Suppose that an examination consists of 10 questions with the choice A, B, C, and D. Assume that a student has no knowledge of the subject matter. Then what is the probability that: Guessing at most two correct answers? Guessing at least seven correct answers? Which type of probability distribution it has? Why? average five smokers pass a crain traat B. C. Suppose that an examination consists of 10 questions with the choice A , B , C , and D. Assume that a student has no knowledge of the subject matter . Then what is the probability that : Guessing at most two correct answers ? Guessing at least seven correct answers ? Which type of probability distribution it has ? Why ? ​

Answers

Answer 1

The probability of getting two correct answers will be 0.0625.

How to calculate the probability?

The probability of getting two correct answers will be:

Probability of getting the correct answer will be:

= 1/4 = 0.25

The probability of getting two correct answers will be:

= 0.25 × 0.25

= 0.0625

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Related Questions

Consider the table that includes the input and output values of a function.



Which best describes the constant difference for the function?

a constant second difference of –6
a constant second difference of 8
a constant third difference of –6
a constant third difference of 8

Answers

The first option is correct and it best describes the constant difference for the function as a constant second difference of –6.

What is a function?

A function f(x) is the relation between a set of inputs resulting and producing the desired output value of y for each input.

From the given information:

x          f(x)           first difference        second difference   third difference

-2         0                    -                              -                              -

-1         -10            (-10-0)/-1--2 = -10           -                             -

0         -12            (-12 - 10)/0 -- 1= -2     (-2-10)/2 = -6              -

1          -12            (-12--12)/1-0 = 0         (0-2)/2 =  -1              (-1+6)/2 = 5/2

2         -16             (-16--12)/2-1 = -2       (-2-0)/2 = -1              (-1+1)/2 = 0

Therefore, we can conclude that the constant difference for the function is a constant second difference of –6.  

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Answer:

A

Step-by-step explanation:

The number of wrecks at a certain intersection varies directly as the number of cars that travel through the intersection. If there are 31 wrecks when 1,085 cars have traveled through the intersection, how many cars have passed through the intersection after 7 wrecks?

Answers

Answer:

Step-by-step explanation:

Comment

This can be done as a proportion. A proportion is 2 equal ratios. If you know three parts of the proportion then you can solve for the 4th.

Proportion

31 wrecks/1085 cars = 7 wrecks / x cars

Solution

31 wrecks/1085 cars = 7 wrecks / x cars        Cross Multiply

31 * x = 1085 * 7                                                Simplify the right

31 * x = 7595                                                     Divide both sides by 31

31 * x/31 = 7595/31

x = 245

Answer 7 wrecks means 245 cars have passed the intersection

supposed an individual has a body fat percentage of 17.5% and weighs 164 lbs. how many pounds of his weight is made up of fat? round your answer to the nearest tenth.

Answers

The amount of pounds of his weight is made up of fat is 28.7lbs

Percentages and values

Given the following parameters

Total weight of body = 164lbs

Percentage fat = 17.5%

Determine the amount made up of fat

Fat amount = 17.5% of 164

Fat amount = 0.175 * 164

Fat amount = 28.7lbs

Hence the amount of pounds of his weight is made up of fat is 28.7lbs

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Please help! Will give the brainliest :)

Answers

Answer: J. A translation of △XYZ to the right.

Step-by-step explanation:

I'll explain each bullet point one by one. A good hint is to pay attention to where the letters are.

-J is correct because the figure was shifted to the right.

-K is incorrect because if it was a reflection across the x-axis, the figure would be in Quadrant 3, or the bottom left.

-L is incorrect because if you pay attention to the letters, they are in the exact same place. If it was a reflection across the y-axis, the X' and Y' would switch places if you know what I mean.

-M is incorrect because if the figure was rotated 90°, point Z' would be furthest from the x-axis. In other words, the triangle would have been pointing up and not down.

-N is incorrect because if the figure was rotated 180° clockwise, the figure would have been in Quadrant 4, or the bottom right.

