Answer:
-5/2 because there is -5y/2 but we have to take coefficient only so -5/2
The Rockwell hardness of a metal is determined by impressing a hardened point into the surface of the metal and then measuring the depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normally distributed with mean 70 and standard deviation 3. (Rockwell hardness is measured on a continuous scale.)a. If a specimen is acceptable only if its hardness is between 67 and 75, what is the probability that a randomly chosen specimen has an acceptable hardness?b. If the acceptable range of hardness is (70-c, 70+c) , for what value of c would 95% of all specimens have acceptable hardness?c. If the acceptable range is as in part (a) and the hardness of each of ten randomly selected specimens is independently determined, what is the expected number of acceptable specimens among the ten?d. What is the probability that at most eight of ten independently selected specimens have a hardness of less than73.84? [Hint: Y = the number among the ten specimens with hardness less than 73.84 is a binomial variable; what is p?]
Answer:
a) The probability that a randomly chosen specimen has an acceptable hardness is 0.7938.
b) If the acceptable range of hardness is (70-c, 70+c), then the value of c would 95% of all specimens have an acceptable hardness of 5.88.
c) Expected number of acceptable specimens among the ten is 7.938.
d) Binomial with n = 10 and p = P(X < 73.84)
[tex]p = P(Z <(73.84 - 70) / 3 ) = P(Z < 1.28) = 0.8997\\\\P(X <= 8) = 1 - P(X = 9) - P(X = 10)\\= 0.2650635[/tex]
Step-by-step explanation:
a )
[tex]P(67 < X< 75) = P( (67 - 70) / 3 < X < (75 - 70) / 3 )\\\\= P( - 1 < Z < 1.67) = 0.9525 - 0.1587 = 0.7938[/tex]
b )
[tex]c = 1.96 * 3 = 5.88[/tex] { Since Z = 1.96 for 95% CI refer table.}
c )
Expected number of acceptable specimens among the ten [tex]= 10 * P(67 < X< 75) \\\\= 10 * 0.7938 = 7.938[/tex]
d )
Binomial with n = 10 and p = P(X < 73.84)
[tex]p = P(Z <(73.84 - 70) / 3 ) = P(Z < 1.28) = 0.8997\\\\P(X <= 8) = 1 - P(X = 9) - P(X = 10)\\= 0.2650635[/tex]
Name the types of angles shown.
Check all that apply
A supplementary angles
B straight angle
C complementary angle
D right angle
Answer: C) complementary angle and D) right angle
Step-by-step explanation:
A is wrong because supplementary angles add up to 180 and this shows a right angle not a straight line
B is wrong because this a right angle not a straight angle
C is correct because complementary angles are two angles that add up to 90 degrees. angle EFH is split into EFG and GFH which adds up to 90 degrees.
D is correct because you can see the right angle symbol for angle EFH
The given angles shown in the figure are right angles and complementary angles.
Supplementary angles are two angles that add up to 180 degrees.
A straight angle is an angle that measures exactly 180 degrees.
It is a straight line, so it forms a straight angle.
A complementary angle is a pair of angles that add up to 90 degrees.
∠EFG and ∠GFH together are complementary angles as their sum is 90 degrees.
A right angle is an angle that measures exactly 90 degrees.
∠EFH is a right angle.
To learn more on Angles click:
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If -9x(x + A) + 2 = (Bx + 2)(3x - 1) + 4, find the constants A and B.I am stuck at the step of solving B,can you help me?write down you steps and answer please
Answer:
A = -1
B = -3
Step-by-step explanation:
you need to do all the multiplication on both sides and then simply compare the factors of the various powers of x.
so,
-9x² - 9×A×x + 2 = 3×B×x² + 6x -Bx - 2 + 4
-9x² - 9×A×x + 2 = 3×B×x² + (6-B)x + 2
the x-less constants 2 = 2 are correct. now we need to compare the factors for the other parts of x.
we have left and right only one expression of x²
-9x² on the left
3×B×x² on the right
therefore,
-9 = 3×B
=> B = -3
otherwise the equation would not be correct for all values of x.
the only other parts remaining are
-9×A×x = (6-B)x = (6 - -3)x = (6+3)x = 9x
=>
-9×A = 9
-A = 1
A = -1
remember, all parts of the left and of the right side must be equal for the equation to be true in all cases.
Which expression is not equivalent to 8 + (n – 4)?
