Step-by-step explanation:
Pythagoras Theorem
If the sum of the squares of the smaller two sides is equal to the square if the third side then it is a right triangle
[tex] {a}^{2} + {b}^{2} = {c}^{2} [/tex]
So, (5)^2 + (12)^2
is 25 + 144 = 169
Which is equal to (13)^2 which is also 169
The sides of the given triangle follows pythagoras theorem, therefore it is a right triangle
Hope it helps:)
Answer:
Pythagorean theorem
Step-by-step explanation:
We can explain it using the Pythagorean theorem. Right triangles always have a hypotenuse which is the longest side. That means 13 must be the hypotenuse of the triangle. The Pythagorean theorem is a^2+b^2=c^2
We already know all the values since every side is given so we just fill it in.
5^2+12^2=13^2
25+144=169
169=169
It is a right triangle
Next, the students at the Pearson Cooking Academy are assigned a take-home written exam to assess their knowledge of all things culinary. Historically, students scores on this exam had a N(68, 36) distribution. However, these days, there is an company called Charred Egg that offers to help students on tasks whether or not the exercises are for homework or for exams. In a cohort of 19 students, what is the probability that their average score will be at least 70?
Answer:
The probability is [tex]P( \= X \ge 70 ) = 0.07311[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 68[/tex]
The standard deviation is [tex]\sigma = \sqrt{36} = 6[/tex]
The sample size is [tex]n = 19[/tex]
Generally the standard error of the mean is mathematically represented as
[tex]\sigma_{\= x } = \frac{\sigma }{\sqrt{n} }[/tex]
=> [tex]\sigma_{\= x } = \frac{6 }{\sqrt{19} }[/tex]
=> [tex]\sigma_{\= x } = 1.3765[/tex]
Generally the probability that their average score will be at least 70 is mathematically represented as
[tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - P(\frac{ \= X - \mu }{\sigma_{\= x}} < \frac{70 - 68}{ 1.3765} )[/tex]
Generally [tex]\frac{ \= X - \mu }{\sigma_{\= x}} = z(The \ z-score \ of \ \= X )[/tex]
So
[tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - P(Z <1.453 )[/tex]
From the z-table
[tex]P(Z <1.453 ) = 0.92689[/tex]
=> [tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - 0.92689[/tex]
=> [tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 0.07311[/tex]
=> [tex]P( \= X \ge 70 ) = 0.07311[/tex]
Does coordinate x or coordinate y represent a greater number?
Answer:
Y
Step-by-step explanation:
You see that (x,3) and (2,7) are on the exact same x-value, which is 2. Y, on the other hand, is on the same y-value as (4,3), so it's going to be 4. 4 > 2, so your answer is y.
Y represents the greater number.
We see that (x,3) and (2,7) are on the exact same x-value, which is 2. Y, on the other hand, is on the same y-value as (4,3), so it's going to be 4. 4 > 2, so your answer is y.
What is an example of a coordinate?A set of values that display an actual role. On graphs it is also a pair of numbers: the first variety indicates the gap along, and the second variety indicates the distance up or down. As an example, the factor (12,5) is 12 units long, and five units up.
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83=4k-7(1+7k) How to solve
Answer:
k = -2
Step-by-step explanation:
83=4k-7(1+7k)
Distribute
83=4k-7-49k
Combine like terms
83 = -45k -7
Add 7 to each side
83+7 = -45k-7+7
90 = -45k
Divide each side by -45
90/-45 = -45k/-45
-2 = k
Answer:
k = -2Step-by-step explanation:
Step 1: Use 7 to open the bracket :
-7(1+7k)=-7-49k
Step 2: Collect like terms
Step 3 : Divide both sides of the equation by -45
[tex]83=4k-7(1+7k) \\ \\83 = 4k-7-49k\\\\ 83+7=4k-49k\\\\90 = -45k\\\\\frac{90}{-45} = \frac{-45k}{-45} \\\\k = -2[/tex]
Solve the right triangle.
a = 3.3 cm, b = 1.7 cm, C = 90°
Round values to one decimal place.
