Shari wrote the numbers from 1 to 16 on a card.
Next, she crossed out all the numbers which are factors of 80.
Then, she crossed out all the numbers which are multiples of 3.
How many numbers were not crossed out?​

Answer:

C

Step-by-step explanation:

I explained in my last answer but someone deleted it

Question:

The relationship between t and r is expressed by the equation 2t+3r+6 = 0. If r increases by 4, which of the following statements about t must be true?

Answer:

The value of t is reduced by 6 when the value of r is increased by 4

Step-by-step explanation:

Given

[tex]2t + 3r + 6 = 0[/tex]

Required

What happens when r is increased by 4

[tex]2t + 3r + 6 = 0[/tex] -------- Equation 1

Subtract 2t from both sides

[tex]2t + 3r + 6 - 2t = 0 - 2t[/tex]

[tex]3r + 6 = - 2t[/tex] --- Equation 2

When r is increased by 4, equation 1 becomes

[tex]2T + 3(r+4) + 6 = 0[/tex]

Note that the increment of r also affects the value of t; hence, the new value of t is represented by T

Open bracket

[tex]2T + 3r+12 + 6 = 0[/tex]

Rearrange

[tex]2T + 3r+6 +12 = 0[/tex]

Substitutr -2t for 3r + 6 [From equation 2]

[tex]2T -2t +12 = 0[/tex]

Make T the subject of formula

[tex]2T = 2t - 12[/tex]

Divide both sides by 2

[tex]\frac{2T}{2} = \frac{2t - 12}{2}[/tex]

[tex]T = t - 6[/tex]

This means that the value of t is reduced by 6 when the value of r is increased by 4

Answer:

1. CA=16,500+5,050x

2. CB=24,500+3,450x

3. CA(x=5)=CB(x=5)=41,750

If keeped 4 years, Model A is more economical.

4. 5 years

5. From month 49 to 61.

6. The cost of ownership of Model A increases more than Model B, as it is less gas efficient. The break-even point for x is reduced from x=5 to x=2.35.

7. The fixed cost are reduced by a 40%, so the variable cost, the ones that depend on time of ownership, are increased in importance.

Step-by-step explanation:

We can express the cost of ownership as the sum of the purchase cost, gas cost and insurance cost.

1. For model A we have:

[tex]\text{Cost of ownership}=\text{Purchase cost}+\text{Gas cost}+\text{Insurance cost}\\\\\text{Cost of ownership}=\$16,500+3 \dfrac{\$}{gal}\cdot\dfrac{1\,gal}{25\,miles}\cdot \dfrac{40,000\,miles}{year}\cdot x+\$250\cdot x\\\\\\\text{Cost of ownership}=\$16,500+\$4,800x+\$250x\\\\\\\text{Cost of ownership}=$16,500+\$5,050x[/tex]

2. For model B we have:

[tex]\text{Cost of ownership}=\text{Purchase cost}+\text{Gas cost}+\text{Insurance cost}\\\\\text{Cost of ownership}=\$24,500+3 \dfrac{\$}{gal}\cdot\dfrac{1\,gal}{40\,miles}\cdot \dfrac{40,000\,miles}{year}\cdot x+\$450\cdot x\\\\\\\text{Cost of ownership}=\$24,500+\$3,000x+\$450x\\\\\\\text{Cost of ownership}=$24,500+\$3,450x[/tex]

3. If x=5, the costs for each car are:

[tex]\text{CoOwn A}=16,500+5,050\cdot(5)=16,500+25,250=41,750\\\\\\\text{CoOwn B}=24,500+3,450\cdot(5)=24,500+17,250=41,750[/tex]

5 years is the break-even point for the cost of ownership between these two cars.

If you plan to keep the car for 4 years, the costs are:

[tex]\text{CoOwn A}=16,500+5,050\cdot(4)=16,500+20,200=36,700\\\\\\\text{CoOwn B}=24,500+3,450\cdot(4)=24,500+13,800=38,300[/tex]

For a 4 year period ownership, the model A is more economical ($36,700).

