The average weekly assignment score of students in a statistics class is 7 out of 10 points. The professor proposes new incentives to boost the score of the students (like providing internship contacts etc.) He hopes that the results of running this incentives plan for a trial during the next couple of weeks will enable him to conclude that the incentives he offers increase the average weekly assignment score of students. What is the null hypothesis.
A. The average weekly score is strictly more than or equal to 7.
B. The average weekly score is less than our equal to 7.
C. The average weekly score is strictly less than 7.
D. The average weekly score is strictly more than 7.

The locus of the midpoints of all chords that can be drawn from a given fixed point [tex](a,b)[/tex] on a circle with a radius of 6 units, is a circle of radius 3 units with center at a point whose x & y coordinates are shifted from the center of the given circle by [tex]\frac{a}{2}[/tex] and [tex]\frac{b}{2}[/tex] respectively.

Given: A circle of radius 6 units

To find: The locus of the midpoint of all chords that can be drawn from a given point on the circle.

To find the required locus, we need to know the following:

Let, without loss of generality, the given circle be centered at the origin. Even if it is not, we can shift the origin to the center of the given circle with coordinate transformation.

Then, the equation of the given circle is [tex]x^{2}+y^{2} =6^{2}[/tex], that is, [tex]x^{2}+y^{2} = 36[/tex]

Let the coordinates of the given fixed point be [tex](a,b)[/tex]

Let the coordinates of any point on the circle be [tex](p,q)[/tex] and let the coordinates of the midpoint of the chord joining the points [tex](a,b)[/tex] and [tex](p,q)[/tex] be [tex](h,k)[/tex]

We have to find the locus of [tex](h,k)[/tex]

Then, using the midpoint formula,

[tex](h,k)=(\frac{a+p}{2} ,\frac{b+q}{2})[/tex]

On solving, we get,

[tex]p=2h-a,q=2k-b[/tex]

Since [tex](a,b)[/tex] and [tex](p,q)[/tex] are both points on the given circle, they satisfy the equation of the circle, [tex]x^{2}+y^{2} = 36[/tex]

Then,

[tex]a^{2} +b^{2} =36[/tex]

[tex]p^{2} +q^{2} =36[/tex]

Substituting [tex]p=2h-a,q=2k-b[/tex] in [tex]p^{2} +q^{2} =36[/tex], we have,

[tex](2h-a)^{2} +(2k-b)^{2} =36[/tex]

[tex](2(h-\frac{a}{2}) )^{2} +(2(k-\frac{b}{2}))^{2} =36[/tex]

[tex]4(h-\frac{a}{2})^{2} +4(k-\frac{b}{2})^{2} =36[/tex]

[tex](h-\frac{a}{2})^{2} +(k-\frac{b}{2})^{2} =\frac{36}{4}[/tex]

[tex](h-\frac{a}{2})^{2} +(k-\frac{b}{2})^{2} =9[/tex]

[tex](h-\frac{a}{2})^{2} +(k-\frac{b}{2})^{2} =3^{2}[/tex]

This is the locus of the point [tex](h,k)[/tex]

Replace [tex](h,k)=(x,y)[/tex] to get,

[tex](x-\frac{a}{2})^{2} +(y-\frac{b}{2})^{2} =3^{2}[/tex]

This is the equation of a circle with center at [tex](\frac{a}{2} ,\frac{b}{2} )[/tex] and radius 3 units.

Thus, we can conclude that the locus of the midpoints of all chords that can be drawn from a given fixed point [tex](a,b)[/tex] on a circle with a radius of 6 units, is a circle of radius 3 units with center at a point whose x & y coordinates are shifted from the center of the given circle by [tex]\frac{a}{2}[/tex] and [tex]\frac{b}{2}[/tex] respectively.

Learn more about locus here:

https://brainly.com/question/23824483

Answer:

c. 3 1/3

Step-by-step explanation:

8x-2-5x=8

3x=10

x=10/3=3 1/3

Answer:

x=[tex]3\frac{1}{3}[/tex]

Step-by-step explanation:

Hi there!

We want to find the value of x in this expression:

8x-2-5x=8

Our goal is to isolate x on one side

Combine like terms on the left side (add the terms with x together)

3x-2=8

Add 2 to both sides (-2+2=0)

3x-2=8

   +2  +2

__________

3x=10

Divide both sides by 3

x=[tex]\frac{10}{3}[/tex]

Simplify the improper fraction

x=[tex]3\frac{1}{3}[/tex]

Hope this helps!

Answer:

The leading coefficient is -8 as it is a mix of x and cardinal, if it was x alone then it wouldn't be the coefficient, we would use the next number shown.