Answer:
A = 62.7°B = 27.3°c = 3.7Step-by-step explanation:
tan(A) = a/b = 3.3/1.7
A = arctan(33/17) ≈ 62.7°
B = 90° -A = 27.3°
c = √(a²+b²) = √(3.3² +1.7²) = √13.78
c ≈ 3.7
Find the limit, if it exists. (If an answer does not exist, enter DNE.) lim (x, y, z)→(7, 0, 2) e−xysin π z 4
Answer:
The limit of the function is 0Step-by-step explanation:
Given the limit of the function [tex]\lim_{(x,y,z) \to (7,0,2)} e^{-xy}sin\dfrac{\pi z}{4} }[/tex]
First step is to substitute the given values of x, y and z into the function given as shown;
[tex]\lim_{(x,y,z) \to (7,0,2)} e^{-xy}sin\dfrac{\pi z}{4} }\\\\= e^{-(7)(0)}sin\dfrac{\pi (2)}{4} }\\\\\\= e^{-0}sin\dfrac{\pi}{2} }\\\\\\= 1*sin\frac{\pi}{2} \\\\= 1*sin90^0\\\\= 1* 0\\\\= 0[/tex]
The limit therefore exist since the limit of the function at the given point gave us a finite value which is zero.
Aiko and Kendra arrive at the Texas
State Fair with $60. What is the total
number of rides they can go on if
they each pay the entrance fee of
$17 and rides cost $3 each?
Answer:
They can go on 14 rides the maximum.
Step-by-step explanation:
First, you have to set up the equation. Basically, Aiko and Kendra only carry $60 with them. They cannot go over that limit. Furthermore, the entrance free is $17. Each ride is $3.
(x = the amount of rides)
17 + 3x ≤ 60
17 represents the entrance fee which only has to be paid one time. 3x represents the cost of each ride (x equals to the amount of rides).
Now you solve.
Isolate the variable, which is 3x.
3x ≤ 60 - 17
3x ≤ 43
Now, divide 43 by 3 to find the value of x.
x ≤ 43 ÷ 3
x ≤ 14.3333333333
They can go on a max of 14 rides. Anymore, and they will go over budget. Normally, with problems like this one, if you have a decimal, you should round down unless your instructor says otherwise.
After all, who would you be able to go on a third of a ride? It isn't possible, so generally, they just have you round down.
Emma rents a car from a company that rents cars by the hour. She has to pay an initial fee of $75, and then they charge her $9 per hour. Write an equation for the total cost if Emma rents the car for ℎ hours. If Emma has budgeted $250 for the rental cars, how many hours can she rent the car? Assume the car cannot be rented for part of an hour.
PLEASE HELP !! (2/5) -50 POINTS-
Answer:
3 -1 -2
5 1 6
Step-by-step explanation:
An augmented system has the coefficients for the variables and then the solution going across
Rewriting the equations to get them in the form
ax + by = c
-3x+y =2
3x-y =-2
5x+y = 6
The matrix is
3 -1 -2
5 1 6
What is the first step in mathematical induction?
Answer:
Show that the statement is true for n=1
Step-by-step explanation:
Hey,
Show that the statement is true for n=1
You can check my other answer there which explains a little bit more the ideas.
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the fourth term of an AP is 5 while the sum of the first 6 terms is 10. Find the sum of the first 19 terms
Answer: S₁₉ = 855
Step-by-step explanation:
T₄ = a + ( n - 1 )d = 5 , from the statement above , but n = 4
a + 3d = 5 -------------------------1
S₆ = ⁿ/₂[(2a + ( n - 1 )d] = 10, where n = 6
= ⁶/₂( 2a + 5d ) = 10
= 3( 2a + 5d ) = 10
= 6a + 15d = 10 -----------------2
Now solve the two equation together simultaneously to get the values of a and d
a + 3d = 5
6a + 15d = 10
from 1,
a = 5 - 3d -------------------------------3
Now put (3) in equation 2 and open the brackets
6( 5 - 3d ) + 15d = 10
30 - 18d + 15d = 10
30 - 3d = 10
3d = 30 - 10
3d = 20
d = ²⁰/₃.
Now substitute for d to get a in equation 3
a = 5 - 3( ²⁰/₃)
a = 5 - 3 ₓ ²⁰/₃
= 5 - 20
a = -15.
