Please HELP!

How many pairs (A, B) are there where A and B are subsets of {1, 2, 3, 4, 5, 6, 7, 8} and A ∩ B has exactly two elements?

Answers

Answer 1

Answer:

There are 256 pairs in all.


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The graph of a line goes through the points (-4,3) and (6,8). What is the equation of the line in slope-intercept form?
Enter the correct answer in the box by replacing m and b with the appropriate values.
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327 PM
7/3/2001

Answers

Answer:

[tex]y=\frac{1}{2}x+5[/tex]

Step-by-step explanation:

Hi there!

Slope intercept form: [tex]y=mx+b[/tex] where m is the slope and b is the y-intercept (the value of y when x is 0)

1) Determine the slope (m)

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex] where two points that lie on the line are [tex](x_1,y_1)[/tex] and [tex](x_2,y_2)[/tex]

Plug the given points (-4,3) and (6,8) into the equation

[tex]m=\frac{8-3}{6-(-4)}\\m=\frac{8-3}{6+4}\\m=\frac{5}{10}\\m=\frac{1}{2}[/tex]

Therefore, the slope of the line is [tex]\frac{1}{2}[/tex]. Plug this into [tex]y=mx+b[/tex] :

[tex]y=\frac{1}{2}x+b[/tex]

2) Determine the y-intercept (b)

[tex]y=\frac{1}{2}x+b[/tex]

Plug in one of the given points and solve for b

[tex]8=\frac{1}{2}(6)+b\\8=3+b[/tex]

Subtract 3 from both sides to isolate b

[tex]8-3=3+b-3\\5=b[/tex]

Therefore, the y-intercept is 5. Plug this back into [tex]y=\frac{1}{2}x+b[/tex]:

[tex]y=\frac{1}{2}x+5[/tex]

I hope this helps!

A family has 5 children. Compute the probabilities of the following events:
All five are born on Friday.
Each one is born on a different day of the week.

Answers

I think the answer is 10% and 90%

Answer:

1/16,807 chance that they all will be born on Friday

Probably 5/7, but don't take my word for it.

Step-by-step explanation:

There are 7 days of the week.

There is a 1/7 chance for one kid to be born on a certain day of the week.

We can attach an exponent of 5 since the 1/7 is a constant, and I'm not going to bother typing the same thing over and over again.

(1/7)^5 = 1/16,807.

The probability of all of them being born on Friday or anyday is 1/16,807.

The probability of each person being born on a different day of the week is  probabily going to be 5/7, but it could be different, because you need to factor in the requirement that they are not born on the same day.

I can guarantee that the first question is probably correct, but not the second.

Linda found that the cost to get a swimming pool installed in her backyard is a linear function of the pool's area. A swimming pool with an area of 1,000 square feet can be installed for $50,000, whereas the installation of an 800 square foot swimming pool costs $35,000. Select the correct graph that models the given relationship.

Answers

Answer:

$35,000

Step-by-step explanation:

if $50,000 is to install an area of 1,000 square feet swimming pool and $35,000 can be used to install an 800 square foot swimming pool I think the best graph model is 800 square feet for $35,000 for a cost cut of $15,000 is a good bargain

The total sound power, in decibels, from x objects each producing 50 decibels of sound power is given by the function f(x) = 50 + 10 log x. Suppose each of the x objects increases its sound power by 10 decibels, so that the new total sound power, in decibels, is given by the function g(x) = f(x) + 10. Which shows the graphs of f(x) and g(x)? On a coordinate plane y = g (x) starts at (0, 60) and curves up through (10, 70). Y = f (x) starts at (0, 50) and curves up through (10, 60). On a coordinate plane y = f (x) starts at (0, 50) and curves up through (10, 60). y = g (x) starts at (0, 40) and curves up through (10, 50). On a coordinate plane, y = f (x) starts at (0, 50) and curves up through (10, 60). Y = g (x) starts at (10, 50) and curves up through (20, 60). On a coordinate plane, y = g (x) starts at (negative 10, 50) and curves up through (0, 60). Y = f (x) starts at (0, 50) and curves up through (10, 60). Mark this and return

Answers

Answer:

Graph A

Step-by-step explanation:

correct answer on edge :)

The statement that represents the graphs of the functions f(x) and g(x) : On a coordinate plane y = g (x) starts at (0, 60) and curves up through (10, 70). Y = f (x) starts at (0, 50) and curves up through (10, 60).

