Hurry quick i have more questions answer then all for a total of about 100 points

The probability that a randomly selected finishing time is greater than 80 seconds is 0.84.

Mean = 87

Standard deviation = 7

We convert this to standard normal as

P( X < x) = P( Z < x - Mean / SD)

Since, 80 = 87 - 7

80 is one standard deviation below the mean.

Using the empirical rule, about 68% of data falls between 1 standard deviation of the mean. So, 32% is outside the 1 standard deviation of the mean, and 16% is outside to either side.

We have to calculate P( X > 80) = ?

That is probability of all values excluding lower tail of the distribution.

P(X > 80) = 68% + 16%

= 84%

= 0.84

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9514 1404 393

Answer:

  OBADR

Step-by-step explanation:

The first two letters are swapped, and the last two letters are swapped.

  BOARD . . . becomes

  OBADR

Answer:

Step-by-step explanation:

Do you mean 27 units² ?

A cube has six congruent, square faces. Area of one face = (27/6) units²

Length of one edge = √(27/6)

= √(9/2)

= √9/√2

= 3/√2

= 3√2/2 units

Answer:

1) D(1,0), C(-2,-4)  or 2) D(9,0), C(6,-4)

Step-by-step explanation:

The vector AB is (2-5, -1-3)= (-3,-4)

The modul of the vector is equal to sqrt (3squared+4squared)=5 (the length of the side AB of square)

Explore the point D (the coordinates of the point is (x,0), y=o, because it is an axis x). AD (x-5, -3)

The modul of AD is sqrt ((x-5)^2+(-3)^2)= sqrt (x^2-10x+25+9), it is equal to the side AD which is equal to AB

sqrt(x^2-10x+34)= 5

x^2-10x+34=25

x^2-10x+9=0

x=1, x=9

D is (1,0) or D is (9,0),

find C, (for D1(1,0))

Find the midpoint of BD (O)

xo= (2+1)/2= 1.5

y0=(-1+0)/2= -0.5

It is the midpoint of Ac too

x0= (xa+xc)/2    1.5 = (5+xc)/2  xc= -2

y0=(ya+yc)/2      -0.5= (3+yc)/2   yc=-4

c(-2,-4)

Find C2 (for D(9,0))

Find the midpoint of BD (O)

x0= (2+9)/2=5.5

y0= (-1+0)/2=-0.5

o(5.5, -0.5)

It is the midpoint of Ac too

x0= (xa+xc)/2   5.5= (5+x)/2   x=6

y0=(ya+yc)/2    -0.5= (3+x)/2  y=-4

opposite angles are equal

[tex]\\ \sf\longmapsto 13x+19=84[/tex]

[tex]\\ \sf\longmapsto 13x=84-19[/tex]

[tex]\\ \sf\longmapsto 13x=65[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{65}{13}[/tex]

[tex]\\ \sf\longmapsto x=5[/tex]

Answer:

[tex]\boxed {\boxed {\sf x=5}}[/tex]

Step-by-step explanation:

We are asked to solve for x.

We are given a pair of intersecting lines and 2 angles measuring (13x+19)° and 84°. The angles are opposite each other, so they are vertical angles. This means they are congruent or have the same angle measure.

Since the 2 angles are congruent, we can set them equal to each other.

[tex](13x+19)=84[/tex]

Solve for x by isolating the variable. This is done by performing inverse operations.

19 is being added to 13x. The inverse operation of addition is subtraction. Subtract 19 from both sides of the equation.

[tex]13x+19-19= 84 -19[/tex]

[tex]13x= 84 -19[/tex]

[tex]13x=65[/tex]

x is being multiplied by 13. The inverse operation of multiplication is division. Divide both sides by 13.

[tex]\frac {13x}{13}= \frac{65}{13}[/tex]

[tex]x= \frac{65}{13}[/tex]

[tex]x= 5[/tex]

For this pair of vertical angles, x is equal to 5.

Answer:

-0.2, 1/3, 0.5

Step-by-step explanation:

A negative is a negative, making it the smallest answer. The 1/3 is 0.333 repeating, so that goes next and then theres 0.5!

Answer:

Selling price=rs.600.

Profit of rs=100.

Step-by-step explanation:

C.P=500; profit%=20%

S.P.=100+profit%×C.P/100

S.P=120×500/100

=rs.600

S.P>C.P

Profit S.P-C.P

600-500=100

he gained for rs.100.

