100 POINTS

PLEASE PROVIDE STEPS.

THANK YOU!!!

Answer:

a) The range of scores that includes the middle 95% of these test scores is between 470 and 674.

b) The range of scores that includes the middle 90% of these test scores is between 488.1 and 655.9.

Step-by-step explanation:

68-95-99.7 rule:

The Empirical Rule states that, for a normally distributed random variable:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviation of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Z-score:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.

In this question:

Mean [tex]\mu = 572[/tex], standard deviation [tex]\sigma = 51[/tex]

a. Use the 68-95-99.7 rule to estimate the range of scores that includes the middle 95% of these test scores.

By the 68-95-99.7 rule, within 2 standard deviations of the mean.

572 - 2*51 = 470

572 + 2*51 = 674

The range of scores that includes the middle 95% of these test scores is between 470 and 674.

b. Use technology to estimate the range of scores that includes the middle 90% of these test scores.

Using the z-score formula.

Between these following percentiles:

50 - (90/2) = 5th percentile

50 + (90/2) = 95th percentile.

5th percentile.

X when Z has a pvalue of 0.05. So when X when Z = -1.645.

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

[tex]-1.645 = \frac{X - 572}{51}[/tex]

[tex]X - 572 = -1.645*51[/tex]

[tex]X = 488.1[/tex]

95th percentile.

X when Z has a pvalue of 0.95. So when X when Z = 1.645.

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

[tex]1.645 = \frac{X - 572}{51}[/tex]

[tex]X - 572 = 1.645*51[/tex]

[tex]X = 655.9[/tex]

The range of scores that includes the middle 90% of these test scores is between 488.1 and 655.9.

Answer:

C

Step-by-step explanation:

I’m rusty with my math, so I’m not 100% sure this is correct. My best attempt.

(1,-5) & (3,-17)

1=1x, -5=1y, 3=2x, -17=2y

Formula is y2-y1/x2-x1

-17 - -5 = -12

3 - 1 =2

So -12/2 = -6

Formula for the line is

y-y1 = m (x-x1)

In this equation m=-6

Y - -5 = -6 ( x - 1 )

Answer:C

Step-by-step explanation:

Answer:

[tex]T_1= \dfrac{F_gcos \theta_2}{sin (\theta_1+\theta_2)}[/tex]

Step-by-step explanation:

From the free body diagram attached  below; we will see that

T₃ = Fg   ------ (1)

Thus; as the system is in equilibrium, the net force in the x and y direction shows to be zero

Then;

[tex]\sum F_x= 0 \to T_2 Cos \theta _2 - T_1 cos \theta _1[/tex]

[tex]T_2 Cos \theta _2 = T_1 cos \theta _1 \ \ \ \ \ - - - (2)[/tex]

Also;

[tex]\sum F_y =0 \to T_2sin \theta_2+T_1sin \theta_1 - T_3 = 0[/tex]

[tex]T_3 = T_2sin \theta_2+T_1sin \theta_1[/tex]   ---- (3)

From equation (2):

[tex]T_2 = \dfrac{T_1cos \theta_1}{cos \theta_2}[/tex]

Replacing the above value for  T₂  into equation 3; we have

[tex]T_3 = \dfrac{T_1cos \theta_1}{cos \theta_2}sin \theta_2+T_1sin \theta_1[/tex]

[tex]T_3 cos \theta_2 = {T_1cos \theta_1}{}sin \theta_2+T_1sin \theta_1 cos \theta_2[/tex]

[tex]T_3 cos \theta_2 = T_1(cos \theta_1 sin \theta_2+sin \theta_1 cos \theta_2)[/tex]  ---- (4)

Using trigonometric identity Sin (A+B) = SIn A cos B + Cos A sin B

So ; equation 4 can now be:

[tex]T_3 cos \theta_2 = T_1sin(\theta _1 + \theta_2)[/tex]  --- (5)

replacing equation (1) into  equation (5) ; we have:

[tex]F_g}cos \theta_2 =T_1 sin (\theta_1+\theta_2)[/tex]

Hence; the tension in the string is:

[tex]T_1= \dfrac{F_gcos \theta_2}{sin (\theta_1+\theta_2)}[/tex]

Answer:

the 2nd one

i am pretty sure

Step-by-step explanation:

Answer:

C. 1:27

Step-by-step explanation:

a²/b²=1/9 => a=1 and b=3

a³/b³=1³/3³=1/27

C. 1:27

I agree with the other answer. Here's another way to see why the answer is 1:27

The surface areas are in ratio 1:9. This means we could have one square that has area 1 and the larger square is area 9.

The smaller square has sides of 1 and the larger square has sides of 3 (square root both area values).

Now if we had a cube that has dimensions of 1 unit, then the volume is 1*1*1 = 1 cubic unit. If we had a larger cube with dimensions of 3 units, then the volume is 3^3 = 3*3*3 = 27 cubic units. We can fit 27 smaller 1x1x1 cubes into the larger 3x3x3 cube.

