
Line 2 is incorrect; even though segment , EG, is a bisector, angles , EGH, and , FGH , are not necessarily congruent.
Line 3 is incorrect; we don't know anything about the lengths of HG, FG, HE, and EF, so this line is not valid based on the given information.
Line 3 is incorrect; we don't know anything about the lengths of , HG, , , FG, , , HE, , and , EF, , so this line is not valid based on the given information.
Line 4 is incorrect; Angle-Side-Angle is not a valid congruence theorem.
Line 4 is incorrect; Angle-Side-Angle is not a valid congruence theorem.
Answer:
Line 3 is incorrect; we don't know anything about the lengths of HG, FG, HE, and EF, so this line is not valid based on the given information.
Step-by-step explanation:
In the Noah's poof of the construction, segment EG would divide angle FGH into two equal parts, which makes line 2 to be valid. i.e <EGH ≅ <EGF. And it can also be observed that line 4 is a valid theorem in proving the congruent nature of triangles.
But line 3 is not valid because of the condition of the statement. Furthermore, segments FG, EG, HG, HE and FE may not be congruent. Thus, the condition of the statement in line 3 is incorrect.
Chris was given 1/3 of the 84 cookies in the cookie jar. He ate 3/4 of the cookies that he was given. How many cookies did Chris eat?
Answer:
21 cookies
Step-by-step explanation:
First we know that Chris was given a third of 84 cookies so we can start working on this problem by figuring out what a third of 84 is. We can do this by multiplying 84 by 1/3 or just dividing by 3, which gives us: 84/3 = 28
So now we know that Chris was given 28 cookies, we can figure out what 3/4 of that is to work out how many cookies he ate. 28 x (3/4) = 21 cookies.
Chris ate 21 cookies.
Hope this helped!
Answer:
21 cookies
Step-by-step explanation:
1/3 × 84 = 28
3/4 × 28 = 21
Find the value of unknown figure plz tell i will mark as brainliest
Answer:
1. [tex]2^{3}[/tex] x [tex]3^{6}[/tex]
ii. 18
b. -12
2. nth = a + (n - 1)d
ii. k = 103
3. [tex]x^{o}[/tex] = [tex]27^{o}[/tex]
4. Volume = 25.025 [tex]m^{3}[/tex]
Step-by-step explanation:
1. Prime factors of 5832 = 2 x 2 x 2 x 3 x 3 x 3 x 3 x 3 x 3
= [tex]2^{3}[/tex] x [tex]3^{6}[/tex]
ii. [tex]\sqrt[3]{5832}[/tex] = 18
b. 2[tex]a^{2}[/tex] - 3[tex]b^{2}[/tex] + 3abc
a = 3, b = 2, c = -1
Thus,
2[tex](3)^{2}[/tex] - 3[tex](2)^{2}[/tex] + 3(3 x 2 x -1)
= 18 - 12 - 18
= -12
2. The required formula is;
nth = a + (n - 1)d
where: a is the first term, n is the number of terms in the sequence and d is the common difference.
b. kth term = 304, then
304 = -2 + (k - 1) 3
= -2 + 3k -3
= 3k - 5
3k = 304 + 5
3k = 309
k = [tex]\frac{309}{3}[/tex]
= 103
k = 103
3. Comparing <DAB and < EBC;
<DAB ≅ <EBC = [tex]x^{o}[/tex]
<BEC = [tex]90^{o}[/tex] (right angle property)
<C = [tex]63^{o}[/tex]
Thus,
<B + <C + <E = [tex]180^{o}[/tex] (sum of angles in a triangle)
[tex]x^{o}[/tex] + [tex]63^{o}[/tex] + [tex]90^{o}[/tex] = [tex]180^{o}[/tex]
[tex]x^{o}[/tex] + 153 = [tex]180^{o}[/tex]
[tex]x^{o}[/tex] = 180 - 153
= 27
[tex]x^{o}[/tex] = [tex]27^{o}[/tex]
4. Volume of a cylinder = [tex]\pi[/tex][tex]r^{2}[/tex]h
where r is the radius and h is the height of the cylinder.