4. This happens for 1 year, the fifth year, in which the two models have the same cost of ownership.

5. At the 5th year, the cost for both models are the same.

Then, this corresponds to the months 4*12+1=48+1=49 and 5*12+1=61.

6. If the cost of gas doubles, the cost of ownership would rise for both model, but more for the Model A, which is less gas efficient and hence has a higher gas cost.

Model A

[tex]\text{Cost of ownership}=\text{Purchase cost}+\text{Gas cost}+\text{Insurance cost}\\\\\text{Cost of ownership}=\$16,500+6 \dfrac{\$}{gal}\cdot\dfrac{1\,gal}{25\,miles}\cdot \dfrac{40,000\,miles}{year}\cdot x+\$250\cdot x\\\\\\\text{Cost of ownership}=\$16,500+\$9,600x+\$250x\\\\\\\text{Cost of ownership}=$16,500+\$9,850x[/tex]

Model B

[tex]\text{Cost of ownership}=\text{Purchase cost}+\text{Gas cost}+\text{Insurance cost}\\\\\text{Cost of ownership}=\$24,500+6 \dfrac{\$}{gal}\cdot\dfrac{1\,gal}{40\,miles}\cdot \dfrac{40,000\,miles}{year}\cdot x+\$450\cdot x\\\\\\\text{Cost of ownership}=\$24,500+\$6,000x+\$450x\\\\\\\text{Cost of ownership}=$24,500+\$6,450x[/tex]

The breakeven point goes from x=5 (for $3 per gallon) to x=2.35 (for $6 per gallon).

[tex]16,500+9,850x=24,500+6,450x\\\\(9,850-6,450)x=24,500-16,500\\\\x=8,000/3400=2.35[/tex]

7. If we can sell any car for 40% of its value at any time, the cost of ownership becames:

Model A:

[tex]\text{Cost of ownership}=16,500+5,050x-0.4\cdot16,500\\\\\text{Cost of ownership}=9,900+5,050x[/tex]

Model B

[tex]\text{Cost of ownership}=24,500+3,450x-0.4\cdot24,500\\\\\text{Cost of ownership}=14,700+3,450x[/tex]

The fixed costs are lowered by 40%, so the variable costs (the ones that depend on time) became more important.

Answer: the value of the annuity when you retire is $130919

Step-by-step explanation:

We would apply the future value which is expressed as

FV = C × [{(1 + r)^n - 1}/r]

Where

C represents the yearly payments.

FV represents the amount of money

in your account at the end of 10 years.

r represents the annual rate.

n represents number of years or period.

From the information given,

r = 7% = 7/100 = 0.07

C = 20/100 × 47400 = $9480

n = 10 years

Therefore,

FV = 9480 × [{(1 + 0.07)^10 - 1}/0.07]

FV = 9480 × [{1.967 - 1}/0.07]

FV = 9480 × 13.81

FV = $130919

Answer:

20

Step-by-step explanation:

The simplified expression is -5x+21

-5(0.2)+21=

-1+21= 20

Answer:

24

Step-by-step explanation:

f(x)= (6−2x)+(15−3x)

x=-0.2

f(-0.2)=(6−2(-0.2)+(15−3(-0.2))

f(-0.2)=(6+0.4)+(15+0.6)

f(-0.2)=6.4+15.6

f(-0.2)=22

Answer:

a. $840

b. $1,260

Step-by-step explanation:

a. 2/5 x 2100 = 840

b. 2100 - 840 = 1,260

Step-by-step explanation:

Take the $50 and quit.

(Each game as outlined by drwls has an expected value of $1.50.

You are playing it 5 times, so the expected return is $7.50.

Your choice was to either accept $50 or play the game)

Answer:

$9

Step-by-step explanation:

Let the price of one order of wings be w.

Let the price for one order of soft drinks be s.