Given this information, the most appropriate answer is J.

I hope this helps! Pls give brainliest!! :)

Complete this shape so that it is symmetrical about the reflection line

Answers

A balanced and proportionate likeness observed in two sides of an item is characterized as symmetry. The shape can be completed as shown below.

What is symmetry?

A balanced and proportionate likeness observed in two sides of an item is characterized as symmetry. It signifies that one side is a mirror image of the other. The line of symmetry is the imaginary line or axis along which you can fold a figure to produce the symmetrical halves.

The shape can be completed as shown below, so that the complete shape is symmetrical about the given axis.

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There are 10 USB drives in a box and 3 are defective. Two drives are to be selected, one after the other. What is the probability of selecting a defective USB followed by another defective USB?

Answers

[tex]|\Omega|=10\cdot9=90\\|A|=3\cdot2=6\\\\P(A)=\dfrac{6}{90}=\dfrac{1}{15}\approx6.7\%[/tex]

If BC is 1

CD is 2

DA is 3

AB is 4,

what is EF?

Answers

The length of the side EF will be 1 unit, approximately.

The complete figure is attached below.

What is Geometry?

It deals with the size of geometry, region, and density of the different forms both 2D and 3D.

The figure is given below.

The length of EF will be

EF = CF – CE

Then the value of CF will be

CF = BC × cos 30

CF = 2 × 0.866

CF = 1.732

Then the value of CE will be

CE = BC × cos 42

CE = 1 × 0.743

CE = 0.743

Then we have

EF = 1.732 – 0.743

EF = 0.989 ≈ 1

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Quadrilateral ABCD is inscribed in this circle. What is the measure of angle C?

Answers

Answer:

[tex]\boxed{\bf \angle \: C = 62^{o} }[/tex]

Step-by-step explanation:

The sum of the opposite angle of cyclic quadrilateral is 180°.

First, lets find x...

[tex]\bf \angle \: B + \angle \: D = {180}^{o} [/tex][tex]\bf (x + 20) + 3x = {180}^{o} [/tex][tex]\bf 4x + 20 = 180[/tex][tex]\bf 4x = 180 - 20[/tex][tex]\boxed{\bf x = {40}^{o}} [/tex]

Now, let's find the measure of angle C....

[tex]\bf \angle \: a + \angle \: C = {180}^{o} [/tex][tex]\bf 2x + 38 + \angle \: C = {180}^{o} [/tex][tex]\bf 2(40) + 38 + \angle \: C = {180}^{o} [/tex][tex]\bf \angle \: C = 180 - 80 - 38[/tex][tex]\boxed{\bf \angle \: C = {62}^{o}}[/tex]

________________________

Each point has been reflected over the x-axis or y-axis.


Select the axis over which each point has been reflected.

Answers

The reflection is

x-axisx-axisy-axis

What is reflection over axis?

A reflection of a point, a line, or a figure in the X axis involved reflecting the image over the x axis to create a mirror image. In this case, the x axis would be called the axis of reflection.

For reflecting over the X axis is to negate the value of the y-coordinate of each point, but leave the x-value the same.

and, for reflecting over the Y axis is to negate the value of the x-coordinate of each point, but leave the y value the same.

So, by considering the above value rules the reflection of the given points as follows over respective axis.

E(7, 1) ⇒ (7, -1)

Here, the reflection is over x-axis because the y value is changing

F(-3, 5) ⇒ (-3, -5)

Here, the reflection is over x-axis because the y value is changing

G(6, -2) ⇒ (-6, -2)

Here, the reflection is over y-axis because the x value is changing.

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Which of the following are characteristics of the graph of the square root
parent function? Check all that apply.