If it was just a number and no x then it would still be the coefficient.

The degree is 9 as it is the highest power shown.

Step-by-step explanation:

See attachment for examples

Answer:

21

Step-by-step explanation:

All three sides are equal

2x-7 = x+y-9 = y+5

Using the last two

x+y-9 = y+5

Subtract y from each side

x+y-9-y = y+5-y

x-9 = 5

Add 9 to each side

x -9+9 = 5+9

x=14

We know the side length is

2x-7

2(14) -7

28-7

21

The side length is 21

Answer:

A, C, E, G

Step-by-step explanation:

Basic set operation

Answer:

the nullity of a matrix A is the demision of its null space:nullity A = dim (n(A).

Answer:

Total distance covered= 910 miles

Step-by-step explanation:

Distance = speed x time

Distance covered from home to airport = 70 x 3= 210 miles

Distance covered from airport to destination= 350 x 2= 700 miles

Add them together to get the final answer.

Hi there!  

»»————-　★　————-««

I believe your answer is:  

1 (15/16)

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\boxed{\text{Converting the Fractions...}}\\\\\rightarrow \frac{1}{2}=\frac{1*8}{2*8}= \boxed{\frac{8}{16}}\\\\\text{We would only compare the fractions because we have the same whole number.}\\\\\frac{8}{16} <\frac{15}{16}\\\\\text{Therefore:}\\\\\boxed{1\frac{15}{16} >1\frac{1}{2}}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

[tex]\\ \rm\longmapsto cot40=\dfrac{7.6}{EF}[/tex]

[tex]\\ \rm\longmapsto EF=\dfrac{7.6}{cot40}[/tex]

[tex]\\ \rm\longmapsto EF=\dfrac{7.6}{1.19}[/tex]

[tex]\\ \rm\longmapsto EF=6.38units[/tex]

Answer:

[tex]\displaystyle 6,38\:units[/tex]

Step-by-step explanation:

You would set your proportion up like so:

[tex]\displaystyle \frac{7,6}{EF} = cot\:40° \\ \\ 7,6 = EFcot\:40° → 6,3771571969... = \frac{7,6}{cot\:40°} \\ \\ 6,38 ≈ EF[/tex]

I am joyous to assist you at any time.

Answer:

v-(-5)<-9

v- remove brackets -5

v- -5= -4 +5 ( opposite operation)

v- = -4

v< -4

Answer:  Choice B

Explanation:

Everywhere you see an x, replace it with a+2.

[tex]f(x) = 3(x+5)+\frac{4}{x}\\\\f(a+2) = 3(a+2+5)+\frac{4}{a+2}\\\\f(a+2) = 3(a+7)+\frac{4}{a+2}\\\\[/tex]

Answer:

6+7=13

13+8=21

32+21=52

11+34=46

31+03=34

Step-by-step explanation:

im not sure in the 31+03

Answer:

Option B

Answered by GAUTHMATH

Answer:

28 units²

Step-by-step explanation:

Area of trapezoid =

2(8 + 4)/2 = 12

Area of rectangle =

2 x 8 = 16

16 + 12 = 28

If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

Part (a)

Locate x = -1 on the x axis. Draw a vertical line through this x value until you reach the f(x) curve. Then move horizontally until you reach the y axis. You should arrive at y = 4. Check out the diagram below to see what I mean.

Since f(-1) = 4, this means we can then say

g( f(-1) ) = g( 4 ) = 4

To evaluate g(4), we'll follow the same idea as what we did with f(x). However, we'll start at x = 4 and draw a vertical line until we reach the g(x) curve this time.

==========================================================

Part (b)

We use the same idea as part (a)

f(-2) = 5

g( f(-2) ) = g(5) = 6

==========================================================

Part (c)

Same idea as the last two parts. We start on the inside and work toward the outside. Keep in mind that g(x) is now the inner function for this part and for part (d) as well.

g(1) = -2

f( g(1) ) = f(-2) = 5

==========================================================

Part (d)

Same idea as part (c)

g(2) = 0

f( g(2) ) = f( 0 ) = 3

Answer:

7/12

Step-by-step explanation:

total: 12 roses

white roses: 5

pink roses: 7

fraction of pink roses = 7/12

Answer:

2.31 m

Step-by-step explanation:

with marking down to centimeter length, one can only estimate accurately to the nearest  centimeter or hundredth of a meter.

Answer:2.31 meter

Step-by-step explanation: none

Answer:

Player A has a probability 2/3 of making each of her shots, then she has a probability 1/3 of missing each shot.