Three friends went to a restaurant and ordered two orders of wings and three soft drinks. Their bill totaled $22.50. This means that:

2w + 3s = 22.50 _____________(1)

Five friends went to the same restaurant and ordered three orders of wings and a soft drink each. Their bill totaled $34.50. This means that:

3w + 5s = 34.50 ______________(2)

We have a system of quadratic equations:

2w + 3s = 22.50 _____________(1)

3w + 5s = 34.50 ______________(2)

Multiply (1) by 5 and (2) by 3:

10w + 15s = 112.50 _______(3)

9w + 15s = 103.50 _______(4)

Subtract (4) from (3):

w = $9

Therefore, the price of one order of wings is $9.

Answer:

AC = 198

Step-by-step explanation:

Since all these points are collinear, we know that the addition of AB plus BC should give the same as AC. We can then set an equation that addresses this identity:

AB + BC = AC

5x +8 +6x - 1 = 12x - 11

Now re-arranging like terms in order to combine them:

8 - 1 + 11 = 12x - 5x - 6x

19 - 1  = 12x - 11x

18 = x

Now that we know the value of 'x", we can determine the value of AC:

AC = 12x - 11

AC = 12 (18) - 11

AC = 216 - 18

AC = 198

Answer:

Ok, for f(x) = x^2 we have only one x-intercept (actually, two equal x-intercepts) at x = 0.

Now, for g(x) = (x - 2)^2 - 3

First, let's analyze the transformations.

When we have g(x) = f(x - a) this means that we moved "a" units to the right (if a is positive)

When we have g(x) = f(x) + a, this means that (if a > 0) we move the graph "a" units up.

In this case we have both those transformations:

g(x) = f(x - 2) - 3

this means that we move 2 units to the right, and 3 units down (because the number is negative)

now we can find the roots of g(x) as:

g(x) = (x - 2)^2 - 3 = x^2 - 4x  + 4 - 3 = x^2 - 4x + 1 = 0

using the Bhaskara's equation:

[tex]x = \frac{4 +-\sqrt{4^2 - 4*1*1} }{2*1} = \frac{4 +- 3.5}{2}[/tex]

then the roots are:

x = (4 + 3.5)/2 = 3.75

x = (4 - 3.5)/2 = 0.25

Here we have two different x-intercepts

Answer:

Step-by-step explanation:

If n represents the number of nickels, and the number of quarters is 4 times the number of nickels, then the number of quarters is represented by 4n.

The total value of the coins in cents is ...

  5(n) +25(4n) = 210

  105n = 210 . . . . . . . . collect terms

  n = 210/105 = 2 . . . . number of nickels

  4n = 4(2) = 8 . . . . . . number of quarters

Peggy has 2 nickels and 8 quarters.

In the given point(-4,b) -4 is the x value.

Locate -4 on the graph and find the y value where the line is located. The y value would be b.

B = 1

Answer:

Step-by-step explanation:

x

2

+

4

x

+

3

x

2

+

4

x

+

3

Answer:

you forgot the rest of the question homie but once there is 20 companies both companies will be equal

Step-by-step explanation:

Answer:

20 windows

Step-by-step explanation:

Answer:

a. P(x≤9)=0.9999

b. P(x=6)=0.0430

c. P(x≥6)=0.0611

Step-by-step explanation:

The question is incomplete:

a.At most 9 will come to a complete stop?

b.Exactly 6 will come to a complete stop?

c.At least 6 will come to a complete stop?

d.How many of the next 20 drivers do you expect to come to a complete stop?

The amount of drivers from the sample that will come to a complete stop can be modeled by a binomial random variable with n=15 and p=0.2.