What is a function?"It defines a relation between input and output values.""In function, for each input there is exactly one output."

For given question,

The total sound power, in decibels, from x objects each producing 50 decibels of sound power is given by the function f(x) = 50 + 10 log x.

If each of the x objects increases its sound power by 10 decibels, then the new total sound power, in decibels, is given by the function

g(x) = f(x) + 10.

The graph of the function f(x) would starts at (0, 50)

For x = 10 the value of the function f(x) would be,

f(10) = 50 + 10 log (10)

f(10) = 50 + 10 (1)

f(10) = 60

This means, the graph of the function f(x) passes though point (10, 60)

Also, the graph of the function g(x) would starts at (0, 60)

For x = 10 the value of the function g(x) would be,

g(10) = f(10) + 10

g(10) = 60 + 10

g(10) = 70

This means, the graph of the function g(x) passes though point (10, 70)

Therefore, on a coordinate plane y = g (x) starts at (0, 60) and curves up through (10, 70). Y = f (x) starts at (0, 50) and curves up through (10, 60).

Learn more about the graph of a function here:

https://brainly.com/question/27757761

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The principle of redundancy is used when system reliability is improved through redundant or backup components. Assume that a​ student's alarm clock has a 15.3​% daily failure rate. Complete parts​ (a) through​ (d) below. a. What is the probability that the​ student's alarm clock will not work on the morning of an important final​ exam?

Answers

Answer:

[tex]Pr = 0.153[/tex]

Step-by-step explanation:

Given

[tex]p = 15.3\%[/tex]

Required

Probability of alarm not working

[tex]p = 15.3\%[/tex] implies that the alarm has a probability of not working on a given day.

So, the probability that the alarm will not work on an exam date is:

[tex]Pr = 15.3\%[/tex]

Express as decimal

[tex]Pr = 0.153[/tex]

Quadrilateral A'B'C'D'A

B

C

D

A, prime, B, prime, C, prime, D, prime is the result of dilating quadrilateral ABCDABCDA, B, C, D about point AAA by a scale factor of \dfrac{1}{2}
2
1

start fraction, 1, divided by, 2, end fraction.

Answers

Answer:

[tex]A' = (2,0)[/tex]

Step-by-step explanation:

Given

See attachment for ABCD

[tex]k = \frac{1}{2}[/tex] --- the scale factor

Required

The coordinates of A'

From the attachment, we have:

[tex]A = (4,0)[/tex]

So:

[tex]A' = k * A[/tex]

[tex]A' = \frac{1}{2} * (4,0)[/tex]

[tex]A' = (2,0)[/tex]

Answer:

on khan, both are false

Step-by-step explanation:

What transformation to the linear parent function, f(x) = x, gives the function
g(x) = x + 7?
A. Shift 7 units left.
B. Shift 7 units right.
C. Vertically stretch by a factor of 7
D. Shift 7 units down

Answers

Answer:

I think A

Step-by-step explanation:

Find the volume of the cement block in the figure shown.


Please help :)

Answers

9514 1404 393

Answer:

  1240 in³

Step-by-step explanation:

The overall dimensions of the block are ...

  10 in by 11 in by 17 in

The volume of that space is ...