12+n
n+4
(8 + n) – 4
(8 – 4) +n
Answer: n+4
Step-by-step explanation:
Coal is carried from a mine in West Virginia to a power plant in New York in hopper cars on a long train. The automatic hopper car loader is set to put 59 tons of coal into each car. The actual weights of coal loaded into each car are normally distributed, with mean µ = 59 tons and standard deviation σ = 1.9 ton.a) What is the probability that one car chosen at random will have less than 49.5 tons of coal? b) What is the probability that 35 cars chosen at random will have a mean load weight of less than 49.5 tons of coal?
Answer:
b) What is the probability that 35 cars chosen at random will have a mean load weight of less than 49.5 tons of coal? (Round your answer to four decimal places.)
Step-by-step explanation:
PLEASE HELP WILL GIVE BRAINLIEST
Answer:
Check explanation
Step-by-step explanation:
I'll give you my way of solving it and you can figure it out from there.
<CEA = <DEB due to vertical angles
AE = ED due to midpoint theorem
<CAD = <ADB due to alternating angles theorem
thus two triangles congruent due to ASA
If you apply these changes to the linear parent function, f(x) = x, what is the
equation of the new function?
• Vertically compress by a factor of 7.
• Shift up 9 units.
O A. DY) = 7x+9
O B. g(x) = = x+9
O C. () = 7(x-9)
O D. g(x) = + (x+9)
Answer:
The equation of the new function is [tex]g(x) = 7x + 9[/tex]
Step-by-step explanation:
Vertically compress by a factor of 7.
Vertically compressing a function by a units is the same as:
[tex]g(x) = f(ax)[/tex]
In this question:
[tex]f(x) = x, a = 7[/tex]. So
[tex]g(x) = f(7x) = 7x[/tex]
Shift up 9 units.
Shifting a function up a units is the same thing as adding a to the function. In this case, [tex]a = 9[/tex], and then:
[tex]g(x) = 7x + 9[/tex]
The equation of the new function is [tex]g(x) = 7x + 9[/tex]
Which answer describes the pattern in this sequence?
2, 1, 12, 14, ...
multiply by 2
subtract 1
add 12
multiply by 12
Lines s and t are perpendicular. If the slope of line s is 5, what is the slope of line t
help pls
Draw a line segment AB=8cm. Construct angle BAC=angle ABC=60 DEGREE.
Now draw the angular bisector of each angle of angle ABC.
pls help
Answer:
Step-by-step explanation:
Bisection implies dividing a given segment into equal haves by construction. So that in the given question, angle ABC would be divided into equal parts.
After drawing segment AB to given length, use a compass to construct the required angle ABC. Then use the ends of the arc for the angle to bisect the angle.
The construction to this question is herewith attached to this answer for more clarifications.
find f(-2) for f(x)=3•2^x
Answer:
0.75 or 3/4
Step-by-step explanation:
f(-2) = 3•2^-2
f(-2) = 3•0.25
f(-2) = 0.75 or 3/4
Hope this helps! :)
Right angle Trigonometry, please help me solve and explain!
Answer:
5.01
Step-by-step explanation:
Reference angle (θ) = 24.3°
Length of side Opposite to reference angle = 2.06
Let the side length (Hypotenuse) we're looking for be represented as x
Apply SOH:
Sin θ = Opp/Hyp
Substitute the values into the equation
Sin 24.3° = 2.06/x
Multiply both sides by x
x × Sin 24.3° = 2.06/x × x
x × Sin 24.3° = 2.06
Divide both sides by Sin 24.3°
(x × Sin 24.3°)/Sin 24.3° = 2.06/Sin 24.3°
x = 5.01 (nearest hundredth)
find the volume of the cone 3.4 m x 5.5 m
Answer:
63,5
Step-by-step explanation:
pi r bình pnhân hươnh g
Can I have help I am stuck on this problem It would mean the world if u helped me and tysm!! =-)
Answer:
Step-by-step explanation:
Wage = rate / hr * the number of hours worked.
Wage = ?
rate = 15.45
time = 29.25 hours
Wage = 15.45 * 29.25
Wage = 451.91
Is AABC-ADEP? If so, identify the similarity postulate or theorem that
applies.
B
16
105°
5-105
4
36
A
C
D
9
F
I
Answer:
D. cannot be determined
Step-by-step explanation:
that is kind of a trick question.
right based on the given information none of the 3 methods can be applied.
we don't have all 3 sides for SSS
we don't have 2 angles for AA
and we don't have 2 sides with their included angle for SAS.
but it can still be determined (they ARE similar), as this is a special case of SSA, where it is clear that the corresponding congruent angles are located at the same position relatively to the corresponding similar lines.
you can discuss this with your teacher, if you are interested.