The probability that exactly k drivers from the sample come to a complete stop is:

[tex]P(x=k) = \dbinom{n}{k} p^{k}q^{n-k}[/tex]

a. We have to calculate the probability that at most 9 come to a complete stop:

[tex]P(x\leq9)=\sum_{k=0}^9P(x=k)\\\\\\P(x=0) = \dbinom{15}{0} p^{0}q^{15}=1*1*0.0352=0.0352\\\\\\P(x=1) = \dbinom{15}{1} p^{1}q^{14}=15*0.2*0.044=0.1319\\\\\\P(x=2) = \dbinom{15}{2} p^{2}q^{13}=105*0.04*0.055=0.2309\\\\\\P(x=3) = \dbinom{15}{3} p^{3}q^{12}=455*0.008*0.0687=0.2501\\\\\\P(x=4) = \dbinom{15}{4} p^{4}q^{11}=1365*0.0016*0.0859=0.1876\\\\\\P(x=5) = \dbinom{15}{5} p^{5}q^{10}=3003*0.0003*0.1074=0.1032\\\\\\P(x=6) = \dbinom{15}{6} p^{6}q^{9}=5005*0.0001*0.1342=0.043\\\\\\[/tex]

[tex]P(x=7) = \dbinom{15}{7} p^{7}q^{8}=6435*0*0.1678=0.0138\\\\\\P(x=8) = \dbinom{15}{8} p^{8}q^{7}=6435*0*0.2097=0.0035\\\\\\P(x=9) = \dbinom{15}{9} p^{9}q^{6}=5005*0*0.2621=0.0007\\\\\\P(x\leq9)=0.0352+0.1319+0.2309+0.2501+0.1876+0.1032+0.043+0.0138+0.0035+0.0007\\\\P(x\leq9)=0.9999[/tex]

b. We have to calculate the probability that exactly 6 will come to a complete stop:

[tex]P(x=6) = \dbinom{15}{6} p^{6}q^{9}=5005*0.0001*0.1342=0.043\\\\\\[/tex]

c. We have to calculate the probability that at least 6 will come to a complete stop:

[tex]P(x\geq6)=\sum_{k=6}^{15}P(x=k)\\\\\\P(x=6) = \dbinom{15}{6} p^{6}q^{9}=5005*0.0001*0.1342=0.043\\\\\\P(x=7) = \dbinom{15}{7} p^{7}q^{8}=6435*0*0.1678=0.0138\\\\\\P(x=8) = \dbinom{15}{8} p^{8}q^{7}=6435*0*0.2097=0.0035\\\\\\P(x=9) = \dbinom{15}{9} p^{9}q^{6}=5005*0*0.2621=0.0007\\\\\\P(x=10) = \dbinom{15}{10} p^{10}q^{5}=3003*0*0.3277=0.0001\\\\\\P(x=11) = \dbinom{15}{11} p^{11}q^{4}=1365*0*0.4096=0\\\\\\P(x=12) = \dbinom{15}{12} p^{12}q^{3}=455*0*0.512=0\\\\\\[/tex]

[tex]P(x=13) = \dbinom{15}{13} p^{13}q^{2}=105*0*0.64=0\\\\\\P(x=14) = \dbinom{15}{14} p^{14}q^{1}=15*0*0.8=0\\\\\\P(x=15) = \dbinom{15}{15} p^{15}q^{0}=1*0*1=0\\\\\\P(x\geq6)=0.043+0.0138+0.0035+0.0007+0.0001+0+0+0+0\\\\P(x\geq6)=0.0611[/tex]

Answer:

2 real solutions

Step-by-step explanation:

it is age heart rate and weather

Answer:

25

Step-by-step explanation:

I'm going with $25 since socks should cost as much as underwear, you wear them underneath and they're an essential.

Answer:

299.97 is the actual answer

Step-by-step explanation:

I took the test.

Answer:

Due to the fact that there is 21% chance of getting that many girls by chance and also In conjunction to that; there is no test involved as well , we can conclude that the method does not have statistical significance.

The result does not appear to have a practical significance.

Step-by-step explanation:

Given that:

In  a random selection 1936 users, we observed that the method gave birth to  950 boys and 986 girls

There is about a 21​% chance of getting that many girls if the method had no effect.

Due to the fact that there is 21% chance of getting that many girls by chance and also In conjunction to that; there is no test involved as well , we can conclude that the method does not have statistical significance.