Answers

Answer:

C.  It is in Quadrant I

D.  It starts at the origin

Step-by-step explanation:

Parent function:  [tex]f(x)=\sqrt{x}[/tex]

Domain: set of all possible input values (x-values)

As the square root of a negative number does not exist in the set of Real Numbers, the domain for the parent function is:

Solution:  x ≥ 0Interval notation:  [0, ∞)

Range: set of all possible output values (y-values)

As the domain of the parent function is x ≥ 0, the range will be:

Solution:  f(x) ≥ 0Interval notation:  [0, ∞)

As the range and domain both begin at zero, the graph of the parent function starts at the origin (0, 0).

Quadrant: a region of the Cartesian plane formed when the x-axis and y-axis intersect each other.

Quadrant I:  (x, y)

Quadrant II:  (-x, y)

Quadrant III: (-x, -y)

Quadrant IV:  (x, -y)

Therefore, as the range and domain of the parent function are positive, the graph is in Quadrant I.


If f(x) = 3x-2 and g(x) = x+²,
find f(g(x)).
f(g(x)) = [?]
Simplify your answer as much as possible.

Answers

Answer:

x

Step-by-step explanation:

[tex]f(g(x)) = 3(\frac{x+2}{3} )-2\\= x + 2 - 2\\= x[/tex]

What is the range of the function y=3√x+8?
O-∞ O-8 O 0≤y<∞
O 2≤y<∞

Answers

Answer: 0 ≤ y < ∞

Step-by-step explanation:

   First, let us graph the function. See attached.

-> If I graphed the formatting of the square root sign incorrectly, please let me know so I can fix the answer.

  The range of the function is all of the function's output values. In this case, all of the y values.

        0 ≤ y < ∞


Jessie bought a vacuum cleaner priced at $79 with a 6% sales tax rate. What is the total cost of the vacuum cleaner after-
tax?

Answers

Answer:

83.74

Step-by-step explanation:

First find the amount of the tax

79 * .06

4.74

Add this to the original price

79+4.74

83.74

a straight line passes through points A(-2,6) and B(4,2). M is the midpoint of line AB.Find the coordinates of M​

Answers

Answer:

(1,4)

Step-by-step explanation:

What are m and b in the linear equation y=2x+8

Answers

Answer:

m=2 and b=8

Step-by-step explanation:

this is a linear equation, which takes on the formula of y=mx+b
therefore in the equation y=2x+8, 2 is the m, and 8 is the b

Find the area (in square units) of the region under the graph of the function f on the interval [-1,5].

F(X) = 2x+8

Square units: ?

Answers

Answer:

So generally, when you're trying to find the area under the curve, you want to integrate the function within the bounds in question, which in this case is 3 and 5. As a result, you get 4e^x - x^2/2. Then you want to subtract this when you put 3 in for x from when you put 5 in for x, such as the following:

(4e^5-25/2) - (4e^3 - 9/2)

When you combine like terms, you end up with the following answer:

4e^5 - 4e^3 - 8 square units

However, you can approximate the answer to 505.31 square units

Simplify: √64(6z-7)² (square root over entire equation)

Answers

[tex]\sqrt{64(6z-7)^2}=\sqrt{64}\cdot\sqrt{(6z-7)^2}=8\cdot |6z-7|=8|6z-7|[/tex]

What is the equation of the line perpendicular to 2x - 3y = 13 that passes through the point (-6, 5)?
y=x+9
y=-3x-4
y=-x-13
y-x-1

Answers

Rewriting the equation of the given line in slope-intercept form,

[tex]2x-3y=13\\\\2x-13=3y\\\\y=\frac{2}{3}x-\frac{13}{3}[/tex]

Thus, the slope of the given line is 2/3. Since perpendicular lines have slopes that are negative reciprocals of each other, we want to find the line with a slope of -3/2.