Diameter = 3.5 m, h = 2.6 m
r = [tex]\frac{3.5}{2}[/tex]
r = [tex]\frac{7}{4}[/tex] m
So that,
Volume = [tex]\frac{22}{7}[/tex] x [tex](\frac{7}{4}) ^{2}[/tex] x 2.6
= [tex]\frac{22}{7}[/tex] x [tex]\frac{49}{16}[/tex] x [tex]\frac{13}{5}[/tex]
= 25[tex]\frac{1}{40}[/tex]
Volume = 25.025 [tex]m^{3}[/tex]
can someone help me please?! I'll give brainlest for correct answer
1.) The answers:
A) BME
B) MER
C) Mm
D) xBy
E) Straight
F) REB
G) MEB and BER
H) xBy
Adam bought three kinds of
bagels at the bagel store. He
bought twice as many onion bagels as plain
bagels. He bought four more sesame
bagels than he did plain bagels. Adam ate
one of the sixteen onion bagels he bought
as soon as he got home. How many bagels
does Adam have left?
9514 1404 393
Answer:
35
Step-by-step explanation:
The 16 onion bagels are twice as many as plain bagels, so there were 8 plain bagels.
There were 4 more sesame bagels than plain bagels, so there were 12 sesame bagels.
Adam has 8 plain, 12 sesame, and 15 onion bagels left, for a total of 35 bagels left.
Ms.Peralta's friend Mike is a construction worker. Mike gets paid $15 an hour. After working 9 hours he gets paid 1.25 times his hourly rate. Below you can find Mike's hours for last Friday. - Mike worked for 5 hours - took an 1 hr and 15 minute break for lunch (does not count toward his work hours) - worked for an additional 7.5 hours How much money did Mike make last Friday?
Answer:
Mike made $ 200.63 last Friday.
Step-by-step explanation:
Since Ms. Peralta's friend Mike is a construction worker who gets paid $ 15 an hour, and after working 9 hours he gets paid 1.25 times his hourly rate, and last Friday Mike worked for 5 hours - took an 1 hr and 15 minute break for lunch (does not count toward his work hours) - and worked for an additional 7.5 hours, to determine how much money did Mike make last Friday the following calculation must be performed:
5 + 7.5 = 12.5
12.5 - 9 = 3.5
9 x 15 + (3.5 x (15 x 1.25)) = X
135 + 3.5 x 18.75 = X
135 + 65.625 = X
200.63 = X
Therefore, Mike made $ 200.63 last Friday.
CAN SOMEONE HELP ME WITH THIS?!
Answer:
a = 14
b = 24
c = 24.9
A = 33.2 degrees
B = 70 degrees
C = 76.8 degrees
Step-by-step explanation:
a/sin(A) = b/sin(B) = c/sin(C)
14/sin(A) = 24/sin(70)
sin(A)×24 = sin(70)×14
sin(A) = sin(70)× 14/24 = sin(70) × 7/12 = 0.548154029...
A = asin(0.548154029...) = 33.240464... degrees
the sum of all angles in a triangle is airways 180 degrees.
C = 180 - 70 - 33.240464... = 76.75954... degrees
24/sin(70) = c/sin(76.75954...)
c = 24×sin(76.75954...)/sin(70) = 24.86133969...
Which system of inequalities does the graph represent?
Answer:system of linear equalities in one variable .
Step-by-step explanation:
Multiply the following using the vertical multiplication method: 3x^2-5x+1
x x^2+2x+4
9514 1404 393
Answer:
3x^4 +x^3 +3x^2 -18x +4
Step-by-step explanation:
The multiplication is done the same way as "long multiplication" with numbers. Each partial product is placed in the column corresponding to its "place value" (the degree of the variable). The only difference from numerical multiplication is that the sums of the partial products have no carry into any column with a different "place value".
use the diagram below to find all missing angles
Answer:
Step-by-step explanation:
Soooo, angle 1 is 157 degrees
That means:
Angle 2 is 23 degrees Supplementary Angles
Angle 3 is 157 degrees Vertical Angle to Angle 1
Angle 4 is 23 degrees Vertical angle to Angle 2
Answers:
angle 2 = 23 degreesangle 3 = 157 degreesangle 4 = 23 degrees=======================================================
Explanation:
Angles 1 and 2 are supplementary as they form a straight line. So the angles add to 180
(angle1)+(angle2) = 180
angle2 = 180-(angle1)
angle2 = 180-157
angle2 = 23 degrees
Angle 4 is congruent to this because angles 2 and 4 are vertical angles. Vertical angles are always congruent. Note how angles 1 and 4 are supplementary.