Answer:

V1  = Base x Height = 43 x 15 = 645 (mm3)

V2 = Base x Height = 12 x 7 = 84 (mm3)

Hope this helps!

:)

Answer:

1) 645 mm³

2) 84 cm³

Step-by-step explanation:

Volume of prism:

Base area × height

1) 43 × 15 = 645 mm³

2) 12 × 7 = 84 cm³

Answer:

0

Step-by-step explanation:

they are on the bed

The total legs on the floor excluding chicken is 50 legs

From the given question, the following animals have 4 legs

dogs, cats, girraffe and cows

Duck and chickens both have 2 legs

The total number of legs on the floor = 4(2) + 4(4) + 1(4) + 5(4) + 1(2)

Total number. = 8 + 20 + 22
Total number = 50legs

Hence the total legs on the floor excluding chicken is 50 legs

Learn more on word problems here:

https://brainly.com/question/13818690

#SPJ5

Answer:

Number of total bees = 400

Step-by-step explanation:

He catches 100 bees from the hive and marks each one with a dye.

He later catches 60 and 15 were marked with the dye.

Its very to estimate from the data given.

I'll answer it with ratio.

We'll ratio number of bees with dye to total he caught the second day.

I.e 15:60 = 1:4

We'll multiply this ratio with the number he caught the first day to know the total.

1/4x =100

X = 100*4

X= 400

Where x is the total number of bees in the bee hive.

Answer:

8.1 g/cm

Step-by-step explanation:

Answer: 64 yards I think

Step-by-step explanation:

Answer: If it's just 8 feet wide, 64 yards, if 8 and 1/2, 68 yards.

Step-by-step explanation:

Answer:

  5

Step-by-step explanation:

Solving the given equation for r, we get ...

  y = rx

  y/x = r

Then we can find r from any pair in the table:

  r = 35/7 = 5

The constant of proportionality is 5.

Answer:

y=3

Step-by-step explanation:

i did it in khan academy :)

Answer:Use Distributive property

Answer:

9

Step-by-step explanation:

Not sure if it is right, don't at me :)

Answer:nth term=a1 - 27n + 27

Step-by-step explanation:

first term =a1

common difference=d=-1-21

d=-27

Using the formula

Tn=a1 + d x (n-1)

nth term=a1 + (-27)(n-1)

nth term=a1 - 27n + 27

Answer:

[tex]\frac{-abx^{6}+1 }{b}[/tex]

Step-by-step explanation:

Answer:

number of Lola hats = h

number of Polly hats = 3h

number of Darla hats = 3h - 8

Step-by-step explanation:

Lola has h number of hats . Polly has triple as many as Lola . Then Darla has eight number of hat less than Polly. The expression for how many hat each person has in terms of h can be express below.

Let

number of Lola hats = h

number of Polly hats = 3h (recall Polly has triple as many as Lola)

number of Darla hats = 3h - 8(Note Darla has 8 number less of hats than Polly who already have 3h number of hats)

The simplest way to explain this is that Lola has h number of hats. This means she has h number of hats .Polly has triple of Lola hats, this implies that 3 times h of Lola hats is Polly hats.  Then finally Darla hats is 8 less than Polly hats. This simply means if you subtract 8 from Polly's hats you have gotten Darla's hats.

Answer:B.104 feet squared

Step-by-step explanation:

First find the area of the rectangle 11×10=110 then find the area of the window 3×2=6 then subtract 110-6=104

Answer:

B

Step-by-step explanation:

Answer:

9 meters every second

Step-by-step explanation:

45/5=9

5/5=1

9:1

Answer:

 |Z| = |-52.5|  = 52.5 > 1.96 at 0.05 level of significance

 Null  hypothesis is rejected

We rejected the researcher's claim

A researcher do not claims that 96% of college graduates say their college degree has been  a good investment.

Step-by-step explanation:

Explanation:-

Given data A researcher claims that 96% of college graduates say their college degree has  been a good investment.

Population proportion 'P' = 0.96

                                       Q = 1-P = 1- 0.96 = 0.04

In a random sample of 2000 graduates, 1500 say their college degree has

been a good investment.

Sample proportion

                       [tex]p^{-} = \frac{x}{n} = \frac{1500}{2000} = 0.75[/tex]

Level of significance  ∝ = 0.05

[tex]Z_{\frac{\alpha }{2} } = Z_{\frac{0.05}{2} } = Z_{0.025} = 1.96[/tex]

Test statistic

                        [tex]Z = \frac{p^{-} - P }{\sqrt{\frac{PQ}{n} } }[/tex]

                        [tex]Z = \frac{0.75 - 0.96 }{\sqrt{\frac{0.96 X 0.04}{2000} } }[/tex]

                        [tex]Z = \frac{-0.21}{0.00435} = -52.5[/tex]

    |Z| = |-52.5|  = 52.5 > 1.96 at 0.05 level of significance

  Null  hypothesis is rejected

  We rejected the researcher's claim

Conclusion:-

A researcher do not claims that 96% of college graduates say their college degree has been  a good investment.