Given that:

The number of girls = 986

Number of boys = 950

Number of babies born = 1936

The percentage of girls = number of girls born/ number of babies born

The percentage of girls = 986 /1936

The percentage of girls = 0.5093

The percentage of girls =  50.93%

We can infer that this method does not have a practical significance  because most couples would not prefer to use a method that raise the likelihood of a girl from the approximately 50% rate expected by chance to the 50.93% .

Answer:

226 cm^3

The mass of plastic used to make cylinder is greater

Step-by-step explanation:

Given:-

- The density of cone material, ρc = 1.4 g / cm^3

- The density of cylinder material, ρl = 0.8 g / cm^3

Solution:-

- To determine the volume of plastic that remains in the cylinder after gouging out a hemispherical amount of material.

- We will first consider a solid cylinder with length ( L = 10 cm ) and diameter ( d = 6 cm ). The volume of a cylinder is expressed as follows:

                                  [tex]V_L =\pi \frac{d^2}{4} * L[/tex]

- Determine the volume of complete cylindrical body as follows:

                                 [tex]V_L = \pi \frac{(6)^2}{4} * 10\\\\V_L = 90\pi cm^3\\[/tex]

- Where the volume of hemisphere with diameter ( d = 6 cm ) is given by:

                                 [tex]V_h = \frac{\pi }{12}*d^3[/tex]

- Determine the volume of hemisphere gouged out as follows:

                                 [tex]V_h = \frac{\pi }{12}*6^3\\\\V_h = 18\pi cm^3[/tex]

- Apply the principle of super-position and subtract the volume of hemisphere from the cylinder as follows to the nearest ( cm^3 ):

                               [tex]V = V_L - V_h\\\\V = 90\pi - 18\pi \\\\V = 226 cm^3[/tex]

Answer: The amount of volume that remains in the cylinder is 226 cm^3

- The volume of cone with base diameter ( d = 6 cm ) and height ( h = 5 cm ) is expressed as follows:

                               [tex]V_c = \frac{\pi }{12} *d^2 * h[/tex]

- Determine the volume of cone:

                              [tex]V_c = \frac{\pi }{12} *6^2 * 5\\\\V_c = 15\pi cm^3[/tex]

- The mass of plastic for the cylinder and the cone can be evaluated using their respective densities and volumes as follows:

                             [tex]m_i = p_i * V_i[/tex]

- The mass of plastic used to make the cylinder ( after removing hemispherical amount ) is:

                           [tex]m_L = p_L * V\\\\m_L = 0.8 * 226\\\\m_L = 180.8 g[/tex]

- Similarly the mass of plastic used to make the cone would be:

                           [tex]m_c = p_c * V_c\\\\m_c = 1.4 * 15\pi \\\\m_c = 65.973 g[/tex]

Answer: The total weight of the cylinder ( m_l = 180.8 g ) is greater than the total weight of the cone ( m_c = 66 g ).

The volume of the remaining plastic in the cylinder is large, which

makes the weight much larger than the weight of the cone.

Responses:

Density of the plastic for the cone = 1.4 g/cm³

Density of the plastic used for the cylinder = 0.8 g/cm³

From a similar question, we have;

Height of the cylinder = 10 cm

Diameter of the cylinder = 6 cm

Height of the cone = 5 cm

(a) Radius of the cylinder, r = 6 cm ÷ 2 = 3 cm

Volume of a cylinder = π·r²·h

Volume of a hemisphere = [tex]\mathbf{\frac{2}{3}}[/tex] × π×  r³

Volume of the cylinder after it has been hollowed out, V, is therefore;

Which gives;

[tex]V = \pi \times 3^2 \times 10 - \frac{2}{3} \times \pi \times 3^3 \approx \mathbf{ 226}[/tex]

(b) Volume of the cone = [tex]\mathbf{\frac{1}{3}}[/tex] × π × 3² × 5 ≈ 47.1

Mass of the cone = 47.1 cm³ × 1.4 g/cm³ ≈ 66 g

Mass of the hollowed cylinder ≈ 226 cm³ × 0.8 g/cm³ = 180.8 g

Learn more about volume and density of solids here:

https://brainly.com/question/4773953

Answer: [tex]2x^2+3x-2[/tex]

Step-by-step explanation:

You can do long division, which is very very hard to show with typing on a keyboard. You essentially want to divide the leading coefficient for each term. Ill try my best to explain it.