Since angles 1 and 3 are the other pair of vertical angles, this must mean angle 3 is 157 degrees.
Only answer if you're very good at math.Please I keep on posting this but nobody is helping me.
What is the 4th term of the expansion of (1 - 2x)^n if the binomial coefficients are taken from the row of Pascal's triangle shown below?
1 6 15 20 15 6 1
A: 240x^4
B: 160x^3
C: -160x^3
D: -20x^3
The fourth term of the given expansion is [tex]-280x^{3}[/tex].
What is binomial expansion?
The binomial expansion is used to expand and write the terms which are equals to the natural number exponent of the sum or differences of two terms.
The general term of the binomial expansion is given by[tex]T_{r+1} =nC_{r} x^{n-r} y^{r}[/tex]
According to the given question
We have,
A binomial expression, [tex](1-2x)^{n}[/tex]
and, the binomial coefficients are taken from the row of Pascal's triangle 1 6 15 20 15 6 1
⇒ n = 7
Therefore,
The fourth term of the expansion of [tex](1-2x)^{n}[/tex] is given by
[tex]T_{3+1} = 7C_{3} 1^{7-3} (-2x)^{3}[/tex]
[tex]T_{4} =\frac{(7)(6)(5)(4)(3!)}{3!(4)(3)(2)} (1)(-2x)^{3}[/tex]
[tex]T{4} = -280x^{3}[/tex]
Hence, the fourth term of the given expansion [tex](1-2x)^{3}[/tex] is [tex]-280x^{3}[/tex].
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Is this correct? I just started learning negative numbers.
Answer:
It's on the negative side, so make sure you put -2.25. But yes, it's right.
Find the circumference of the circle.
Help please, solve and explain
Answer:
Step-by-step explanation:
17.
18.
f(x)=6x^2+7x-4
(a)
f(3)=6(3)^2+7(3)-4
=54+21-4
=71
(b)
f(m)=6m^2+7m-4
(c)
f(x+1)=6(x+1)²+7(x+1)-4
=6(x²+2x+1)+7x+7-4
=12x²+12x+6+7x+7-4
=12x²+19x+9
19.
(fg)(x)=f(g(x)=f(2x²+3)=2x²+3+5=2x²+8
20.
(a)
f(x)=x²+3x+4
domain:all real values
(b)
domain:all real values≥-2
(c)f(x)=log(x+7)
Domain:x≥-7
21.
x²+6x+y²-7=0
(x²+6x+6/2)²)-(6/2)²+y²=7
(x+3)²+y²=7+9
(x+3)²+y²=4²
center=(-3,0)
radius=4
22.
(x-3)²+(y-5)²=3²
or
x²-6x+9+y²-10y+25=9
x²+y²-6x-10y+25=0
Graph is for 17th question.
Classify the triangle shown below.
ضع تصنيفا للمثلث الموضح أدناه.
11 cm
3 cm
13 cm
Answer:
Scuse me what the flip
Suppose you have entered 115-mile biathlon that consists of a run and a bicycle race. During your run, your average velocity is 9 miles per hour, and during your bicycle race, your average velocity is 22 miles per hour. You finish the race in 7 hours. What is the distance of the run? What is the distance of the bicycle race?
Answer:
The distance of the run was 27 miles and the distance of the bicycle race was 88 miles.
Step-by-step explanation:
Since I have entered 115-mile biathlon that consists of a run and a bicycle race, and during my run, my average velocity is 9 miles per hour, and during my bicycle race, my average velocity is 22 miles per hour , and I finish the race in 7 hours, to determine what is the distance of the run and what is the distance of the bicycle race, the following calculations must be performed:
7 x 22 + 0 x 9 = 154
5 x 22 + 2 x 9 = 128
4 x 22 + 3 x 9 = 115
Therefore, the distance of the run was 27 miles and the distance of the bicycle race was 88 miles.
400 is 100 times as much as
Which expression is equivalent to x(97-12)?
– 12
Answer:
85x−12
Step-by-step explanation:
Write the equation of the trigonometric graph.