Answer: m = -2.

The given equation is: [tex]\frac{m}{m+4}+\frac{4}{4-m}=\frac{m^{2}}{m^{2}-16}[/tex].

The LCM of the denominators = [tex]m^{2}-16=(m+4)(m-4)[/tex].

We multiply both sides by LCM.

[tex]\left(m+4\right)\left(m-4\right)\left(\frac{m}{m+4}+\frac{4}{4-m}\right)=\left(m+4\right)\left(m-4\right)\cdot\frac{m^{2}}{m^{2}-16}[/tex]

[tex]m\left(m-4\right)-4\left(m+4\right)=m^{2}[/tex]

[tex]m^{2}-4m-4m-16=m^{2}[/tex]

[tex]8m=-16\\m=-2[/tex]

Learn more: https://brainly.com/question/13769924

Answer:

M=-2 B

Step-by-step explanation:

trust me i took the quiz

Answer:

  -5

Step-by-step explanation:

If the second equation is multiplied by 4, the coefficient of the x-variable will be 5·4 = 20. To eliminate the x-variable by addition, the first equation needs to be multiplied by a value that will result in an x-coefficient of -20. If that value is k, then we have ...

  4k = -20

  k = -20/4 = -5

The first equation should be multiplied by -5 to eliminate the x-variable by addition.

_____

Comment on general case

In general, if you have ...

  ax +by = c

  dx +ey = f

to eliminate the x-variable by addition, you can multiply the second equation by "a" and the first equation by "-d". In the problem above, those numbers are 4 and -5.

Answer:

-5

Step-by-step explanation:

Answer:

we need a picture to help

Answer:

Keep the circle closed like it is and draw an incresing line (towards the positive numbers)(basically towards the right) with the arrow at the end of it

Step-by-step explanation:

Answer:

480 cm ^ 2

Step-by-step explanation:

To calculate the surface area of the figure, we must calculate the surface area of the cube, we know that they are identical, therefore, calculating the area of one is sufficient.

We have that the surface area of a cube is:

A = 6 * a ^ 2

where a is the edge, we know that if it is a cube all its sides are equal, in this case it is 4 centimeters, if we replace we have:

A = 6 * (4 ^ 2)

A = 96

96 square centimeters is the area of a cube, but since the area of the object would be the sum of the area of all the cubes, then:

AT = 96 * 5

AT = 480 cm ^ 2

The surface area of the object formed with the cubes is 480 cm ^ 2

Answer:

4

Step-by-step explanation:

We just have to find the corresponding d(t) value when t=2. From the graph, we can see that when t = 2, d(2) = 4. Hope this helps!

Step-by-step explanation:

[tex] {a}^{2} + {b}^{2} = {c}^{2} \\ {9}^{2} + {40}^{2} = {41}^{2} \\ 81 + 1600 = 1681 \\ 1681 = 1681[/tex]

Answer:

DUEDY A. 32 degrees

Step-by-step explanation:

PATROLLING WEE WOOO

Xd

Answer:

55  125

Step-by-step explanation:

Let the smaller angle = x

Let the larger angle = x + 70

They are supplementary so the total of the two angles, by definition must be 180 degrees. Note that you should understand that any number of angles can but supplementary as long as they all add up to 180 degrees.

x + x + 70 = 180

2x + 70 = 180

2x + 70 - 70 = 180 - 70

2x = 110

2x/2 = 110/2

x = 55

the smaller angle = 55 degrees

The larger angle = 55 + 70 = 125

Answer:

  D.  31

Step-by-step explanation:

The edge dimension of a cube is the cube root of the volume. For the two boxes that are 1331 m³, the height is ...

  ∛(1331 m³) = 11 m

For the box that is 729 m³, the height is ...

  ∛(729 m³) = 9 m

Then the total height of the stack of boxes is ...

  11 m + 11 m + 9 m = 31 m

Answer:

31

Step-by-step explanation:

I took the test on Edmentum, have a good day hope it helps :)

Answer:

B

Step-by-step explanation:

The total surface area of a cubical lunch box having each edge as 10 cm is 600 square centimeter. Therefore, option A is the correct answer.

The surface area of the cube all six faces of the cube are made up of squares of the same dimensions then the total surface area of the cube will be the surface area of one face added six times to itself. The formula to find the surface area of a cube is 6a², where a is edge.

Given that, the cubical lunch box having each edge as 10 cm.

Here, surface area = 6×10²

= 600 square centimeter

Therefore, option A is the correct answer.

Learn more about the surface area of a cube here:

brainly.com/question/23273671.

#SPJ2

Answer:

V =108 ft^3

Step-by-step explanation:

The volume is found by

V = Bh  where B is the area of the base

B = the area of the trapezoid

B = 1/2 (b1+b2)*h of the trapezoid

B = 1/2(4+6)*4 = 1/2(10)*4 = 20

Now we can find the volume

V = 20* 9

V =108 ft^3