An unknown number becomes 30 when rounded to the nearest ten. Which could NOT be the unknown number?
A. 24
B. 25
C. 28
D. 31

Answers

Answer 1

Answer:

A. 24

Step-by-step explanation:

Five and above rounds up

so 25,26,27,28,29 rounds up to 30

We leave it alone when 4 or less

34,33,32,31,30 remains at 30

24 would not round to 30


Related Questions

A random sample of bolts is taken from inventory, and their lengths are measured. The average length in the sample is 5.3 inches with a standard deviation of .2 inches. The sample size was 50. The point estimate for the mean length of all bolts in inventory is

Answers

Answer:

[tex]L_x=5.3 inches[/tex]

Step-by-step explanation:

Average length [tex]\=x =5.3 inches[/tex]

Standard deviation [tex]\sigma=0.2 inches[/tex]

Sample size [tex]n=50[/tex]

Generally The point estimate for the mean length of all bolts in inventory is

[tex]L_x= \=x[/tex]

[tex]L_x=5.3 inches[/tex]

Which type of triangle will always have at least 1-fold reflectional symmetry?

right triangle
obtuse triangle
acute triangle
isosceles triangle

Answers

Answer:

D. isosceles triangle

Step-by-step explanation:

Ed22

A triangle with at least 1-fold reflectional symmetry is isosceles triangle, option D is correct.

What is Triangle?

A triangle is a three-sided polygon that consists of three edges and three vertices.

An isosceles triangle will always have at least 1-fold reflectional symmetry.

This is because an isosceles triangle has two congruent sides and two congruent angles.

If we draw a perpendicular bisector of the base (the side that is not congruent), it will bisect the base and the angle opposite to the base.

This means that the triangle is symmetric with respect to this line of reflection, which is the line of symmetry.

Therefore, the correct answer is isosceles triangle.

To learn more on Triangles click:

https://brainly.com/question/2773823

#SPJ5

How much more area does a large pizza with a 12 in. diameter have than a small pizza with an 8 in. diameter? Round your answer to the nearest square inch.

Answers

Answer: About 63 in²

Step-by-step explanation:

Area of circle = π · r²

r = radius lengthπ ≈ 3.14

Area of large pizza:

[tex]\pi *r^{2} =3.14*6^{2} =3.14*36=113.04[/tex]

Area of small pizza:

[tex]\pi *r^{2} =3.14*4^{2} =3.14*16=50.24[/tex]

Difference in area:

[tex]113.04-50.24=62.8[/tex]

Help me out with these 2 questions for 15 points.

Answers

Step-by-step explanation:

The time dilation formula is given by

[tex]F(t) = \dfrac{t}{\sqrt{1-v^2}}[/tex]

where t is the time measured by the moving observer and F(t) is the time measured by the stationary earth-bound observer and v is the velocity of the moving observer expressed as a fraction of the speed of light.

a) If the observer is moving at 80% of the speed of light and observes an event that lasts for 1 second, a stationary observer will see the same event occurring over a time period of

[tex]F(t) = \dfrac{1\:\text{s}}{\sqrt{1-(0.8)^2}}[/tex]

[tex]\:\:\:\:\:\:\:=\dfrac{1\:\text{s}}{\sqrt{1-(0.8)^2}} =\dfrac{1\:\text{s}}{\sqrt{1-(0.64)}}[/tex]

[tex]\:\:\:\:\:\:\:=1.67\:\text{s}[/tex]

This means that any event observed by this moving observer will be seen by a stationary observer to occur 67% longer.

b) Given:

t = 1 second

F(t) = 2 seconds

We need to find the speed of the observer such that an event seen by this observer will occur twice as long as seen by a stationary observer. Move the term containing the radical to the left side so the equation becomes

[tex]\sqrt{1-v^2} = \dfrac{t}{F(t)}[/tex]

Take the square of both sides, we get

[tex]1 - v^2 =\dfrac{t^2}{F^2(t)}[/tex]

Solving for v, we get

[tex]v^2 = 1 - \dfrac{t^2}{F^2(t)}[/tex]

or

[tex]v = \sqrt{1 - \dfrac{t^2}{F^2(t)}}[/tex]

Putting in the values for t and F(t) we get

[tex]v = \sqrt{1 - \dfrac{(1\:\text{s})^2}{(2\:\text{s})^2}}[/tex]

[tex]v = \sqrt{1 - \dfrac{1}{4}} = \sqrt{0.75}[/tex]

[tex]\:\:\:\:=0.866[/tex]

This means that the observer must moves at 86.6% of the speed of light.