Answer(s):
[tex]\displaystyle y = 3sin\: (1\frac{1}{2}x + \frac{\pi}{2}) - 2 \\ y = 3cos\: 1\frac{1}{2}x - 2[/tex]
Explanation:
[tex]\displaystyle y = Asin(Bx - C) + D \\ \\ Vertical\:Shift \hookrightarrow D \\ Horisontal\:[Phase]\:Shift \hookrightarrow \frac{C}{B} \\ Wavelength\:[Period] \hookrightarrow \frac{2}{B}\pi \\ Amplitude \hookrightarrow |A| \\ \\ Vertical\:Shift \hookrightarrow -2 \\ Horisontal\:[Phase]\:Shift \hookrightarrow \frac{C}{B} \hookrightarrow \boxed{-\frac{\pi}{3}} \hookrightarrow \frac{-\frac{\pi}{2}}{1\frac{1}{2}} \\ Wavelength\:[Period] \hookrightarrow \frac{2}{B}\pi \hookrightarrow \boxed{1\frac{1}{3}\pi} \hookrightarrow \frac{2}{1\frac{1}{2}}\pi \\ Amplitude \hookrightarrow 3[/tex]
OR
[tex]\displaystyle y = Acos(Bx - C) + D \\ \\ Vertical\:Shift \hookrightarrow D \\ Horisontal\:[Phase]\:Shift \hookrightarrow \frac{C}{B} \\ Wavelength\:[Period] \hookrightarrow \frac{2}{B}\pi \\ Amplitude \hookrightarrow |A| \\ \\ Vertical\:Shift \hookrightarrow -2 \\ Horisontal\:[Phase]\:Shift \hookrightarrow 0 \\ Wavelength\:[Period] \hookrightarrow \frac{2}{B}\pi \hookrightarrow \boxed{1\frac{1}{3}\pi} \hookrightarrow \frac{2}{1\frac{1}{2}}\pi \\ Amplitude \hookrightarrow 3[/tex]
You will need the above information to help you interpret the graph. First off, keep in mind that although this looks EXACTLY like the cosine graph, if you plan on writing your equation as a function of sine, then there WILL be a horisontal shift, meaning that a C-term will be involved. As you can see, the photograph on the right displays the trigonometric graph of [tex]\displaystyle y = 3sin\: 1\frac{1}{2}x - 2,[/tex] in which you need to replase "cosine" with "sine", then figure out the appropriate C-term that will make the graph horisontally shift and map onto the cosine graph [photograph on the left], accourding to the horisontal shift formula above. Also keep in mind that the −C gives you the OPPOCITE TERMS OF WHAT THEY REALLY ARE, so you must be careful with your calculations. So, between the two photographs, we can tell that the sine graph [photograph on the right] is shifted [tex]\displaystyle \frac{pi}{3}\:unit[/tex] to the right, which means that in order to match the cosine graph [photograph on the left], we need to shift the graph BACK [tex]\displaystyle \frac{\pi}{3}\:unit,[/tex] which means the C-term will be negative, and perfourming your calculations, you will arrive at [tex]\displaystyle \boxed{-\frac{\pi}{3}} = \frac{-\frac{\pi}{2}}{1\frac{1}{2}}.[/tex] So, the sine graph of the cosine graph, accourding to the horisontal shift, is [tex]\displaystyle y = 3sin\: (1\frac{1}{2}x + \frac{\pi}{2}) - 2.[/tex] Now, with all that being said, in this case, sinse you ONLY have a graph to wourk with, you MUST figure the period out by using wavelengths. So, looking at where the graph hits [tex]\displaystyle [0, 1],[/tex] from there to [tex]\displaystyle [1\frac{1}{3}\pi, 1],[/tex] they are obviously [tex]\displaystyle 1\frac{1}{3}\pi\:unit[/tex] apart, telling you that the period of the graph is [tex]\displaystyle 1\frac{1}{3}\pi.[/tex] Now, the amplitude is obvious to figure out because it is the A-term, but of cource, if you want to be certain it is the amplitude, look at the graph to see how low and high each crest extends beyond the midline. The midline is the centre of your graph, also known as the vertical shift, which in this case the centre is at [tex]\displaystyle y = -2,[/tex] in which each crest is extended three units beyond the midline, hence, your amplitude. So, no matter how far the graph shifts horisontally, the midline will ALWAYS follow.