Answer:

Step-by-step explanation:

Slope = -¼

y-intercept = -4

Slope-intercept equation for line:

y = -¼x - 4

Answer:

400

Step-by-step explanation:

First, the firm produces 100 sets its first year. This means that our equation starts at 100. Next, the total number of calculator sets in 5 years is 4500. With y₁ representing the amount of calculator sets produced during year 1, y₂ representing the amount of sets during year 2, and so on, we can say that

y₁+y₂+y₃+y₄+y₅ = 4500

100 + y₂+y₃+y₄+y₅ = 4500

Next, we are given that the production increases uniformly by an amount each year. Representing that amount as a, we can say that

y₁+a = y₂

y₂+a = y₃

y₁+a+a = y₃

y₁+ 2 * a = y₃

and so on, so we have

100 + y₂+y₃+y₄+y₅ = 4500

100 + (100+a) + (100+2a) + (100+3a) + (100+4a) = 4500

500 + 10a = 4500

subtract 500 from both sides to isolate the a and its coefficient

4000 = 10a

divide both sides by 15 to isolate a

a = 400

Answer:

B = 25050

Step-by-step explanation:

S=n/2(2a1+(n-1)d)

Answer:

A = 70 mm²

Step-by-step explanation:

The area (A) of a trapezoid is calculated as

A = [tex]\frac{1}{2}[/tex] h (b₁ + b₂)

where h is the perpendicular height and b₁, b₂ the parallel bases

Here h = 10, b₁ = 10, b₂ = 4 , then

A = [tex]\frac{1}{2}[/tex] × 10 × (10 + 4) = 5 × 14 = 70 mm²

Answer:

1/4

Step-by-step explanation:

The probability will be equal to 1 - (probability that it will not be inside the small circle) = 1 - (pi*4-pi)/(pi*4)=1/4

Answer:

The smallest amount is £6911

Step-by-step explanation:

Rate of Interest = R = 5% per year

Duration in years = n = 3 year

Amount expected after three years when compounded annually =  A = £8000

Formula for Amount of compound interest annually is a follows

A = P( 1 + R/100)^n

In our case Principal P = x , Amount A = 8000 , R = 5% and n = 3( since compounded annually). On substituting these values in above formula we get

8000 = x ( 1 + 5/100)^3

⇒8000 = x ( 105/100)^3

⇒8000 = x ( 21/20 )^3

⇒(8000 × 20 × 20 × 20)/(21×21×21) = x

⇒x = 6910.70≈6911

Answer:

(14,2) and (-6/5,-28/5)

Step-by-step explanation:

The distance, d, from two points (x,y) and another point (a,b) can be calculated using

d=sqrt((x-a)^2+(y-b)^2).

Our point (a,b) is (2,7) and d=13.

Making substitutions:

13=sqrt((x-2)^2+(y-7)^2)

We are also given the relation between x and y is given as x-2y=10.

Adding 2y to both sides gives: x=10+2y

Make this insertion into our equation:

13=sqrt((10+2y-2)^2+(y-7)^2)

Simplify inside:

13=sqrt((8+2y)^2+(y-7)^2)

Square both sides:

169=(8+2y)^2+(y-7)^2

Expand binomial squares:

169=64+32y+4y^2+y^2-14y+49

Combine like terms:

169=5y^2+18y+113

Subtract 169 on both sides:

0=5y^2+18y-56

We could try to factor

0=(5y+28)(y-2)

So y=2 or y=-28/5

Recall x=10+2y

So if y=2, then x=10+2(2)=10+4=14.

So if y=-28/5, then x=10+2(-28/5)=10+(-56/5)

=50/5 +-56/5

=-6/5.

So two points satisfying given criteria is

(14,2) and (-6/5,-28/5).

Answer/Step-by-step explanation:

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Answer:

C

Step-by-step explanation:

15x-10=80

15x=90

x=90/15, x=6

Answer:

x = 6

Step-by-step explanation:

15x - 10 = 80

Add 10 to each side

15x-10+10 = 80+10

15x = 90

Divide each side by 15

15x/15 = 90/15

x = 6

Answer:

y=2x-3

Step-by-step explanation:

4x-2y=3

-2y=3-4x

2y=4x-3

y=4x/2-3/2

y=2x-1.5  m1=2 (the number near x)

If the searched line is parallel to the line 4x−2y=3, m1=m2= 2

y=m2x+b - the searched line

1=2*2+b

b=-3

y=2x-3

Answer:

Step-by-step explanation:

x + y = 40

x>y

(11/2)y - (13/4)*x = - 25

x = 40 - y

(11/2)y - (13/4)(40-y) = - 25      multiply by 4

22y - 13( 40 - y) = - 100

22y - 520 + 13y = -400         Add 520

35y = 120

y = 120 / 35

y = 3 3/7

x = 40 - y

x = 36 4/7

Answer:

Bro what do you mean to represent Mount Everest height by x but if you want to sove a maths sum than you can take any alphabet

Step-by-step explanation:

If you like my answer than please mark me brainliest thanks

Answer:

Minimum = -1

Maximum = None

Step-by-step explanation:

The minimum is the lowest y value of a given function and the maximum is the highest y value. In this instance, the vertex is the minimum. This means the minimum value is -1. There is no maximum as the function seemingly increases forever.