AND - we can easily determine any of the other missing pieces (side and angles). these missing pieces then will correspond exactly to their counterparts in the other triangle (the 2 angles in ABC are equal to the 2 angles in DEF, the missing sides file the same scaling factor as the other known sides). and then any of the 3 methods can be applied.
so, this is actually tricky ...
carol and jada sold raffle tickets to raise money for a new playground carol sold 2045 tickets jada sold 356 more than carol how many did jada sell
What is the slope of the line represented by the equation f(x) = -3x + 7?
A -7
B -3
C 3
D 7
Answer:
-3
Step-by-step explanation:
in these equations the slope is multiplied by x which is -3 in this one.
Answer:
[tex]-3[/tex]
Step-by-step explanation:
The equation of a line is [tex]y=mx+b[/tex], and m is the gradient which is the slope. Hence, the number with x is the slope, which is [tex]-3[/tex].
Hope that helped.
A team of researchers wants to determine whether pet owners are generally more satisfied with their lives than non-pet owners. To test their theory, the researchers randomly select 500 pet owners and 500 non-pet owners from several major metropolitan areas in the country. The researchers then interview the individuals, asking them a series of questions. Each response is assessed with a point value that is later translated to a satisfaction indicator. Of the pet owners surveyed, 380 of the 500 were found to be satisfied with their lives, while 336 of the 500 non-pet owners were found to be satisfied.
Would this study be considered an experiment or an observational study?
Answer:
observational study
Step-by-step explanation:
Chet has $1200 invested in a bank account modeled by the function P(n) = 1200(1.002)
Answer:
Answer: 3) R(n) = 1200(1.002)n - 100n
Step-by-step explanation:
After n months, which function represents Chet’s net worth, R(n)?
(1) R(n) = 1200(1.002)n + 100n
(2) R(n) = 1200(1.002)12n + 100n
(3) R(n) = 1200(1.002)n - 100n
(4) R(n) = 1200(1.002)12n - 100n
Answer: 3) R(n) = 1200(1.002)n - 100n
Net worth is the amount of his savings minus his debt,
Everything in the problem is in terms of months, so there is no need to multiply the exponent by 12, which would convert n years into months.
You have some marbles. When you make a shape of an equilateral triangle, you either have 4 extra, or you need 28 more to complete the shape. How many marbles do you have? How long is a side of the biggest equalateral triangle that you can make make with your marbles?
Answer:
You have 500 marbles.
The longest side of the biggest equalateral triangle that you can make with your marbles is 31
Step-by-step explanation:
28 + 4 = 32
So our equation is:
TR(32) - 28
Now find Triangular Number 32: (32 *33)/2=528
528 - 28 = 500
So, we have 500 marbles
Now we need to find the longest side of the biggest equalateral triangle that you can make make with your marbles
Let's go back to 28 + 4 = 32
One row above 32 is 31
So the longest side of the biggest equalateral triangle that you can make with your marbles is 31
Hope this helps!
A bag contains 6 black, 4 blue, and 8 white marbles. What is the probability that a marble drawn from the bag will be white?
a.1/18
b.2/5
c.4/9
d.4/5
Answer:
C.4/9
Step-by-step explanation:
You add the black marbles, blue marbles, and the white marbles together, which equal 18. Out of the 18 marbles, 8 of them are white so it would be 8/18.
but you have to simplify it. 8 and 18 have 2 as the greatest common factor. 8 divided by 2 is 4 and 18 divided by 2 is 9. Finally its 4/9 since you cant simplify it even more.
The side of an equilateral triangle is 12. Its area is
Select one:
a. 144
b. 72
c. 36 √3
d. 48
Answer:
area is 1/2bh
in an euqilateral triangle, all sides are equal so base and height are 12
1/2 x 12 x 12
1/2 x 144= 72 (B)
Answer: Choice C. [tex]36\sqrt{3}[/tex]
This is the same as writing 36*sqrt(3)
===================================================
Work Shown:
x = 12 = side length of equilateral triangle
A = area of equilateral triangle
A = 0.25*sqrt(3)*x^2
A = 0.25*sqrt(3)*12^2
A = 0.25*sqrt(3)*144
A = 0.25*144*sqrt(3)
A = 36*sqrt(3) .... answer is choice C
Side note: the area approximates to 62.354 square units.
giving brainliest to whomever answers correctly!