Do [tex]\frac{2x^3}{x}=2x^2[/tex]. Write 2x^2 down. Now multiply (x - 3) by it. Then subtract it from the trinomial.

[tex]2x^2*(x-3)=2x^3 -6x^2\\(2x^3 -3x^2-11x+6)-(2x^3-6x^2) = 3x^2-11x+6[/tex]

Now do [tex]\frac{3x^2}{x} =3x[/tex]. Write that down next to your 2x^2. Multiply 3x by (x - 3) to get:

[tex]3x(x-3)=3x^2-9x\\(3x^2-11x+6)-(3x^2-9x)=-2x+6[/tex]

Your final step is to do [tex]\frac{-2x}{x} =-2[/tex]. Write this -2 next to your other two parts

Multiply -2 by (x - 3) to get:

[tex]-2(x-3)=-2x+6\\(-2x+6)-(-2x+6)=0[/tex]

Our remainder is 0 so that means (x - 3) goes into that trinomial exactly:

[tex]2x^2+3x-2[/tex] times

Answer:

2x² + 3x -2

Step-by-step explanation:

2x³ - 3x² - 11x + 6 : (x - 3)

2x³ - 6x² from (x - 3) * 2x²

-------------------------- —

3x² - 11x + 6

3x² - 9x from (x - 3) * 3x

-------------------------- —

- 2x + 6

- 2x + 6 from (x - 3) * (-2)

-------------------------- —

0

so 2x³ - 3x² - 11x + 6 : (x - 3) = 2x² + 3x -2

Answer:

Step-by-step explanation:

For this kind of question you'd be better off if you'd write down and share your own answers to these conceptual questions and then ask for Brainly feedback on what you have written.  You'll need to understand the concept of "function" often in algebra and beyond.

What concepts (only the names) did you need to accommodate the concept of function in your mind?  input, output, rule, domain, range, mapping, variation (direct and inverse)

Simplest function:  y = c  (there's only one x-value and y equals that value)

In your day to day, is there any occurring fact that can be interpreted as a function?  An electronic parking meter:  the amount of time you can park at the meter without risking getting a ticket is dependent upon the number of quarters you insert into the meter, e. g, 15 minutes for 25 centers, 30 minutes for 50 cents, and so on.

Is it possible to view a function?  Sure.  Graph the function.

What strategy are you using to get the graph of a function?  Set up a coordinate plane.  Label the horizontal axis "x" and the vertical axis "y".  Choose x (input) values that are included in the domain of the function.  If the domain includes '0' you will be finding the 'y-intercept' of the function.  Write the input and output as a point:  (x, y).  Plot that point.  Choose other x values within the domain and calculate the corresponding y value for each.  Plot several more points and draw a line or a curve through them.  Of course there are more sophisticated strategies for graphing functions.  Remember:  If you're working with a function, there is never more than one output or y value for any particular input value.

Answer:

The length of the side opposite the 60 degree angle 'c' = 4

Step-by-step explanation:

Step(i):-

Given data ∠A = 90° , ∠B = 60° and ∠C = 30°

Given data the length of the side opposite the 30 degree angle is 8

let  'a' = 8

step(ii):-

By using sine rule formula in properties of triangle

[tex]\frac{a}{Sin A} = \frac{b}{Sin B} = \frac{c}{Sin C} = 2 R[/tex]

[tex]\frac{a}{Sin A} = \frac{c}{Sin C}[/tex]