Now to find the sum of the first 19 terms,
we use the formula
S₁₉ = ⁿ/₂( 2a + ( n - 1 )d )
= ¹⁹/₂( 2 x -15 + 18 x ²⁰/₃ )
= ¹⁹/₂( -30 + 6 x 20 )
= ¹⁹/₂( -30 + 120 )
= ¹⁹/₂( 90 )
= ¹⁹/₂ x 90
= 19 x 45
= 855
Therefore,
S₁₉ = 855
Factorise the following using the Difference of Two Squares or Perfect Squares rule: a) (2x-2)^2 - (x+4)^2 b) (3x+4) (3x-4)
Answer:
Step-by-step explanation:
Hello, please consider the following.
a)
[tex](2x-2)^2 - (x+4)^2 \\\\=(2x-2-(x+4))(2x-2+x+4)\\\\=(2x-2-x-4)(3x+2)\\\\=\boxed{(x-6)(3x+2)}[/tex]
b)
[tex](3x+4) (3x-4)\\\\=(3x)^2-4^2\\\\=\boxed{9x^2-16}[/tex]
Thank you.
1 - Dada a função f(x)= -Ix²-5x+4I, determine o valor de função para x = -1. * 1 ponto a) -10 b) 10 c) 9 d) -9 e) -8
Option a) -10
[tex] f(x)=-|x^2-5x+4|[/tex]
put $x=-1$
$f(-1)=-|(-1)^2-5(-1)+4|$
$\implies f(-1)=-|1+5+4|=-|10|=10$
Answer:
option a
Step-by-step explanation:
Option a) -10
put $x=-1$
$f(-1)=-|(-1)^2-5(-1)+4|$
$\implies f(-1)=-|1+5+4|=-|10|=10$
(x+1)(x−1)(x−5)=0 HELP
Answer:
x³ - 5x² - x + 5
Step-by-step explanation:
(x+1)(x-1)(x-5) = 0
fisrt step:
(x+1)(x-1) = x*x + x*-1 + 1*x + 1*-1 = x² - x + x - 1 = x² - 1
then:
(x+1)(x-1)(x-5) = (x²-1)(x-5)
(x²-1)(x-5) = x²*x + x²*-5 -1*x -1*-5 = x³ - 5x² - x + 5
A cardboard box without a lid is to be made with a volume of 4 ft 3 . Find the dimensions of the box that requires the least amount of cardboard.
Answer:
2ft by 2ft by 1 ftStep-by-step explanation:
Total surface of the cardboard box is expressed as S = 2LW + 2WH + 2LH where L is the length of the box, W is the width and H is the height of the box. Since the cardboard box is without a lid, then the total surface area will be expressed as;
S = lw+2wh+2lh ... 1
Given the volume V = lwh = 4ft³ ... 2
From equation 2;
h = 4/lw
Substituting into r[equation 1;
S = lw + 2w(4/lw)+ 2l(4/lw)
S = lw+8/l+8/w
Differentiating the resulting equation with respect to w and l will give;
dS/dw = l + (-8w⁻²)
dS/dw = l - 8/w²
Similarly,
dS/dl = w + (-8l⁻²)
dS/dw = w - 8/l²
At turning point, ds/dw = 0 and ds/dl = 0
l - 8/w² = 0 and w - 8/l² = 0
l = 8/w² and w =8/l²
l = 8/(8/l² )²
l = 8/(64/I⁴)
l = 8*l⁴/64
l = l⁴/8
8l = l⁴
l³ = 8
l = ∛8
l = 2
Hence the length of the box is 2 feet
Substituting l = 2 into the function l = 8/w² to get the eidth w
2 = 8/w²
1 = 4/w²
w² = 4
w = 2 ft
width of the cardboard is 2 ft
Since Volume = lwh
4 = 2(2)h
4 = 4h
h = 1 ft
Height of the cardboard is 1 ft
The dimensions of the box that requires the least amount of cardboard is 2ft by 2ft by 1 ft
nick used 1 3/4 kg of salt to melt the ice on his sidewalk. He then used another 3 4/5 kg on the driveway. How much salt did he use in all?