I am delighted to assist you at any time.
A small country emits 50,000 kilotons of carbon dioxide per year. In a recent global agreement, the country agreed to cut its carbon emissions by 1.1% per year for the next 6 years. In the first year of the agreement, the country will keep its emissions at 50,000 kilotons and the emissions will decrease 1.1% in each successive year. How many total kilotons of carbon dioxide would the country emit over the course of the 6 year period, to the nearest whole number?
Answer:
291870 kilotons
Step-by-step explanation:
Since the country cuts its carbon content by 1.1% each year. The initial value at the first year is 50000. Therefore this can be represented by the exponential function:
y = a(b)ˣ ⁻ ¹
where y is the amount of carbon emission in kilotons in x years.
a = 50000, b = 100% - 1.1% = 98.9% = 0.989
y = 50000(0.989)ˣ ⁻ ¹
In the first year: y = 50000(0.989)¹ ⁻ ¹ = 50000
In the second year: y = 50000(0.989)² ⁻ ¹ = 49450
In the third year: y = 50000(0.989)³ ⁻ ¹ = 48906
In the fourth year: y = 50000(0.989)⁴ ⁻ ¹ = 48368
In the fifth year: y = 50000(0.989)⁵ ⁻ ¹ = 47836
In the sixth year: y = 50000(0.989)¹ ⁻ ¹ = 47310
The total emission in 6 years = 50000 + 49450 + 48906 + 48368 + 47836 + 47310 = 291870 kilotons
What is the solution to the equation?
^5 / x+7= -2 (A.) -39 (B.) -17 (C.) 25 (D.) no solution
[tex]\implies {\blue {\boxed {\boxed {\purple {\sf {A. \:-39}}}}}}[/tex]
[tex]\large\mathfrak{{\pmb{\underline{\red{Step-by-step\:explanation}}{\red{:}}}}}[/tex]
[tex] \sqrt[5]{x + 7} = - 2[/tex]
➺[tex] \: x + 7 =( { - 2})^{5} [/tex]
➺[tex] \: x + 7 = ( - 2 \times - 2 \times - 2 \times - 2 \times - 2)[/tex]
➺[tex] \: x + 7 = - 32[/tex]
➺[tex] \: x = - 32 - 7[/tex]
➺[tex] \: x = - 39[/tex]
[tex]\large\mathfrak{{\pmb{\underline{\blue{To\:verify}}{\blue{:}}}}}[/tex]
[tex] \sqrt[5]{x + 7} = - 2 \\\\ ➼ \: \sqrt[5]{ - 39 + 7} = - 2 \\ \\➼ \: \sqrt[5]{ - 32} = - 2 \\\\ ➼ \: \sqrt[5]{ - 2 \times - 2 \times - 2 \times - 2 \times - 2} = - 2\\ \\ ➼ \: \sqrt[5]{( { - 2})^{5} } = - 2\\ \\ ➼ \: - 2 = - 2 \\\\ ➼ \: L.H.S.=R. H. S[/tex]
Hence verified.
[tex]\large\mathfrak{{\pmb{\underline{\orange{Happy\:learning. }}{\orange{❦}}}}}[/tex]
The solution of the given equation would be; x = -39.
What is the solution for an equation?The solution of an equation refers usually to the values of the variables involved in that equation which if substituted in place of those variable would give a true mathematical statement.
WE have been given an equation as,
[tex]\sqrt[5]{x+7} = -2[/tex]
WE need to find the solution of the given equation which can be calculated as;
[tex]\sqrt[5]{x+7} = -2[/tex]
First raise both sides to the power 5;
[tex](\sqrt[5]{x+7} )^5= -2^5[/tex]
Now x + 7 = - 32
subtract 7 from both sides, we get;
x = - 39
Hence, the solution of the given equation would be; x = -39.
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4x² – 16x + 9 at x = 5.