60kg of rice must be put into three equal bags. what weight of rice must be put into each bag?

Answers

Answer:

20kg of rice in each bag

Step-by-step explanation:

we have 60kg of rice and 3 bags. we know that we need to have an eqal amount of rice in each bag so we can divide the 60kgs of rice by 3.

60÷3=20

Checking our Answer:

we can check our work by doing the opposite of division which is multiplication. to check our work we'd have to multiply the dividend (in our case 3) and our quotient (in our case 20) to see if we get the larger dividend (in our case 60) as our answer.

3×20=60


Which one is the intersection point of
f(x) = x3 + 3x and
g(x) = x2 + 3

A) (0,0)
B) (0,3)
C) (1,4)
D) (-1,4)

I URGENTLY NEED HELP PLEASE , I WOULD ALSO MARK AS BRAINLIEST!!

Answers

Answer: C) (1,4)

Step-by-step explanation:

The intersection point is where f(x) = g(x)

x³ + 3x = x² + 3

x³ - x² +3x - 3 = 0

A. (0, 0) → x = 0 → (0)³ - (0)² +3(0) - 3 = -3 ≠ 0B. (0, 3) → x = 0 → (0)³ - (0)² +3(0) - 3 = -3 ≠ 0C. (1, 4) → x = 1 → (1)³ - (1)² +3(1) - 3 = 0 + 0 = 0D. (-1, 4) → x = -1 → (-1)³ - (-1)² +3(-1) - 3 = 0 - 3 - 3 = -6 ≠ 0

Find the perimeter of the figure below, in inches

Answers

Answer:the perimeter is 200.4

Step-by-step explanation: I got this answer by separating the shape into multiple pieces then I added it all together.

what number increased by 130% is 69

Answers

Answer:

The number is 30.

Step-by-step explanation:

Let the number be x

so

x + (130% of x) = 69

x + 13x/10 = 69

or, (10x + 13x)/10 = 69

or, 23x = 690

or, x = 690/23

so, x = 30

Answer: 30

Step-by-step explanation:

its correct on rsm

Land surveyors outlined a park as shown. What is the area of the park?

Answers

la cuadra se llama 6minutos

Which two shapes make up the digital camera below?

Answers

Rectangular prism and cylinder

Rectangular prism and cylinder make up a camera.

What is rectangular prism and cylinder?

A cube is a rectangular prism with all of its sides being the same length, a triangular prism has a triangle as its base, and a rectangular prism has a rectangle as its foundation. Another form of right prism that has a circle as its basis is a cylinder.

A rectangular prism includes a total of 6 faces, 12 sides, and eight vertices. Like a cuboid, it contains three dimensions- the base width, the height, and the length. The top and base of the rectangular prism exist rectangular. The pairs of opposite faces of a rectangular prism exist as identical or congruent.

A cylinder contains traditionally been a three-dimensional solid, one of the most essential curvilinear geometric shapes. Geometrically, it includes been regarded as a prism with a circle as its base.

Hence, Rectangular prism and cylinder make up a camera.

To learn more about rectangular prisms and cylinders refer to:

https://brainly.com/question/15594686

#SPJ2

In an accelerated failure test, components are operated under extreme conditions so that a substantial number will fail in a rather short time. In such a test involving two types of microchips, 580 chips manufactured by an existing process were tested, and 125 of them failed. Then, 780 chips manufactured by a new process were tested, and 130 of them failed. Find a 90% confidence interval for the difference between the proportions of failures for chips manufactured by the two processes. (Round the final answers to four decimal places.) The 90% confidence interval is

Answers

Answer:

The 90% confidence interval is (0.0131, 0.0845).

