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Answer:

-1.683

Step-by-step explanation:

Given :

Group 1 :

x1 = 667 ; n1 = 10 ; s1 = 20

Group 2 :

x2 = 679 ; n2 = 14 ; s2 = 15

The test statistic assuming equal variance :

x1 - x2 / √[Sp² * (1/n1 + 1/n2)]

sp² = [(n1 - 1)*s1² + (n2 - 1)*s2²] ÷ (n1 + n2 - 2)

Sp² = [(10 - 1)*20² + (14 - 1)*15²] = 296.59

Test statistic =

(667 - 679)/ √[296.59 * (1/10 + 1/14)]

-12 / 7.1304978

Test statistic = - 1.682

hope it helps

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Answer:

[tex][1, -4 ,5][/tex]

Step-by-step explanation:

In this question we are multiplying together two matrices. When we multiply a (1 x 3) matrix with a (3 x 3) matrix, we get a (1 x 3) matrix.

To compute each value, all you need to do is take the each value in each row in the first matrix, and multiply it by each value in each column of the second matrix and add up the result. So let's do that.

[tex]a = (2 * 1) + (1 * -1) + (0 * 0) = 2 - 1 + 0 = 1[/tex]

[tex]b = (2 * -1) + (1 * -2) + (0 * 1) = -2 -2 = -4[/tex]

[tex]c = (2 * 2) + (1 * 1) + (0 * 1) = 4 + 1 + 0 = 5[/tex]

Answer:

The guy above me is correct

Step-by-step explanation:

2022

Answer:

number of seeds planted per square foot

Step-by-step explanation:

response is the yield explained by how many seeds are planted

Answer:

Mr. Rowley=16:14

=8:7

Ms.Rivera= 64:60

=16:15

Answer:

0.0015 = 0.15% probability that if the motel books 150 guests, not enough seats will be available.

Step-by-step explanation:

Binomial probability distribution

Probability of exactly x successes on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

The standard deviation of the binomial distribution is:

[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]

Normal probability distribution

Problems of normally distributed distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex], if [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex].

150 guests booked:

This means that [tex]n = 150[/tex]

85% of booked guests show up for their room.

This means that [tex]p = 0.85[/tex]

Is the normal approximation suitable:

[tex]np = 150(0.85) = 127.5[/tex]

[tex]n(1-p) = 150(0.15) = 22.5[/tex]

Both greater than 10, so yes.

Mean and standard deviation:

[tex]\mu = E(X) = np = 150*0.85 = 127.5[/tex]

[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{150*0.85*0.15} = 4.3732[/tex]

Find the probability that if the motel books 150 guests, not enough seats will be available.

More than 140 show up, which, using continuity correction, is [tex]P(X > 140 + 0.5) = P(X > 140.5)[/tex], which is 1 subtracted by the p-value of Z when X = 140.5. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{140.5 - 127.5}{4.3732}[/tex]

[tex]Z = 2.97[/tex]

[tex]Z = 2.97[/tex] has a p-value of 0.9985.

1 - 0.9985 = 0.0015.

0.0015 = 0.15% probability that if the motel books 150 guests, not enough seats will be available.

Answer:

A majority of the data will lie between 38 and 46.

Step-by-step explanation:

It can be said that a majority of the data of a distribution lies within 1 standard deviation of the mean.

In this question:

Mean of 42, standard deviation of 4.

42 - 4 = 38

42 + 4 = 46

A majority of the data will lie between 38 and 46.

Given:

If x, y, and z are positive integers, then

[tex]2^x\times 3^y\times 5^z=54000[/tex]

To find:

The value of [tex]x+y+z[/tex].

Solution:

First we need to find the prime factors of 54000.

[tex]54000=2\times 2\times 2\times 2\times 3\times 3\times 3\times 5\times 5\times 5[/tex]

[tex]54000=2^4\times 3^3\times 5^3[/tex]        ...(i)

We have,

[tex]54000=2^x\times 3^y\times 5^z[/tex]        ...(ii)

On comparing (i) and (ii), we get [tex]x=4,y=3,z=3[/tex].

The sum of [tex]x,y,z[/tex] is:

[tex]x+y+z=4+3+3[/tex]

[tex]x+y+z=10[/tex]

Therefore, the value of [tex]x+y+z[/tex] is 10.

Answer:

B half the circumference or pi r

Step-by-step explanation:

The base of the parallelogram is pi r

To form the parallelogram the triangles are  removed from the bottom half of the circle and moved to flip the gaps in the top half.

Answer:C

Step-by-step explanation:

Answer: use photo. math

Step-by-step explanation:

boom

Answer:

52.25 - 1.50 = 50.75

Step-by-step explanation:

I'd recommend using a calculator or pencil and paper

53.25

-  1.50

--------

50.75

Answer:

7x is monomial according to question.