  V = LWH = (10 in)(11 in)(17 in) = 1870 in³

The volume of each of the three identical holes is similarly found:

  V = (10 in)(3 in)(7 in) = 210 in³

Then the volume of the block is the overall volume less the volume of the three holes:

  = 1870 in³ - 3(210 in³) = 1240 in³

Assuming the probability of a single sample testing positive is 0.15​, find the probability of a positive result for two samples combined into one mixture. Is the probability low enough so that further testing of the individual samples is rarely​ necessary?

Answers

Answer:

[tex]P(Positive\ Mixture) = 0.2775[/tex]

The probability is not low

Step-by-step explanation:

Given

[tex]P(Single\ Positive) = 0.15[/tex]

[tex]n = 2[/tex]

Required

[tex]P(Positive\ Mixture)[/tex]

First, we calculate the probability of single negative using the complement rule

[tex]P(Single\ Negative) = 1 - P(Single\ Positive)[/tex]

[tex]P(Single\ Negative) = 1 - 0.15[/tex]

[tex]P(Single\ Negative) = 0.85[/tex]

[tex]P(Positive\ Mixture)[/tex] is calculated using:

[tex]P(Positive\ Mixture) = 1 - P(All\ Negative)[/tex] ---- i.e. complement rule

So, we have:

[tex]P(Positive\ Mixture) = 1 - 0.85^2[/tex]

[tex]P(Positive\ Mixture) = 1 - 0.7225[/tex]

[tex]P(Positive\ Mixture) = 0.2775[/tex]

Probabilities less than 0.05 are considered low.

So, we can consider that the probability is not low because 0.2775 > 0.05

Today, 11:50
Sawing and cutting. Level
Arjun cut a loaf of bread and made
sandwiches. How many sandwiches did he
make if he made 10 cuts?

Answers

Answer:

5 sandwiches he made in bread

the answer is 5 sandwiches

NFL Pre-Season Teams in the National Football League (NFL) in the US play four pre-season games each year before the regular season starts. Do teams that do well in the pre-season tend to also do well in the regular season? We are interested in whether there is a positive linear association between the number of wins in the pre-season and the number of wins in the regular season for teams in the NFL.

Required:
a. What are the null and alternative hypotheses for this test?
b. The correlation between these two variables for the 32 NFL teams over the 10 year period from 2005 to 2014 was 0.067. Use this sample (with n=320) to calculate the appropriate test statistic and determine the p-value for the test.
c. State the conclusion in context, using a 5% significance level.

Answers

Answer:

H0 : ρ = 0

H1 : ρ ≠ 0

Test statistic = 1.197

Pvalue = 0.2335

There is no correlation between the two variables

Step-by-step explanation:

The null and alternative hypothesis :

H0 : No correlation exist,

H1 : Correlation exist

H0 : ρ = 0

H1 : ρ ≠ 0

Test statistic, T = r / √(1 - r²) / (n - 2)

T = 0.067 / √(1 - 0.067²) / (320 - 2)

T = 0.067 / √(0.995511 / 318)

T = 0.067 / 0.0559512

T = 1.197

The Pvalue obtained from the Rscore, at df = 320 - 2 = 318 is 0.2335

α = 5% = 0.05

The Pvalue > α ; we fail to reject the null and conclude that, there is no correlation between the two variables.

Find the circumference of a circle in terms of u with a radius of 10 ft.
100n ft
10 ft
5 ft
62.87 ft
20 ft

Answers

Answer:

[tex]2 \times \frac{22}{7} \times 10 = 62.87 [/tex]

At a local university the students have been overdosing on caffeine to help them study for exams. However, many students have been getting quite sick from taking too much coffee and cola.
A. How many cups of coffee would be too much and at the dangerous level (3.00 g)? You know that coffee contains 21.5 mg caffeince per ounce and a cup is 8 oz.
B. How many cans of cola would be too much and at the dangerous level? You know that cola contains 4.20 mg per ounce and a soft drink can contain 12.0 oz.