Answer:
5 11/20
Step-by-step explanation:
1 3/4 + 3 4/5
Get a common denominator of 20
1 3/4 * 5/5 + 3 4/5 *4/4
1 15/20 + 3 16/20
4 31/20
Rewriting
4 + 20/20 + 11/ 20
4+1 + 11/20
5 11/20
The sum of the reciprocals of two consecutive even integers is 3/4
Find the two integers.
[tex] \Large{ \underline{ \underline{ \bf{ \orange{Solution:}}}}}[/tex]
Let one of those even numbers be x, Then other even number would be x + 2.
According to question,
⇛ Their reciprocal add upto 3/4
So, we can write it as,
⇛ 1/x + 1/x + 2 = 3/4
⇛ x + 2 + x / x(x + 2) = 3/4
⇛ 2x + 2 / x² + 2x = 3/4
Cross multiplying,
⇛ 3(x² + 2x) = 4(2x + 2)
⇛ 3x² + 6x = 8x + 8
⇛ 3x² - 2x - 8 = 0
⇛ 3x² - 6x + 4x - 8 = 0
⇛ 3x(x - 2) + 4(x - 2) = 0
⇛ (3x + 4)(x - 2) = 0
Then, x = -4/3 or 2
☃️ It can't be -4/3 because it is fraction and negative number. So, x = 2
Then, x + 2 = 4
✤ So, The even numbers are 2 and 4.
━━━━━━━━━━━━━━━━━━━━
A lottery exists where balls numbered 1 to "20" are placed in an urn. To win, you must match the balls chosen in the correct order. How many possible outcomes are there for this game?
Answer: 1860480
Step-by-step explanation:
Initially, there are 20 balls where 5 must be chosen in order.
The number of possible outcomes may be calculated using the concept of permutations.
The formula for permutations is:
nPr =n!/(n−r)!
where n represents the number of items and r represents the number of items to be selected.
The number of ways of selecting 5 balls in order out of 20 is:
20P5 = 20!/15!
= 1860480
To conclude, there are 1860480 possible outcomes.
use the diagram to answer the question. AB corresponds to which line segment?
Answer:
DE
Step-by-step explanation:
I hope this helps!
Subtract 750 -389 plzzz help
When all possible differences between pairs of population means are evaluated not with an F test, but with a series of regular t tests, the probability of at least one:
Answer:
When all possible differences between pairs of population means are evaluated not with an F test, but with a series of regular t tests, the probability of at least one:
A. type I error is larger than the specified level of significance.
B. type II error is larger than the specified level of significance.
C. type I error is smaller than the specified level of significance.
D. type II error is smaller than the specified level of significance.
Answer : Type I error is larger than the specified level of significance.( A )
Step-by-step explanation:
An F test is a test that is used to test whether the variances between pairs of populations are equal while a T test is a test used to check if a pair of population are equal not considering the fact that the variances of the population are different .
When a T test is used to evaluate all possible differences between pairs of population instead of F test there is a probability of atleast one type 1 error larger than the specified level of significance.
solve the equation for 3x=24 for x
Answer:
8
Step-by-step explanation:
3x = 24
Divide both sides by 3
3x/3 = 24/3
x = 8
The solution for x in the equation, 3x = 24 is 8.
What is the answer for the equation?To solve the equation 3x = 24 for x, we need to isolate x on one side of the equation. Here's how we can do that:
Start with the equation 3x = 24.
Divide both sides of the equation by 3 to isolate x. This gives us (3x)/3 = 24/3.
Simplify the equation: x = 8.
Therefore, the solution to the equation 3x = 24 is x = 8.
This means that if we substitute x with 8 in the original equation, we get 3(8) = 24, which is true.
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Suppose that two.integers from the set of 8 integrs {1,2,3....8} are chosen at random. Find the probability that i. both numbers match. ii. Sun of the two numbers picked is less than 4?
Answer: a) 0.003
b) 0.125
c) 0.047
Step-by-step explanation:
We have a set of 8 numbers {1,2,...,8}
Let's analyze each case:
a) 5 and 8 are picked. The probability here is:
In the first selection, we have two possible picks (we can pick 5 or 8), so we have two possible outcomes out of 8 total outcomes, the probability for the first selection is:
P = 2/8 = 1/4.