[tex]\frac{8}{Sin 90} = \frac{c}{Sin 30}[/tex]

cross multiplication , we get

[tex]\frac{8 X sin 30}{Sin 90} = c[/tex]

we know that trigonometry formulas

sin 30° = [tex]\frac{1}{2}[/tex]   and sin 90°= 1

C =  8 X 1/2 = 4

conclusion:-

The length of the side opposite the 60 degree angle 'c' = 4

Answer:

Step-by-step explanation:

The question is incomplete. The missing data is:

30, 155, 205, 235, 180, 235, 70, 250, 135, 145, 225, 230, 30

Solution:

Mean = (30 + 155 + 205 + 235 + 180 + 235 + 70 + 250 + 135 + 145 + 225 + 230 + 30)/13 = 163.5

Standard deviation = √(summation(x - mean)²/n

n = 13

Summation(x - mean)² = (30 - 163.5)^2 + (155 - 163.5)^2 + (205 - 163.5)^2+ (235 - 163.5)^2 + (180 - 163.5)^2 + (235 - 163.5)^2 + (70 - 163.5)^2 + (250 - 163.5)^2 + (135 - 163.5)^2 + (145 - 163.5)^2 + (225 - 163.5)^2 + (230 - 163.5)^2 + (30 - 163.5)^2 = 73519.25

Standard deviation = √(73519.25/13) = 75.2

We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean

For the null hypothesis,

µ ≤ 150

For the alternative hypothesis,

µ > 150

It is a right tailed test.

a) Since the number of samples is small and no population standard deviation is given, the distribution is a student's t.

Since n = 13,

Degrees of freedom, df = n - 1 = 13 - 1 = 12

t = (x - µ)/(s/√n)

Where

x = sample mean = 163.5

µ = population mean = 150

s = samples standard deviation = 75.2

t = (163.5 - 150)/(75.2/√13) = 0.65

The lower the test statistic value, the higher the p value and the higher the possibility of accepting the null hypothesis.

b) We would determine the p value using the t test calculator. It becomes

p = 0.26

Since alpha, 0.05 < than the p value, 0.26, then we would fail to reject the null hypothesis. Therefore, At a 5% level of significance, the sample data does not show significant evidence that the mean number of friends for the student population at the college who use the social media website is larger than 150.

c)

1.The test statistic value is the difference between the sample mean and the null hypothesis value.

Answer:

[tex] (17.714-28.714) -2.681 \sqrt{\frac{4.461^2}{7} +\frac{7.387^2}{7}}= -19.745[/tex]

[tex] (17.714-28.714) +2.681 \sqrt{\frac{4.461^2}{7} +\frac{7.387^2}{7}}= -2.255[/tex]

Step-by-step explanation:

For this case we have the following info given:

Treatment: 12 13 15 19 20 21 24

Control: 18 23 24 30 32 35 39

We can find the sample mean and deviations with the the following formulas:

[tex] \bar X = \frac{\sum_{i=1}^n X_i}{n}[/tex]

[tex] s =\sqrt{\frac{\sum_{i=1}^n (X_i- \bar X)^2}{n-1}}[/tex]

And repaplacing we got:

[tex] \bar X_T = 17.714[/tex] the sample mean for treatment

[tex] \bar X_C = 28.714[/tex] the sample mean for treatment

[tex] s_T= 4.461[/tex] the sample deviation for treatment

[tex] s_C= 7.387[/tex] the sample deviation for control

[tex]n_T= n_C= 7[/tex] the sample size for each sample

The degrees of freedom are given by:

[tex] df= 7+7-2= 12[/tex]

The confidence interval for the difference of means is given by:

[tex] (\bar X_T -\bar X_C) \pm t_{\alpha/2} \sqrt{\frac{s^2_T}{n_T} +\frac{s^2_C}{n_C}}[/tex]

The confidence is 98% so then the significance is [tex]\alpha=0.02[/tex] and [tex] \alpha/2 =0.01[/tex]. Then the critical value would be:

[tex] t_{\alpha/2}=2.681[/tex]