Answers

Answer:

A) Hence, the number of coffee cups that are risky = 17.4 Cups.

B) Here, the number of coffee cups that are risky = 59.5 Colas.

Step-by-step explanation:

A)

In 1 cup coffee  =[tex]8\times21.5mg= 172.0 mg[/tex]

Hence one cup of coffee contains 172 mg of caffeine. The risky level is 3000mg.

Therefore, the number of coffee cups that are risky

                                                         [tex]= 3000/172\\ \\=17.4 cups[/tex]

Here, the number of coffee cups that are risky = 17.4 cups.

B)

[tex]1 cola=12\times4.2mg\\\\ = 50.4mg / day[/tex]

Hence, one can cola contains 50.4 mg of caffeine.

The dangerous level is 3000 mg.

Therefore, the number of cola cans that are risky [tex]=3000/50.4= 59.5[/tex] cola is risky.

Acellus
First, find the surface area of the yellow prism.
3 cm 3 cm
: ?
4 cm
3 cm
front: [?]
back: [ ]
right: [ ]
left: [ ]
3cm
3cm
4cm
top:[]
5 cm
TOTAL: [ ]
Note: The bottom will not be
included because this is whern
5 cm

Answers

Answer:

57 cm²

Step-by-step explanation:

Surface area of the yellow prism = front + back + right + left + top

✔️Area of the front = L * W

L = 4 cm

W = 3 cm

Area of the front = 4*3 = 12 cm²

✔️Area of the back = L * W

L = 4 cm

W = 3 cm

Area of the back = 4*3 = 12 cm²

✔️Area of the right face = L * W

L = 4 cm

W = 3 cm

Area of the right face = 4*3 = 12 cm²

✔️Area of the left face = L * W

L = 4 cm

W = 3 cm

Area of the left face = 4*3 = 12 cm²

✔️Area of the top = L * W

L = 3 cm

W = 3 cm

Area of the top = 3*3 = 9 cm²

✅Total = 12 + 12 + 12 + 12 + 9 = 57 cm²

A coin is tossed times and comes up heads times. Use the Empirical Method to approximate the probability that the coin comes up heads. Round your answer to four decimal places as necessary.

Answers

Answer:

[tex]P(head) = 0.5600[/tex]

Step-by-step explanation:

Given

[tex]n = 500[/tex] -- number of toss

[tex]head = 280[/tex] --- outcomes of head

See comment

Required

Empirical probability of head

This is calculated as:

[tex]P(head) = \frac{n(head)}{n}[/tex]

[tex]P(head) = \frac{280}{500}[/tex]

[tex]P(head) = 0.5600[/tex]

Samantha acored 15 points in her laat
basketball game. She made 3 free throwa
that are worth 1 point each. The rest of
her pointa came on 2 point field goala,
Write an equation that can be used to find
the number of 2 point field goals that
Samantha made
(uae p as your variable)



Help fasttt

Answers

Answer:

15=2p+3

Step-by-step explanation:

Ben starts walking along a path at 3 mi/h. One and a half hours after Ben leaves, his sister Amanda begins jogging along the same path at 7 mi/h. How long (in hours) will it be before Amanda catches up to Ben?



Enter the exact answer.
Hint: The distance formula is that distance = rate * time, so for example in one and a half hours, Ben has walked 3 * 1.5 miles.

Amanda catches up to Ben in ____________ hours.

Answers

Answer:

1.125 hours

Step-by-step explanation:

Given :

Ben's speed = 3 mi/hr

Time before Amanda starts = 1.5 hours

Amanda's speed = 7 mi/hr

Time before Amanda catches up with Ben

Recall :

Distance = speed * time

Distance already covered by Ben before Amanda starts :

(3 * 1.5) = 4.5

Hence, we can setup the equation :

Ben's distance = Amanda's distance

Let time taken = x

4.5 + 3x = 7x

4.5 = 7x - 3x

4.5 = 4x

x = 4.5 / 4

x = 1.125 hours

1.125 * 60 = 67. 5 minutes

Given the functions below, find f(x)+g(x)

CHECK MY ANSWERS PLEASE

Answers

The answer is (a)..........