Player B has a probability 1/2 of making each of his shots, then he also has a probability 1/2 of missing each shot.

Let's separate each case.

Let's define:

P(x) = probability of winning at the "x" shot.

Player A wins on the first shot.

Because she has a probability 2/3 of making each of her shots, the probability of winning at the first shot is

P(1) = 2/3

Now let's see the next case, player A wins at her second shot.

This means that first, she misses her first shot, with a probability of:

p₁ = 1/3

Player B must miss his shot, the probability is:

p₂ = 1/2

Now player A must make her shot, so the probability is:

p₃ = 2/3

The joint probability is the product of the individual probabilities, so we have:

P(2) = (1/3)*(1/2)*(2/3) = 1/9

Now we can see the pattern, for P(3) we have

A misses: p₁ = 1/3    (first shot of A)

B misses: p₂ = 1/2

A misses: p₃ = 1/3   (Second shot of A)

B misses: p₄ = 1/2

A makes the shot: p₅ = 2/3

P(3) =  (1/3)*(1/2)*(1/3)*(1/2)*(2/3) = 1/54

We already can see the pattern.

P(n) = (1/3)^(n - 1)*(1/2)*(n - 1)*(2/3)

Player A has a probability P of winning, and we can write P as:

P = P(1) + P(2) + P(3) + ...

Then we will have:

P = 2/3 + 1/9 + 1/54 + 1/324 + ... ≈ 0.8

Answer:

Point E.

.................

Answer:

Step-by-step explanation:

factor each total

27 = 3 x 3 x 3

18 = 3 x 3 x 2

45 = 3 x 3 x 5

The largest (and only) common factor is 3

however each factorization also contains the product 3 x 3 = 9

so the maximum each bag may have cost is $9 and if so, she sold 5 bags of sugar cookies.

another option would be that each bag cost $3 and she sold 15 bags of sugar cookies. However, the question asked for the maximum possible price.

Answer:

Remember that for a circle centered in the point (a, b) and with a radius R, the equation is:

(x - a)^2 + (y - b)^2 = R^2

Here we know that the submarine is located at the point (0, 0)

And the radar range has the equation:

2*x^2 + 2*y^2 = 128

You can see that this seems like a circle equation.

If we divide both sides by 2, we get:

x^2 + y^2 = 128/2

x^2 + y^2 = 64 = 8^2

This is the equation for a circle centered in the point (0, 0) (which is the position of the submarine) of radius R = 8 units.

The graph can be seen below, this is just a circle of radius 8.

We also want to see if the submarine's radar can detect a ship located in the point (6, 6)

In the graph, this point is graphed, and you can see that it is outside the circle.

This means that it is outside the range of the radar, thus the radar can not detect the ship.

Answer:

Lacy is 13 and Jack is 52

Step-by-step explanation:

In 3 years their ages will add up to 71 so you have to subtract 6 as there are two of them to get 65. Lacy's age is represented by x and since Jack is 4 times older his age is represented by 4x. So added together their age is 5x. So 5x=65. Then 65/5=13. So 13=x. So Lacy is 13 and Jack is 52 as 13x4 is 52.

Let breadth be x

We know

[tex]\boxed{\sf Area_{(Rectangle)}=Length\times Breadth}[/tex]

[tex]\\ \sf\longmapsto x(x+4)=22[/tex]

[tex]\\ \sf\longmapsto x^2+4x=22[/tex]

[tex]\\ \sf\longmapsto x^2+4x-22=0[/tex]

[tex]\\ \sf\longmapsto x=-2\pm\sqrt{26}[/tex]

It doesnot have any real roots

Answer:

1320 m^2

Step-by-step explanation:

area of ground = π r ^2

= (22/7) × (137/2)^2

= 14,747.0714286 m^2

area of ground and path

=( 22/7)(143/2)^2

= 16,067.0714286 m^2

area of path

=16,067.0714286 -14,747.0714286

= 1320 m^2

note :

r = radius = diameter /2

area of a circle = π r^2

diameter of circle created with path and ground = 137 + 2 × width of path

= 137 + 2× 3 = 143 m

Answer:

Step-by-step explanation:

hol sinaoteentnedbieinlrpeagntaaau

Answer:

y=3x+1

Step-by-step explanation:

Determine slope with two coordinates and use it in the formula

Answer:

The area of a triangle is:

Area = 1/2(bh)

Area = 1/2(70)

Area = 35 square inches

Let me know  if this helps!

Answer:

-6

Step-by-step explanation:

a1= -3

r= -(3/2)/-3 = 0.5

r>-3

s= a1/1-r

= -3/1-0.5

=-6