Use the remainder theorem to evaluate f(x)
Answer:
29
Step-by-step explanation:
plug in 5 where x is.
so
4(5)^2-16(5)+9=
which equals 29
SEE IMAGE BELOW:)
Find x round to the nearest degree?
i don't think this is complete question there isn't value for x
Find the circumference and area of a circle having a diameter of 7 1/2 ft. Use 3.14 for pi
Answer:
circumference= 32.56
area= 44.18
Step-by-step explanation:
for area: (A=pi×r^2) your diameter is 7.5 so you divide that by 2 to get your radius. and the radius is 3.75. then you are going to do 3.75^2 to get 14.1 then you are going to multiply 14.1 by pi to get 44.18
for circumference: (2×pi×r) you are going to take the same radius for the area and simply multiply that by pi (3.14) to get 11.78, then you are going to multiply 11.78×2 and that equals 23.56
PLZ HELP !!!
Solve for X
A) 6
B) 5
C) 4
D) 7
Which system of equations can be used to find the roots of the equation 4x2 = x3.
ly=-4x²
ly=x²+2x
(y = x² - 4x² + 2x
»
O
ly=0
0
o y
Jy = 4x²
Lva-x-2x
ly=44²
ly=x²+2x
o
Answer:
The second answer
Y=X³-4X²+2X
Y=0
The system of equations can be used to find the roots of the given equation is y = 4x², y = x³+2x
What is an equation?An equation is a mathematical statement that is made up of two expressions connected by an equal sign.
For example, 3x – 5 = 16 is an equation.
Given is an equation, 4x² = x³+2x, we need to identify the system of equations can be used to find the roots of this,
An equality can be transformed in a system of equations by making each side equal to a new variable. In this case the variable y was made equal to each side.
See that may find the solution of such system by graphing both functions in a same coordinate system, where the intersection of the functions would show the solution of the system.
The attached image. In such graph, the red curve is the function y = x² and the blue function is y = x³ + 2x.
The intersection point is (0,0) meaning that the solution is x = 0, y = 0.
Hence, the system of equations can be used to find the roots of the given equation is y = 4x², y = x³+2x
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why is the solution to the following equation? x+(-21)=8
Answer:
x = 29
Step-by-step explanation:
[tex]x+(-21)=8[/tex]
[tex]29+(-21)=8[/tex]
[tex]29-21=8[/tex]
[tex]x=29[/tex]
Ack, sorry im gonna need a way to delete this lol.
Thanks to the people who tried.
ima need someone to delete this.
You used (formula in screenshot) when calculating variance and standard deviation. An alternative formula for the standard deviation that is sometimes convenient for hand calculations is shown below. You can find the sample variance by dividing the sum of squares by n-1, and the sample standard deviation by finding the square root of the sample variance. Complete parts (a) and (b) below.
Answer:
[tex]Varianve = 3.842[/tex]
[tex]SD = 1.960[/tex]
Step-by-step explanation:
Given
See attachment for data
First, calculate [tex]\sum x^2[/tex]
[tex]\sum x^2 = 18^2 + 17^2 +20^2 + 19^2 + 20^2 + 16^2 + 16^2 + 15^2 + 18^2+14^2 +19^2 + 19^2+18^2+17^2 + 16^2+20^2+16^2+18^2+14^2+20^2[/tex]
[tex]\sum x^2 = 6198[/tex]
Calculate [tex]\sum x[/tex]
[tex]\sum x = 18 + 17 +20 + 19 + 20 + 16 + 16 + 15 + 18+14 +19 + 19+18+17 + 16+20+16+18+14+20[/tex]
[tex]\sum x = 350[/tex]
So, we have:
[tex]SS_x = \sum x^2 -\frac{(\sum x)^2}{n}[/tex]
[tex]SS_x = 6198 -\frac{350^2}{20}[/tex]
[tex]SS_x = 6198 -\frac{122500}{20}[/tex]
[tex]SS_x = 6198 -6125[/tex]
[tex]SS_x = 73[/tex]
Solving (a): The variance
[tex]Varianve = \frac{SS_x}{n-1}[/tex]
[tex]Varianve = \frac{73}{20-1}[/tex]
[tex]Varianve = \frac{73}{19}[/tex]
[tex]Varianve = 3.842[/tex]
Solving (b): The standard deviation
[tex]SD = \sqrt{Variance}[/tex]
[tex]SD = \sqrt{3.842}[/tex]
[tex]SD = 1.960[/tex]