Step-by-step explanation:

Before finding the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

Old process:

125 out of 580, so:

[tex]p_O = \frac{125}{580} = 0.2155[/tex]

[tex]s_O = \sqrt{\frac{0.2155*0.7845}{580}} = 0.0171[/tex]

New process:

130 out of 780. So

[tex]p_N = \frac{130}{780} = 0.1667[/tex]

[tex]s_N = \sqrt{\frac{0.1667*0.8333}{780}} = 0.0133[/tex]

Distribution of the difference:

[tex]p = p_O - p_N = 0.2155 - 0.1667 = 0.0488[/tex]

[tex]s = \sqrt{s_O^2+s_N^2} = \sqrt{0.0171^2 + 0.0133^2} = 0.0217[/tex]

Confidence interval:

[tex]p \pm zs[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

90% confidence level

So [tex]\alpha = 0.1[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].

The lower bound of the interval is:

[tex]p - zs = 0.0488 - 1.645*0.0217 = 0.0131[/tex]

The upper bound of the interval is:

[tex]p + zs = 0.0488 + 1.645*0.0217 = 0.0845[/tex]

The 90% confidence interval is (0.0131, 0.0845).

Solve the system of equations.
4x + 3y + 5z = 6
6x + 8y + 6z = 4
4x + 2y + z = 8
(x = 1, y = -1,2 = 1)
b. (x = 3, y = -3,2 = 3)
a.
C. (x = 0, y = 0, 2 = 2)
d. (x - 2, y --2, z = 0)

Answers

The answer is x=1 y=-1 and z=1. If you plug in the variables you get
4-3+5 and that equals 6. So that’s the answer

What is the five-number summary for this data set? 22, 29, 33, 38, 44, 47, 51, 56, 64, 69 Assume the numbers in each answer choice are listed in this order: min, Q1, median, Q3, max.
A. 22, 33, 45.5, 56, 69
B. 22, 38, 45.5, 51, 69
C. 22, 38, 41, 51, 69
D. 22, 33, 41, 56, 69​

Answers

Answer: A: 22, 33, 45.5, 56, 59

Step-by-step explanation:

The minimum is the lowest number in the data, in this case, it was 22.

Q1 is the median of the lower quartile range, anything below the median of the overall data.

Median, the middle number in the overall data. You first need to put them from lowest to highest (numerical order). After that, I find it a lot easier to cross one from each side until I'm either left with one or two. If I'm left with one, then that is my median for the overall data set. If I'm left with two, then I simply need to add both the numbers together and divide it by 2. Typically if it is a whole number, and the numbers are 1 number value away from each other, it is usually just 0.5 more of the lower value of the two. (For example, the two numbers I come down to is 10 and 11. The median would be 10.5).

Q3 is the exact same principle as Q1 just on the upper quartile range. Just repeat what you did in Q1 but for the numbers above the overall median of the data set.

Maximum is the highest number in the data set, in this case, it was 69.

Hope this helps!

Find the midpoint of the segment between the points (17, 1) and (-2,8)
a. (15, 9)
b. (-15,-9)
c. (19/2, -7/2)
d. (15/2, 9/2)

Answers

Answer:

Option d

Step-by-step explanation:

(17+(-2))/2 , (8+1)/2

which is,

15/2, 9/2

Answered by GAUTHMATH

15 times a certain number plus 5 times the same number is 80 what is the number​

Answers

x = 4

Every step shown. Once you become used to doing this you will almost be able to do the basic one's in your head without writing much down.

Explanation:

Let the unknown value be  

x

Converting the words into numbers:

First part: "15 times a certain number"  → 15 x

Second part: "plus 5 times the same number" → 15 x + 5 x

The last part: " is 80" ->  15x + 5 x = 80

We are counting  x ' s . 15 of them plus another 5 of them gives a total of 20.

So 15 x + 5 x = 20 x = 80

Divide both sides by 20

20 x ÷ 20 = 80÷ 20

20/20x=80/20

x=4

Let the number be x

ATQ

[tex]\\ \sf\longmapsto 15x+5x=80[/tex]

[tex]\\ \sf\longmapsto (15+5)x=80[/tex]

[tex]\\ \sf\longmapsto 20x=80[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{80}{20}[/tex]

[tex]\\ \sf\longmapsto x=4[/tex]

Identify the pair numbers

Answers

Answer:

D. 212 degrees Fahrenheit and 100 degrees Celsius.

Step-by-step explanation:

The boiling point of water in Celsius is 100.