ANSWER

8-2........3/4 but you have you ADD some people dont know that 8-2= 6

and so 6/1 + 3/4 is 24/4

Answer:

The p-value of the test is 0.0301 > 0.02, which means that there is not sufficient evidence at the 0.02 level to support the company's claim.

Step-by-step explanation:

The company's promotional literature claimed that under 64% fail in the first 1000 hours of their use.

At the null hypothesis, we test if the proportion is of at least 64%, that is:

[tex]H_0: p \geq 0.64[/tex]

At the alternative hypothesis, we test if the proportion is of less than 64%, that is:

[tex]H_1: p < 0.64[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

64% is tested at the null hypothesis:

This means that [tex]\mu = 0.64, \sigma = \sqrt{0.64*0.36}[/tex]

A sample of 900 computer chips revealed that 61% of the chips fail in the first 1000 hours of their use.

This means that [tex]n = 900, X = 0.61[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{0.61 - 0.64}{\frac{\sqrt{0.64*0.36}}{\sqrt{900}}}[/tex]

[tex]z = -1.88[/tex]

P-value of the test and decision:

The p-value of the test is the probability of finding a sample proportion below 0.61, which is the p-value of z = -1.88.

Looking at the z-table, z = -1.88 has a p-value of 0.0301.

The p-value of the test is 0.0301 > 0.02, which means that there is not sufficient evidence at the 0.02 level to support the company's claim.

Answer:

the last option [tex]x^{3}[/tex] + 1 / x

Step-by-step explanation:

first option's x has the power 3

second option's x has the power 1

third option's x has the power 1

but in the last option it has the power -1

polynomials doesn't support negative power

*remember

Answer:

just devide it. after that ÷ with 100 per time

Answer:

Step-by-step explanation:

The cost is:

Percentage gain:

Answer:

32

Step-by-step explanation:

The pattern is multiples of 4

The 8 term will be the 8 multiple of 4

4 * 8 = 32

Answer:

32

Step-by-step explanation:

We are adding 4 each time

an = a1+d(n-1)

an = 4+4(n-1)

we want the 8th term

a8 = 4+4(8-1)

a8 = 4+4(7)

a8 = 4+28

a8 = 32

Answer:

7x-5 = 9

x = 2

Step-by-step explanation:

Let x be the number

7x-5 = 9

Add 5 to each side

7x-5+5 = 9+5

Divide each side by 7

7x = 14

7x/7 = 14/7

x=2

Answer:

X-4x+11=8

-3x+12-8=0

-3x+4=0

3x=4

X=4/3

Answer:

x = 4/3 or 1.3

Step-by-step explanation:

Combine like terms

8 = -3x + 12

Move the terms

3x = 12 - 8

Calculate

3x = 4

Divide both sides by 3

x = 4/3

or

x = 1.3

a. The linear equation for the first point (-4,1) is 16A-4B+C=1

b. The linear equation for the second point (-2, 0.94) is 4A-2B+C=0.94

c. The linear equation for the third point (0,1) is 0A+0B+C=1

d. The matrix equation looks like this:

[tex]\left[\begin{array}{ccc}16&-4&1\\4&-2&1\\0&0&1\end{array}\right]*\left[\begin{array}{c}A\\B\\C\end{array}\right]=\left[\begin{array}{c}1\\0.94\\1\end{array}\right][/tex]

e. The inverse of the coefficient matrix looks like this:

[tex]A^{-1}=\left[\begin{array}{ccc}\frac{1}{8}&-\frac{1}{4}&\frac{1}{8}\\\frac{1}{4}&-1&\frac{3}{4}\\0&0&1\end{array}\right][/tex]

f. The equation of the parabola is: [tex]\frac{3}{200}x^{2}+\frac{3}{50}x+1=y[/tex]

a. In order to build a linear equation from the given points, we need to substitute them into the general form of the equation.