Now, if one of those numbers was picked in the first selection, only one outcome is possible in this second selection, (if before we picked a 5, here we only can pick an 8, or if in the first selection we picked an 8, here we only can pick a 5.)
the probability is:
P = 1/8
The joint probability is equal to the product of the individual probabilities, so here we have:
P = (1/4)*(1/8) = 1/32 = 0.003
b) The numbers match (we draw two sixes, for example) :
In the first selection, we can have any outcome (the only requirement is that in the second selection we pick the same outcome), so the probability is:
P = 8/8 = 1
in the second selection, we can have only one outcome, so here the probability is:
P = 1/8
The joint probability is p = 1/8 = 0.125
c) The sum is smaller than 4:
The combinations are:
1 - 1 , 1 - 2 and 2 - 1
We have 3 combinations, and the total number of possible combinations is:
8 options for the first number and 8 options for the second selection:
8*8 = 64
The probability is equal to the number of outcomes that satisfy the sentence (3) divided by the total number of outcomes (64):
P = 3/64 = 0.047
(1 point) Consider the function f(x)=2x3−9x2−60x+1 on the interval [−4,9]. Find the average or mean slope of the function on this interval. Average slope: By the Mean Value Theorem, we know there exists at least one value c in the open interval (−4,9) such that f′(c) is equal to this mean slope. List all values c that work. If there are none, enter none . Values of c:
Answer: c = 4.97 and c = -1.97
Step-by-step explanation: Mean Value Theorem states if a function f(x) is continuous on interval [a,b] and differentiable on (a,b), there is at least one value c in the interval (a<c<b) such that:
[tex]f'(c) = \frac{f(b)-f(a)}{b-a}[/tex]
So, for the function f(x) = [tex]2x^{3}-9x^{2}-60x+1[/tex] on interval [-4,9]
[tex]f'(x) = 6x^{2}-18x-60[/tex]
f(-4) = [tex]2.(-4)^{3}-9.(-4)^{2}-60.(-4)+1[/tex]
f(-4) = 113
f(9) = [tex]2.(9)^{3}-9.(9)^{2}-60.(9)+1[/tex]
f(9) = 100
Calculating average:
[tex]6c^{2}-18c-60 = \frac{100-113}{9-(-4)}[/tex]
[tex]6c^{2}-18c-60 = -1[/tex]
[tex]6c^{2}-18c-59 = 0[/tex]
Resolving through Bhaskara:
c = [tex]\frac{18+\sqrt{1740} }{12}[/tex]
c = [tex]\frac{18+41.71 }{12}[/tex] = 4.97
c = [tex]\frac{18-41.71 }{12}[/tex] = -1.97
Both values of c exist inside the interval [-4,9], so both values are mean slope: c = 4.97 and c = -1.97
As a bowling instructor, you calculate your students' averages during tournaments. In 5 games, one bowler had the following scores: 143, 156, 172, 133, and 167. What was that bowler's average?
Answer:
154.2
Step-by-step explanation:
143 plus
156 plus
172 plus
133 plus
167 = 771
divide by 5 equals 154.2
A researcher is interested in finding a 90% confidence interval for the mean number of times per
day that college students text. The study included 147 students who averaged 44.7 texts per
day. The standard deviation was 17.9 texts. Round answers to 3 decimal places where possible.
a. To compute the confidence interval use a tv distribution.
b. With 90% confidence the population mean number of texts per day is between
and
texts.
Answer:
90% confidence the Population mean number of texts per day
(42.2561 ,47.1439)
Step-by-step explanation:
Step(i):-
Given sample size 'n' = 147
mean of the sample size x⁻ = 44.7
standard deviation of the sample 'S' = 17.9
90% confidence the Population mean number of texts per day
[tex](x^{-} - t_{\alpha } \frac{S}{\sqrt{n} } ,(x^{-} + t_{\alpha } \frac{S}{\sqrt{n} })[/tex]
Step(ii):-
Degrees of freedom
ν=n-1=147-1=146
t₀.₁₀ = 1.6554
[tex](x^{-} - t_{\alpha } \frac{S}{\sqrt{n} } ,(x^{-} + t_{\alpha } \frac{S}{\sqrt{n} })[/tex]
[tex](44.7 - 1.6554 \frac{17.9}{\sqrt{147} } ,(44.7 + 1.6554 \frac{17.9}{\sqrt{147} })[/tex]
(44.7 - 2.4439 ,44.7 + 2.4439 )
(42.2561 ,47.1439)
Conclusion:-
90% confidence the Population mean number of texts per day
(42.2561 ,47.1439)
Commute times in the U.S. are heavily skewed to the right. We select a random sample of 45 people from the 2000 U.S. Census who reported a non-zero commute time. In this sample the mean commute time is 25.2 minutes with a standard deviation of 19.1 minutes. Required:a. Can we conclude from this data that the mean commute time in the U.S. is less than half an hour?b. Conduct a hypothesis test at the 5% level of significance. c. What is the p-value for this hypothesis test?