The way to calculate Celsius to Fahrenheit:

F = (C × 9/5) + 32

So we plug in 100 for C.

F = (100 × 9/5) + 32

F = 180 + 32

F = 212

Therefore, the numbered pair is 212 degrees F and 100 degrees  C.

For the z test, the critical region for rejection of H0 _________. Group of answer choices depends on N is determined only by alpha and N allows us to accept the null hypothesis is determined only by alpha

Answers

Answer:

allows us to accept the null hypothesis

Explanation:

The z test(in a normal distribution) score for the critical region determines whether we reject the null hypothesis(H0) or accept the null hypothesis(reject or fail to reject the null hypothesis). If we fail to reject the null hypothesis, then we have accepted the alternative hypothesis (H1). The critical region rejection for z test is calculated using alpha and z score, if z score is greater or less than alpha(positive or negative), we reject the null hypothesis.

A force of 18 lb is required to hold a spring stretched 8 in. beyond its natural length. How much work W is done in stretching it from its natural length to 10 in. beyond its natural length

Answers

Answer: 18.75 lb.ft

Step-by-step explanation:

Given

Force required to stretch spring 8 in. is 18 lb

it can be written

[tex]\Rightarrow F=kx\\\Rightarrow 18=k(8)\\\\\Rightarrow k=\dfrac{18}{8}=\dfrac{9}{2}\ lb/in.[/tex]

Work done in stretching from its natural length to 10 in.

[tex]\Rightarrow W=\dfrac{1}{2}kx^2\\\\\Rightarrow W=0.5\times \dfrac{9}{2}\times (10)^2\\\\\Rightarrow W=225\ lb.in.\ or\\\Rightarrow W=18.75\ lb.ft[/tex]

find the missing side length in the image below

Answers

Let missing side be x

Using basic proportionality theorem

[tex]\\ \sf\longmapsto \dfrac{18}{14}=\dfrac{27}{x}[/tex]

[tex]\\ \sf\longmapsto \dfrac{9}{7}=\dfrac{27}{x}[/tex]

[tex]\\ \sf\longmapsto 9x=7(27)[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{7(27)}{9}[/tex]

[tex]\\ \sf\longmapsto x=21[/tex]

The slide is inclined at an angle of 52.0°. Danny weighs 46.0 pounds. He is sitting in a cardboard box
with a piece of wax paper on the bottom. Stacey is at the top of the slide holding on to the cardboard
box. Find the magnitude of the force Stacey must pull with, in order to keep Danny from sliding down
the slide. (We are assuming that the wax paper makes the slide into a frictionless surface, so that the
only force keeping Danny from sliding is the force with which Stacey pulls.)

Answers

Answer:

Step-by-step explanation:

Since the slide is inclined at an angle of 52.0° to the horizontal, Danny's weight (mass, m) of 46.0 pounds has a component W = mgcos52.0° perpendicular to the incline and W' = mgsin52.0° parallel to the incline where g = acceleration due to gravity = 32 ft/s²

The perpendicular component of Danny's weight is the normal force to the incline. This normal force would determine the magnitude of the friction along the incline.

Since the wax paper makes the incline surface frictionless, so, there is no friction along the surface and thus the only horizontal force acting along the surface is the component of Danny's weight along the surface.

For Stacey to keep Danny from sliding down along the incline, the force she applies along the incline, F must be equal to the component of Danny's weight along the incline.