Substituting into point-slope form,

[tex]y-5=-\frac{3}{2}(x+6)\\\\y-5=-\frac{3}{2}x-9\\\\\boxed{y=-\frac{3}{2}x-4}[/tex]

he table shows the height of water in a pool as it is being filled. A table showing Height of Water in a Pool with two columns and six rows. The first column, Time in minutes, has the entries, 2, 4, 6, 8, 10. The second column, Height in inches, has the entries, 8, 12, 16, 20, 24. The slope of the line through the points is 2. Which statement describes how the slope relates to the height of the water in the pool? The height of the water increases 2 inches per minute. The height of the water decreases 2 inches per minute. The height of the water was 2 inches before any water was added. The height of the water will be 2 inches when the pool is filled.

Answers

The height of water increases by 2 inches per minute option first "The height of the water increases 2 inches per minute" is correct.

What is the slope?

The ratio that y increase as x increases is the slope of a line. The slope of a line reflects how steep it is, but how much y increases as x increases. Anywhere on the line, the slope stays unchanged (the same).

[tex]\rm m =\dfrac{y_2-y_1}{x_2-x_1}[/tex]

We have given a table:

Time     height

2                8

4               12

6                16

8               20

10              24

The slope of the line = (12-8)/(4-2) = 4/2 = 2

The value of the slope is positive we can say,  the height of water increases as time passes.

Thus, the height of water increases by 2 inches per minute option first "The height of the water increases 2 inches per minute" is correct.

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the answer is A: The height of the water increases 2 inches per minute.

hope this helped :)

The graph below shows the solution to which system of inequalities?

Answers

Inequalities help us to compare two unequal expressions. The inequalities that represent this graph are y<8/10x and y>-x. The correct option is C.

What are inequalities?

Inequalities help us to compare two unequal expressions. Also, it helps us to compare the non-equal expressions so that an equation can be formed.

It is mostly denoted by the symbol <, >, ≤, and ≥.

To find the inequality, we need to find the equation of the dashed line and then substitute the inequality as per the requirement. The dashed line is used instead of a solid line to show greater than or less than.

The inequality for the first graph can be written as,

[tex]y < \dfrac{8}{10}x[/tex]

The inequality for the second graph will be,

y>-x

Hence, the inequalities that represent this graph are y<8/10x and y>-x. Thus, the correct option is C.

The complete question is:

The graph below shows the solution to which system of inequalities?

A.) y>x , y ≥ (8/10)x

B.) y>-x, y ≤ (8/10)x

C.) y>-x, y < (8/10)x

D.) y>x, y > (8/10)x

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Help me PLEASEEE!!! ASAP

Answers

V=14.4 is the answer to ur question my friend

There are two colored marbles and one white marble in a box. Julie mixes the marbles and then Sam draws two marbles at random without replacement. If the two marbles match, Sam wins; otherwise, Julie wins. Does each player have an equal chance of winning? Will adding another white marble give each player an equal chance of winning? What if a game with the same rules was played using three colored marbles and one white marble?

Answers

at first there are three marbles for Sam to pick from. the possibility of drawing a colored marble is 2/3. if Sam picks one of the colored marbles, the possibility of therefore (if he'd drawn the colored marble) drawing the second colored marble is 1/2. for the possibility of those happening consequently, we have to multiply the possibilities. 2/3 * 1/2 is 2/6 is 1/3. which means Sam wins in 33.333...% cases. Julie has a better chance of winning.

adding a white marble would change the possibilities to 1/2 and 1/3 consequently, meaning Sam wins in 1/2 * 1/3 = 1/6 = 16.7% cases, which is even less fair.

adding a colored marble would change the possibilities to 3/4 and 2/3 consequently, meaning Sam wins in 3/4 * 2/3 = 6/12 = 50% cases, which finally makes the game fair.

In 2009, there were 12,078 Burger King restaurants; in 2017, there were 16,717 Burger King restaurants. Calculate the average rate of change (slope) for the number of Burger King restaurants over this time period.

Answers

The average rate of change (slope) is 579.875 if, in 2009, there were 12,078 Burger King restaurants; in 2017, there were 16,717 Burger King restaurants.

What is the slope?

The ratio that y increase as x increases is the slope of a line. The slope of a line reflects how steep it is, but how much y increases as x increases. Anywhere on the line, the slope stays unchanged (the same).