Answer:
The mean commute time in the U.S. is less than half an hour.
Step-by-step explanation:
In this case we need to test whether the mean commute time in the U.S. is less than half an hour.
The information provided is:
[tex]n=45\\\bar x=25.5\\s=19.1\\\alpha =0.05[/tex]
(a)
The hypothesis for the test can be defined as follows:
H₀: The mean commute time in the U.S. is not less than half an hour, i.e. μ ≥ 30.
Hₐ: The mean commute time in the U.S. is less than half an hour, i.e. μ < 30.
(b)
As the population standard deviation is not known we will use a t-test for single mean.
Compute the test statistic value as follows:
[tex]t=\frac{\bar x-\mu}{s/\sqrt{n}}=\frac{25.2-30}{19.1/\sqrt{45}}=-1.58[/tex]
Thus, the test statistic value is -1.58.
(c)
Compute the p-value of the test as follows:
[tex]p-value=P(t_{(n-1)}<-1.58)=P(t_{(45-1)}<-1.58)=0.061[/tex]
*Use a t-table.
The p-value of the test is 0.061.
Decision rule:
If the p-value of the test is less than the significance level then the null hypothesis will be rejected and vice-versa.
p-value = 0.061> α = 0.05
The null hypothesis will not be rejected at 5% level of significance.
Thus, concluding that the mean commute time in the U.S. is less than half an hour.
If m2 DOC = 44º and m2 COB = 80°,
find the measure of the indicated arc in circle 0.
Find measure of arc DC.
Answer:
44°
Step-by-step explanation:
Given:
m<DOC = 44°
m<COB = 80°
Required:
Angle measure of arc DC
SOLUTION:
A central angle is said to be equal to the angle measure of the arc it intercepts or corresponds with. Therefore, angle measure of arc DC = m<DOC.
measure of arc DC = 44°
12-(3-9) 3*3 help please
Step-by-step explanation:
42 is your answer according to bodmas
What is 32 divided by the opposite of 4
Answer: -8
Since we are dividing the OPPOSITE of 4 then we are dividing 32÷-4
When multiplying or dividing a POSITIVE to a NEGATIVE you get a NEGATIVE
P/N=N
N/N=P
P*P=P
P=Positive
N=Negative
Divide
32/-4=-8
So your answer is -8
When 32 is divided by opposite of 4 the obtained result is - 8.
What is additive inverse ?Additive inverse of a number is such a number when the original number and it's additive inverse is added we get zero.
4 + ( - 4 ) = 0.So the additive inverse of 4 is - 4.
According to the given question we have to obtain the result when 32 is divided by opposite of 4.
Here opposite of 4 means additive inverse of 4 which is -4.
∴ 32/-4
= - 8.
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9. Find the mean of the following data :
Х
8
10
12
20
16
F
2
3
7
2
5
Answer:
[tex] \boxed{13.15}[/tex]Step-by-step explanation:
( See the attached picture )
Now,
Mean = [tex] \mathsf{\frac{Σfx}{n} }[/tex]
[tex] \mathsf{ = \frac{250}{19} }[/tex]
[tex] \mathsf{ = 13.15}[/tex]
------------------------------------------------------------------------
In the case of repeated data , follow the steps given below to calculate the mean :
Draw a table with 3 columnsWrite down the items ( x ) in ascending or descending order in the first column and the corresponding frequencies in the second column.Find the product of each item and it's frequency ( fx ) and write in the third column.Find the total of f column and fx column.Divide the sum of fx by the sum of f ( total number of items ) , the quotient is the required mean.Hope I helped!
Best regards!