And replacing we got:

[tex] (17.714-28.714) -2.681 \sqrt{\frac{4.461^2}{7} +\frac{7.387^2}{7}}= -19.745[/tex]

[tex] (17.714-28.714) +2.681 \sqrt{\frac{4.461^2}{7} +\frac{7.387^2}{7}}= -2.255[/tex]

Answer:

(a) 0.25

(b) 0.944

(c) 0.444

(d) 0.167

Step-by-step explanation:

There are six possible outcomes for each die, which means that the number of possible outcomes is:

[tex]n=6*6 = 36[/tex]

(a) In order for each die to show four or more spots they will both have to land on a four, five or six. The probability of this happening is:

[tex]P(A) = \frac{3*3}{36}=0.25[/tex]

(b) There are only two possible outcomes for which the sum is three (1 and 2, or 2 and 1). The probability of the sum NOT being three is:

[tex]P(B) = 1-\frac{2}{36}=0.944[/tex]

(c) If neither a one or a six must appear, then there are 4 possible outcomes for each die, the probability is:

[tex]P(C) = \frac{4*4}{36}=0.444[/tex]

(d) For each one of the six possible numbers on the first die, there is only one on the second die for which the sum of the spots is 7, totaling six possible ways to sum 7:

[tex]P(D) = \frac{6}{36}=0.167[/tex]

The required probability output from a throw of two six sided dice are as follows :

The sample space for two throw of a six-sided die :

Recall :

A.) Obtaining 4 or more spots :

Required spot = (5, 6, 7) on each die = 3 × 3 = 9 outcomes

P(4 or more spot) = 9/36 = 0.25

B.) Sum of spot is not 3 :

Sum of spot = 3 ; (1, 2) and (2, 1) = 2 possible outcomes

P(sum not 3) = 1 - (2/36) = 1 - 1/8 = 17/18 = 0.944

C.) neither a one nor 6 appears :

Required = (2, 3, 4, 5) = 4 × 4 = 16

P(neither 6 nor 1) = 16/36 = 4/9 = 0.44

D.) Sum of spot equals 7

Required = (1, 6),(6,1),(5,2),(2,5),(3,4),(4,3) = 6 outcomes

P(sum equals 7) = 6/36 = 1/6 = 0.167

Learn more :https://brainly.com/question/18405415

Answer:

63.45

Step-by-step explanation:

First, it should be noted that the question is incorrect because 64 can't be divided by 11 but assuming that the question is correct, the solution is as follows

Given

LCM = 368

HCF = 11

One number = 64

Required

The other number

Let both numbers be represented by m and n, such that

[tex]m = 64[/tex]

From laws of HCF and LCM

The product of both numbers = Product of HCF and LCM

i.e.

[tex]m * n = HCF * LCM[/tex]

By substituting 68 for m; 368 for LCM and 11 for HCF

[tex]m * n = HCF * LCM[/tex] becomes

[tex]64 * n = 368 * 11[/tex]

[tex]64n = 4048[/tex]

Divide both sides by 64

[tex]\frac{64n}{64} = \frac{4048}{64}[/tex]

[tex]n = \frac{4048}{64}[/tex]

[tex]n = 63.25[/tex]

Answer:

To be in the top 1% of the runners, the man has to run the 400 meters in at most 55.768 seconds.

Step-by-step explanation:

When the distribution is normal, we use 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, we have that:

[tex]\mu = 93, \sigma = 16[/tex]

How fast does a man have to run to be in the top 1% of runners?

The lower the time, the faster they are. So the man has to be at most in the 1st percentile, which is X when Z has a pvalue of 0.01. So he has to run in at most X seconds, and X is found when Z = -2.327. Then

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

[tex]-2.327 = \frac{X - 93}{16}[/tex]

[tex]X - 93 = -2.327*16[/tex]

[tex]X = 55.768[/tex]

To be in the top 1% of the runners, the man has to run the 400 meters in at most 55.768 seconds.