[tex]\rm m =\dfrac{y_2-y_1}{x_2-x_1}[/tex]

We have:

In 2009, there were 12,078 Burger King restaurants; in 2017, there were 16,717 Burger King restaurants.

The slope:

[tex]\rm m =\dfrac{16717-12078}{2017-2009}[/tex]

m = 4639/8

m = 579.875

Thus, the average rate of change (slope) is 579.875 if, in 2009, there were 12,078 Burger King restaurants; in 2017, there were 16,717 Burger King restaurants.

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Max is going to order a breakfast platter at The Breakfast Club. He can choose one style of eggs, one type of meat, and one kind of toast. The following table shows the options available to him.
Breakfast platter
Egg options Fried, Scrambled, Poached, Hard boiled
Meat options Bacon, Sausage, Ham, Steak
Toast options White, Wheat, Rye
How many different breakfast platters could Max create?

Answers

the answer is 48

Step-by-step explanation:

since there are 4 egg options 4 meat options and 3 bread options. so u multiply this.

4×3×4=48

A soccer league has 160 players. Of those players 50% are boys. How many boys are in the soccer league?

Answers

Answer:

80 boys

Step-by-step explanation:

160 total players

50% are boys

50% of 160 is 80

Giraffe Jack is 19 feet tall, and Ostrich Jim is 9 feet tall. A) What percent of Jack's height is Jim's height? B)What percent of Jim's height is Jack's height?

Answers

A percentage is a way to describe a part of a whole. Jim's Height is 47.37% of Jack's height.

What are Percentages?

A percentage is a way to describe a part of a whole. such as the fraction ¼ can be described as 0.25 which is equal to 25%.

To convert a fraction to a percentage, convert the fraction to decimal form and then multiply by 100 with the '%' symbol.

Giraffe Jack is 19 feet tall, and Ostrich Jim is 9 feet tall.

A.) The percent of Jack's height is Jim's height,

Percentage = (Height of Jack/Height of Jim) × 100%

                   = 19/9 × 100%

                   = 211.11%

Hence, Jack's Height is 211.11% of Jim's height.

B.) The percent of Jim's height is Jack's height,

Percentage = (Height of Jim/Height of Jack) × 100%

                   = 9/19 × 100%

                   = 47.37%

Hence, Jim's Height is 47.37% of Jack's height.

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Answer:

211.11%

Step-by-step explanation:

The area of a rectangle is 44m2 , and the length of the rectangle is 3m
less than double the width. Find the dimensions of the rectangle.

Answers

Answer:

width=11/2

length=8

Step-by-step explanation:

44=(2w-3) x w area for a rectangle (44) = the length (2w-3) times the width (w)

44=2w^2 - 3w  distribute

2w^2-3w-44 = 0 subtract 44 from both sides

(w+4)(2w-11) factor

width=11/2

(11/2 x 2) - 3

length = 8

Jared made sixty dollars mowing lawns over the summer. If he spent thirty-nine dollars buying new mower blades, how many seven-dollar games could he buy with the money he had left?

Answers

Answer:

three

Step-by-step explanation:

60 - 39 = 21

21/7 = 3

Answer = 3

60-39
21 divided by 7
3

I need help with number 10 please

Answers

Answer:

Liz

Step-by-step explanation:

if the chart is correct only 3 people spent more than 2 1/2 hours on homework when 9 people spent less than 2 1/2 hours on homework

The present value of $100 to be received 10 years from today, assuming an opportunity cost of 9 percent, is

Answers

An opportunity cost of 9 percent, is $42.

We have given that,

The present value of $100 is to be received 10 years from today,

assuming an opportunity cost of 9 percent,

present value =$100

N=10 years

I/y=9

What is the formula for the present value?

PV= FV/(1+r)^n

Where FV is the future value.

Use the given values in the formula we get,

Therefore the correct answer is 42.

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