(7+3i)-(3-9i)complex numbers

Answers

Answer:

C

Step-by-step explanation:

For this, you want to treat i like any other variable, and combine like terms. However you need to keep in mind that there is a negative sign before the second set of parentheses. This means everything inside it should have a negative before it. So we can write it like this:

(7 + 3i) - (3 - 9i)

7 + 3i -3 +9i

4 + 12i

Hope that helps!

The sum of four consecutive odd integers is –72. Write an equation to model this situation, and find the values of the four integers.

Answers

9514 1404 393

Answer:

(x -3) +(x -1) +(x +1) +(x +3) = -72-21, -19, -17, -15

Step-by-step explanation:

Let x represent the even integer between the middle two odd integers. Then the sum of the four odd integers is ...

  (x -3) +(x -1) +(x +1) +(x +3) = -72

  4x = -72

  x = -18

The four integers are -21, -19, -17, -15.

_____

Additional comment

You could let x represent one of the integers. Often, people choose to let it represent the least of them. Then the equation becomes x +(x+2) +(x+4) +(x+6) = -72, so 4x = -84 and x = -21. This introduces a "subtract 12" step in the solution process that is unnecessary if x is chosen to be the average of the integers.

As the average, x is the sum divided by the number of them, so you know x=-72/4 = -18 immediately. Then you just have to find the nearest two odd integers below and above -18. You can do the whole problem mentally.

Anyone know this question?

Answers

Answer:

All of these

Step-by-step explanation:

Given

[tex]f(5) = 11[/tex]

[tex]f(x)[/tex] at [tex](5,11)[/tex]

Required

Interpret

[tex]f(5) = 11[/tex] mean that: the function is at [tex](5,11)[/tex]

In other words:

[tex]x = 5; y = 11[/tex]

It also means:

Substitute 5 for x and the result will be 11

Hence, all options are true

I need help solving this problem. Thanks

Answers

Answer:

Step-by-step explanation:

they say by noon 4 inches of rain has fallen,    then the say that it's falling at  1/4 inch per hour

f(x) = 1/4x +4

where x is in hours, and  f(x)  represents the linear graph of the amount of rain that has fallen after noon   :)

so by 2:30   or  2.5 hours....  then

f(2.5) = 1/4x +4

y = 1/4 (2.5) +4  ( i moved to the y  b/c now there is an answer)

y =[tex]\frac{5}{8}[/tex] + 4

y =4[tex]\frac{5}{8}[/tex]   inches of rain

Answer:

a) y = 1/4x + 4

b) 4.625 inches

Step-by-step explanation:

a) y(0) = 4 inches

slope = 1/4 rate

y = 1/4x + 4

b) 12:00pm (noon) to 2:30pm = 2 hours 30 mins = 2.5 hours

y = 1/4x + 4

y = (1/4)(2.5) + 4

y = 0.625 + 4

y = 4.625 inches

You have been doing research for your statistics class on the prevalence of severe binge drinking among teens. You have decided to use 2011 Monitoring the Future (MTF) data that have a scale (from 0 to 14) measuring the number of times teens drank 10 or more alcoholic beverages in a single sitting in the past 2 weeks.
a. According to 2011 MTF data, the average severe binge drinking score, for this sample of 914 teens, is 1.27, with a standard deviation of 0.80. Construct the 95% confidence interval for the true averse severe binge drinking score.
b. On of your classmates, who claims to be good at statistics, complains about your confidence interval calculation. She or he asserts that the severe binge drinking scores are not normally distributed, which in turn makes the confidence interval calculation meaningless. Assume that she or he is correct about the distribution of severe binge drinking scores. Does that imply that the calculation of a confidence interval is not appropriate? Why or why not?