Answer:
B: A systematic random sample
Step-by-step explanation:
Systematic sampling is a type of probability sampling in which members of a larger population are chosen at random from a larger population but at a fixed, periodic interval. This interval, also known as the sampling interval, is calculated by dividing the population size by the sample size desired. Despite the fact that the sample population is chosen in advance, systematic sampling is still considered random if the periodic interval is set in advance and the starting point is chosen at random.
Hope this helps and if it does, don't be afraid to give my answer a "Thanks" and maybe a Brainliest if it's correct?
If we know the values of the sine and cosine of x and y, we can find the value of cos(x - y) by using the ____ Formula for Cosine. State the formula: cos(x - y) = ____.
Answer:
[tex]\cos(x - y) = \cos(x)\cos(y) + \sin(x)\sin(y)[/tex]
Step-by-step explanation:
Given
[tex]\cos(x - y)[/tex]
Required
State the formula
From trigonometry identity, the formula of [tex]\cos(x - y)[/tex] is:
[tex]\cos(x - y) = \cos(x)\cos(y) + \sin(x)\sin(y)[/tex]
The graph of an exponential function passes through (2,−12) and (3,−24). Find the exponential function that describes the graph.
no fancy math here, just some reasoning with words. I just feel like it
for one step in x-direction the value of the function doubles, so the common factor is 2.
so let's trace it back
(1,-6)
(0, -3)
For an exponential function the y-intercept is the "initial value".
do let's write is as a function
[tex]y = - 3 \times {2}^{x} [/tex]
you could also use the points and plug their numbers into the general formula, but I felt this explanation could give you more understanding, since it's meant to be more intuitive.
hope it helps
Triangle A B C is cut by line segment D E. Line segment D E goes from side A C to line A B. The length of A E is 12, the length of E B is 4, and the length of A D is 9. What is the length of Line segment D C? 2 units 3 units 6 units
Answer: The length of DC is 3 units
Step-by-step explanation:
The Basic proportionality theorem states that if a line is parallel to one side of a triangle and intersects the other two at different points, then the other two sides are divided in the same ratio.
The given image is attached below.
From the BPT theorem, we can say that:
[tex]\Rightarrow \frac{AE}{EB}=\frac{AD}{DC}[/tex]
We are given:
AE = 12 units
EB = 4 units
AD = 9 units
Putting values in above equation, we get:
[tex]\Rightarrow \frac{12}{4}=\frac{9}{DC}\\\\\Rightarrow DC=\frac{9\times 4}{12}\\\\\Rightarrow DC=3 units[/tex]
Hence, the length of DC is 3 units
Answer:
The answer is 3 units
Step-by-step explanation:
is the sum of two rational numbers sometimes zero ture or false?
Answer:
True.
Step-by-step explana
-4/5 + 4/5 is 0
Ms.James shared 5/8 of the candies she had in a bag and had 15 left.How many candies did she have before sharing?
Answer:
40
Step-by-step explanation:
If you take 15, and divide it by the 3 out of the 3/8 left, you get 5. You then multiply 5 by 8 to get the full amount of candies she had before sharing, 40.
I hope this helped!
Thanks!
Your friend in answering,
~Steve
Answer:
40.
Step-by-step explanation:
If 15 candies are the rest of 3/8, then the total candies were 40.
The ratio of girls to boys in a particular classroom is 8: 7. How many boys are in the class if there are 45 students?
ONLY ANSWER IF YOU KNOW THE ANSWER
9514 1404 393
Answer:
21
Step-by-step explanation:
Rearranging the given ratio, we can find the ratio of boys to the total.
boys : (boys +girls) = 7 : (7+8) = 7 : 15
Then the number of boys is ...
(7/15)(45) = 21
There are 21 boys in the classroom.
at the present time, gerald is eight less than five times his nephews age. seven years ago gerald was 9 times his nephews age.
(A)if g represents geralds age now and n represents his nephews age today. use a system of equations that could be used to model this scenario?
(B)than use the equations to determine algebraically the ages of both Gerald and his nephew.
(C)than determine in how many years Gerald will be three times as old as his nephew?
What you know about rollin' down in the deep?
When your brain goes numb, you can call that mental freeze
When these people talk too much, put that sh*t in slow motion, yeah
I feel like an astronaut in the ocean, ayy
What you know about rollin' down in the deep?
When your brain goes numb, you can call that mental freeze
When these people talk too much, put that sh*t in slow motion, yeah
I feel like an astronaut in the ocean