Let's take the first point (-4,1). When substituting it into the general form of the quadratic equation we end up with:

[tex](-4)^{2}A+(-4)B+C=1[/tex]

which yields:

[tex]16A-4B+C=1[/tex]

b. Let's take the second point (-2,0.94). When substituting it into the general form of the quadratic equation we end up with:

[tex](-2)^{2}A+(-2)B+C=0.94[/tex]

which yields:

[tex]4A-2B+C=0.94[/tex]

c. Let's take the third point (0,1). When substituting it into the general form of the quadratic equation we end up with:

[tex](0)^{2}A+(0)B+C=1[/tex]

which yields:

[tex]0A+0B+C=1[/tex]

d. A matrix equation consists on three matrices. The first matrix contains the coefficients (this is the numbers on the left side of the linear equations). Make sure to write them in the right order, this is, the numbers next to the A's should go on the first column, the numbers next to the B's should go on the second column and the numbers next to the C's should go on the third column.

The equations are the following:

16A-4B+C=1

4A-2B+C=0.94

0A+0B+C=1

So the coefficient matrix looks like this:

[tex]\left[\begin{array}{ccc}16&-4&1\\4&-2&1\\0&0&1\end{array}\right][/tex]

Next we have the matrix that has the variables, in this case our variables are the letters A, B and C. So the matrix looks like this:

[tex]\left[\begin{array}{c}A\\B\\C\end{array}\right][/tex]

and finally the matrix with the answers to the equations, in this case 1, 0.94 and 1:

[tex]\left[\begin{array}{c}1\\0.94\\1\end{array}\right][/tex]

so if we put it all together we end up with the following matrix equation:

[tex]\left[\begin{array}{ccc}16&-4&1\\4&-2&1\\0&0&1\end{array}\right]*\left[\begin{array}{c}A\\B\\C\end{array}\right]=\left[\begin{array}{c}1\\0.94\\1\end{array}\right][/tex]

e. When inputing the coefficient matrix in our graphing calculator we end up with the following inverse matrix:

[tex]A^{-1}=\left[\begin{array}{ccc}\frac{1}{8}&-\frac{1}{4}&\frac{1}{8}\\\frac{1}{4}&-1&\frac{3}{4}\\0&0&1\end{array}\right][/tex]

Inputing matrices and calculating their inverses depends on the model of a calculator you are using. You can refer to the user's manual on how to do that.

f. Our matrix equation has the following general form:

AX=B

where:

A=Coefficient matrix

X=Variables matrix

B= Answers matrix

In order to solve this type of equations, we can make use of the inverse of the coefficient matrix to end up with an equation that looks like this:

[tex]X=A^{-1}B[/tex]

Be careful with the order in which you are doing the multiplication, if A and B change places, then the multiplication will not work and you will not get the answer you need. So when solving this equation we get:

[tex]\left[\begin{array}{c}A\\B\\C\end{array}\right]=\left[\begin{array}{ccc}\frac{1}{8}&-\frac{1}{4}&\frac{1}{8}\\\frac{1}{4}&-1&\frac{3}{4}\\0&0&1\end{array}\right]*\left[\begin{array}{c}1\\\frac{47}{50}\\1\end{array}\right][/tex]

(Notice that I changed 0.94 for the fraction 47/50 you can get this number by dividing 94/100 and simplifying the fraction)

So, in order to do the multiplication, we need to multiply each row of the coefficient matrix by the answer matrix and add the results. Like this:

[tex]\frac{1}{8}*1+(-\frac{1}{4})(\frac{47}{50})+\frac{1}{8}*1[/tex]

[tex]\frac{1}{8}-\frac{47}{200}+\frac{1}{8}=\frac{3}{200}[/tex]

So the first number for the answer matrix is [tex]\frac{3}{200}[/tex]

[tex]\frac{1}{4}*1+(-1)(\frac{47}{50})+\frac{3}{4}*1[/tex]

[tex]\frac{1}{4}-\frac{47}{50}+\frac{3}{4}=\frac{3}{50}[/tex]

So the second number for the answer matrix is [tex]\frac{3}{50}[/tex]

[tex]0*1+0(\frac{47}{50})+1*1[/tex]

[tex]0+0+1=1[/tex]

So the third number for the answer matrix is 1

In the end, the matrix equation has the following answer.

[tex]\left[\begin{array}{c}A\\B\\C\end{array}\right]=\left[\begin{array}{c}\frac{3}{200}\\\frac{3}{50}\\1\end{array}\right][/tex]

which means that:

[tex]A=\frac{3}{200}[/tex]

[tex]B=\frac{3}{50}[/tex]

and C=1

so, when substituting these answers in the general form of the equation of the parabola we get:

[tex]Ax^{2}+Bx+C=y[/tex]

[tex]\frac{3}{200}x^{2}+\frac{3}{50}x+1=y[/tex]

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