Answers

Answer:

(1.218 ; 1.322)

the confidence interval is appropriate

Step-by-step explanation:

The confidence interval :

Mean ± margin of error

Sample mean = 1.27

Sample standard deviation, s = 0.80

Sample size, n = 914

Since we are using tbe sample standard deviation, we use the T table ;

Margin of Error = Tcritical * s/√n

Tcritical at 95% ; df = 914 - 1 = 913

Tcritical(0.05, 913) = 1.96

Margin of Error = 1.96 * 0.80/√914 = 0.05186

Mean ± margin of error

1.27 ± 0.05186

Lower boundary = 1.27 - 0.05186 = 1.218

Upper boundary = 1.27 + 0.05186 = 1.322

(1.218 ; 1.322)

According to the central limit theorem, sample means will approach a normal distribution as the sample size increases. Hence, the confidence interval is valid, the sample size of 914 gave a critical value at 0.05 which is only marginally different from that will obtained using a normal distribution table. Hence, the confidence interval is appropriate

Which of the following is a like radical to cube rt of 7x

Answers

Answer:

[tex]\sqrt[3]{7x}[/tex]

Step-by-step explanation:

Given

[tex]7x[/tex]

Required

The radical statement

Cube root is represented as:

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

Considering [tex]7x[/tex], the expression is:

[tex]\sqrt[3]{7x}[/tex]

A 19 in. monitor has a length of 16 in. What is its width?

10.25 in.
14.64 in.
16.51 in.
18.91 in.

Answers

This makes no sense but probably 14.64

SOMEONE HELP PLEASE! I don’t know how to solve this problem nor where to start? Can some please help me out and explain how you got the answer please. Thank you for your time.

Answers

That is the answer to your question

What iis 155 plus 33 minus 4 divided by 2

Answers

Answer:

155+33-4÷2155+33-2188-2186

hope it is helpful to you

The simplified form of statement 155 plus 33 minus 4 divided by 2 is

186.

What is a numerical expression?

A numerical expression is a mathematical statement written in the form of numbers and unknown variables. We can form numerical expressions from statements.

Addition is also known as the sum, subtraction is also known as the difference, multiplication is also known as the product, and division is also known as the factor.

The given statement is 155 plus 33 minus 4 divided by 2 which can be numerically expressed as,

155 + 33 - 4 ÷ 2.

PEMDAS rule states the correct order of simplifying an expression is as follows, Parenthesis, exponents, multiplications, divisions, additions, and, subtractions.

155 + 33 - 2.

= 188 - 2.

= 186.

learn more about numerical expressions here :

https://brainly.com/question/29199574

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4) Write the equation of the line passing
through (-5, 6 ) and has slope equal to 4.

Answers

Answer:

y = 4x + 26

Step-by-step explanation:

y = mx + b

The slope (m) is equal to 4.

y = 4x + b

To find the y-intercept (b), plug in the point given.

6 = 4(-5) + b

6 = -20 + b

26 = b

The answer is y = 4x + 26.

Answer:

The equation of the line passing through (-5, 6) with a slope of 4 is

y = 4x + 26

Step-by-step explanation:

An equation of a line would always have the following structure...

y = mx + b

In this equation, "y" is the y coordinate of the point, "x" is the x coordinate of the point, "m" is the slope, and "b" is the y coordinate of the y-intercept. We know all the values except "b", but we can find the value of "b" by substituting all the other values into the equation...

y = mx + b

6 = 4(-5) + b

6 = b - 20

b = 6 + 20

b = 26

Therefore, the equation of the line passing through (-5, 6) with a slope of 4 is y = 4x + 26

Find the domain and range of the relation

Answers

Answer:

The domain is "all real numbers" and the range is x more than -3

Sebastian is going to choose the color pattern

Answers

Answer:

use blue red blue red

Step-by-step explanation:

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