Answer:

Quadrant 2

Step-by-step explanation:

Given

[tex]\theta = 115^o[/tex]

Required

The quadrant

We have:

[tex]0^o < \theta < 90^o[/tex] --- quadrant 1

[tex]90^o < \theta < 180^o[/tex] --- quadrant 2

[tex]180^o < \theta < 270^o[/tex] --- quadrant 3

[tex]270^o < \theta < 360^o[/tex] --- quadrant 4

So, by comparison; we have:

[tex]90^o < \theta < 180^o[/tex]

Substitute 115 for [tex]\theta[/tex]

[tex]90^o < 115 < 180^o[/tex]

The above is true for quadrant 2

Answer:

31/10,32/10,33/10,34/10,35/10

Step-by-step explanation:

a rational number is formed when any two integers p and q are expressed in the form of p/q

to find two two sets of rational numbers BETWEEN any two numbers

a and b we need to express a and b and rational numbers....let us express 3and4 as rational numbers 3=30/10 4=40/10

the list of rational numbers between 3and4,that is, 30/10,31/10,32/10,33/10,34/10,35/10,36/10,37/10,38/10,39/10,40/10.

therefore the five rational numbers between 3 and 4 are (31/10,32/10,33/10,34/10,35/10...

I hope that helps

Answer:

75.03

Step-by-step explanation:

14×11×sin(77)

= 75.02649499..

≈ 75.03 (rounded to nearest hundredth)

Answered by GAUTHMATH

Answer:

Since we know the dot product of unit vectors, we can simplify the dot product formula to a⋅b=a1b1+a2b2+a3b3. we can use the same formula, but with a3=b3=0, a⋅b=a1b1+a2b2.

Step-by-step explanation:

Answer:

When time is short and you just want a rough estimate of the standard deviation, turn to the range rule to quickly estimate the standard deviation value. The standard deviation is approximately equal to the range of the data divided by 4. That's it, simple.

Answer:

k=4

Step-by-step explanation:

remove x:

10x.(-3) + ky.(-3)=-8.(-3)         (1)

-15x.2 - 6y.2 = 12.2               (2)

(1) - (2)  => -3ky+12y = 0

<=> (12-3k)y = 0

so that y has infinitely many solutions then

12-3k = 0 => k=4

Answer:

D. [tex]3x\sqrt{2x}[/tex]

Step-by-step explanation:

The problem gives on the following equation:

[tex]\sqrt{32x^3}+-\sqrt{16x^3}+4\sqrt{x^3}-2\sqrt{x^3}[/tex]

Alongside the information that ([tex]x\geq0[/tex]).

One must bear in mind that the operation ([tex]\sqrt[/tex]) indicates that one has to find the number that when multiplied by itself will yield the number underneath the radical. The easiest way to find such a number is to factor the term underneath the radical. Rewrite the terms under the radical as the product of prime numbers,

[tex]\sqrt{2*2*2*2*2*x*x*x}-\sqrt{2*2*2*2*x*x*x}+4\sqrt{x*x*x}-\sqrt{2*x*x*x}[/tex]

Now remove the duplicate factors from underneath the radical,

[tex]2*2*x\sqrt{2x}-2*2*x\sqrt{x}+4x\sqrt{x}-2x\sqrt{x}[/tex]

Simplify,

[tex]4x\sqrt{2x}-4x\sqrt{x}+4x\sqrt{x}-x\sqrt{2x}[/tex]

[tex]3x\sqrt{2x}[/tex]

Answer:

13

Step-by-step explanation:

since n is 4 substitute it where there's n in the equation

3(4)+1

12+1

13

I hope this helps

Answer:

13

Step-by-step explanation:

so you start with the equation 3n+1

since you know n=4 then u put it in place of n making the equation 3*4+1

then you multiply and it's 12+1 which equals 13

Answer:

C

Step-by-step explanation:

Just trust

Answer:

C

Step-by-step explanation:

I did the assignment in edge and got it right.

Proof:

Answer:

The answer is "0.081"

Step-by-step explanation:

Dimes [tex]= 55[/tex]

Calculating total coins [tex]= (23+55+20+19) = 117[/tex]

P(for a dime) [tex]= \frac{55}{117}[/tex]

Calculating remaining coins [tex]= 116[/tex]

Nickels [tex]= 20[/tex]

P(for nickel draw in second) [tex]= \frac{20}{116}[/tex]

P(for a dime after that a nickel, without replacement)

[tex]= \frac{55}{117} \times \frac{20}{116} \\\\= \frac{1100}{13572} \\\\=0.081[/tex]

Answer:

Step-by-step explanation:

Need the diagram for reference in order to answer...........

The first three terms of the Arithmetic Progression are 12, 17 and 22.

For an ARITHMETIC PROGRESSION, AP ;

First term = a

Second term = a + d

Third term = a + 2d

Where, d = common difference ;

If third term exceeds smallest by 10 ;

Third term - first term

a + 2d - a = 10

2d = 10

d = 10/2

d = 5

Sum of the three terms :

a + (a + d) + a + 2d = 51

3a + 3d = 51

d = 5

3a + 3(5) = 51

3a + 15 = 51

3a = 51 - 15

3a = 36

a = 12

The AP would be:

First term, a = 12

Second term, a + d = 12 + 5 = 17

Third term = a + 2(d) = 12 + 10 = 22

Therefore , the first three terms of the AP are :

12, 17 and 22

Learn more about ARITHMETIC PROGRESSION :

https://brainly.com/question/12006170

Answer:

The probability tree is;

                            0.95        [tex](+)[/tex]

                   [tex](S)[/tex]

          0.1              0.05        [tex](-)[/tex]

[  P  ]

          0.9             0.15          [tex](+)[/tex]                                                        

                  [tex](S_{no})[/tex]    

                             0.85         [tex](-)[/tex]        

Step-by-step explanation:

Given the data in the question;

10% of the rugby team members use steroids

so Probability of using steroid; P( use steroid ) = 10% = 0.10

Probability of not using steroid; P( no steroid use ) = 1 - 0.10 = 0.90

Since the test show positive for an athlete who uses steroids, 95% of the time.

Probability of using steroids and testing positive = 95% = 0.95

Probability of using steroids and testing Negative = 1 - 0.95 = 0.05

Also from the test, 15% of all steroid-free individuals also test positive.

so

Probability of not using steroids and testing positive = 15% = 0.15

Probability of not using steroids and testing negative = 1 - 0.15 = 0.85

To set up the probability tree, Let;

[tex](S)[/tex] represent steroid use

[tex](S_{no})[/tex] represent no steroid use

[tex](+)[/tex] represent test positive

[tex](-)[/tex] represent test negative

so we have;

                            0.95        [tex](+)[/tex]

                   [tex](S)[/tex]

          0.1              0.05        [tex](-)[/tex]

[  P  ]

          0.9             0.15          [tex](+)[/tex]                                                        

                  [tex](S_{no})[/tex]    

                             0.85         [tex](-)[/tex]        

Answer:

There are 32 nickels and 23 dimes.

Step-by-step explanation:

Lets say x is nickels and y is dimes

The first equation would be 55 = x + y

The second equation would be .05x + .10y = 3.90

The Solving Part:

Move y to the other side: x = 55 - y

Substitute x in the second equation: .05(55-y) + .10y = 3.90

Distribute, rearrange, and combine like terms: .05y = 1.15

Solve for y: Y = 23

Plug in 23 for y and solve: 55 - y = x ; 55 - 23 = x ; 55 - 23 = 32

x = 32

y = 23

32 nickels and 23 dimes

Answer:

There are 32 nickels and 23 dimes.

Step-by-step explanation:

Yay :) we solved the problem together :)))))

Answer:

y = -3 (you have to draw an horizontal line that passes for the point (0,-3)

Step-by-step explanation:

We have to find the middle points of the segments that unite the corrispettive points.

We are lucky because the images of the points have the same x coordinate of the original ones, so we have just to find the y coordinates.

Segment CC‘

(y1 + y2)/2 = (-1-5)/2 = -3

Segment AA’

(0-6)/2 = -3

Segmet BB’

(1-7)/2 = -3

Segment DD’

(1-7)/2 = -3

In conclusion we can say that the points of the reflection have all the y coordinate equal to -3.

the line is horizontal and its equation is : y = -3

Answer:

[tex]-8-6i[/tex]

Step-by-step explanation:

[tex]\frac{2-36i}{2+3i} * \frac{2-3 i}{2-3i}[/tex]

-104-78i /13

-8-6i

The square root of (2-36i)/(2+3i)​ is √(112-66i)/13.

The given expression is [tex]\frac{2-36i}{2+3i}[/tex].

The square root of a number is the inverse operation of squaring a number. The square of a number is the value that is obtained when we multiply the number by itself, while the square root of a number is obtained by finding a number that when squared gives the original number.

Multiply both numerator and denominator by 2-3i.

Now, [tex]\frac{2-36i}{2+3i}\times\frac{2-3i}{2-3i}[/tex]

= [tex]\frac{(2-36i)(2-3i)}{(2+3i)(2-3i)}[/tex]

= [tex]\frac{(4-72i+6i-108i^2)}{4-9i^2}[/tex]

= [tex]\frac{(4-66i+108)}{4+9}[/tex]

= [tex]\frac{(112-66i)}{13}[/tex]

Now square root is √(112-66i)/13

Therefore, the square root of (2-36i)/(2+3i)​ is √(112-66i)/13.

To learn more about the square root of a number visit:

https://brainly.com/question/8971086.

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