So, F = W'

F = mgsin52.0°

F = 46lb × 32 ft/s² × sin52°

F = 1472 lb-ft/s² 0.7880

F = 1159.95 lb-f

F ≅ 1160 lb-f

Mr. Montes is writing a short, three-question, true or false quiz for his Algebra 2 classes. He had planned on using a random answer generator to determine which of true or false would be the correct answer for each quiz question, but his internet is not working. Instead, he writes each possible answer combination on a small slip of paper, folds each paper in half, and then places them in a box. Without looking, he draws one of the slips of paper.
Use what you know about counting methods and set operations to answer the following questions.
After grading the quizzes, Mr. Montes decides that his students could use some additional practice with the concepts tested. He writes a take-home assignment for his students. The assignment starts with two true or false questions and then has 3 multiple choice questions. The multiple choice questions each have 4 answer options, only 1 of which is correct. Luckily, Mr. Montes’ internet is working when he writes the quiz and he is able to use a random answer generator.
After grading the take-home assignments, Mr. Montes randomly selects 5 take-home assignments to analyze. He considers the student’s responses to the three multiple choice questions, which are as shown.
Student 1: Student 2: Student 3: Student 4: Student 5:
{C, A, C} {C, B, B} {C, B, C} {C, B, A} {C, A, A}
Amisha was too tired to work on the take home assignment Mr. Montes gave her, so she randomly selected answers without reading any of the questions. Suppose that you wanted to find the odds that Amisha answered at least 3 of the 5 questions correctly. Do you think you would use a permutation or a combination?
1. The correct responses for the multiple choice questions are, in order, C, B, and A. If Set 1 represents the subset of these students who answered C for number 1, Set 2 represents the subset of these students who answered B for number 2, and Set 3 represents the subset of students who answered A for number 3, find each of the following. Explain what each notation means in context of this scenario.
a. Set 1 ∩ Set 2
b. Set 2 ∪ Set 3
c. The complement of Set 1
2. Amisha was too tired to work on the take home assignment Mr. Montes gave her, so she randomly selected answers without reading any of the questions. Suppose that you wanted to find the odds that Amisha answered at least 3 of the 5 questions correctly. Do you think you would use a permutation or a combination?

Answers

Answer:

There are 4 questions to answer here and the answers are given below:

1. COMBINATION

2. SET 2  

3. {S2, S3, S4, S5}

4. { }  OR  ∅

Step-by-step explanation:

The key topics here are PERMUTATION & COMBINATION and SETS & VENN DIAGRAMS.

The assignment has 5 questions in all. The options for each question are listed below and separated by commas:

1. True, False

2. True, False

3. A, B, C, D

4. A, B, C, D

5. A, B, C, D

Mr. Montes derives his answers from a random answer generator; same way Amisha generated her answers by random selection.

QUESTION 1

If you want to find the odds that Amisha got at least 3/5 of the answers correctly, would you use a permutation or a combination?

ANSWER TO QUESTION 1

You would use a combination. Note that as much as 'permutation' is distinctly defined from 'combination', in many complex cases both are used to derive the solution. In this case though, a combination is used. For each of the 5 questions, there are a number of possible answers. Questions 1 and 2 have only two possible answers (also known as options) while questions 3, 4 and 5 have four possible answers/options to choose from. Amisha can only have one set of five answers; each to each question. So this is a combination! If you want to find the odds that Amisha got at least 3 of her 5 answers correct, you would use a combination of the various possible answers to check.

QUESTION 2

Find "Set 1 ∩ Set 2" and explain the notation in the sentence.

ANSWER TO QUESTION 2

First list out relevant information:

- The correct answers to questions 3, 4 and 5 are respectively C, B, A

- The universal set consists of five students: S1, S2, S3, S4, S5 hence

Ц = {S1, S2, S3, S4, S5}

Next, enlist the elements of each defined set

Set 1: {S1, S2, S3, S4, S5}     Set 2: {S2, S3, S4}     Set 3: {S4, S5}

Note: Set 1 is equal to the universal set.

Now this notation "∩" means "intersect". It requires an action - checking out which elements in one set also appear in a second set and then bringing those elements to form a new set.

In the case of this question, we're to find Set 1 intersect Set 2. The elements present in Set 1 and also present in Set 2 are {S2, S3, S4}.

If you look closely, you'll observe that these are the same elements in Set 2! This brings to remembrance, one of the laws of sets:

The intersect of any subset and the universal set (recall that Set 1 happens to be equal to or have the same elements as the universal set) is equal to that subset.

So the answer to question 2 is

Set 1 ∩ Set 2 = Set 2

QUESTION 3

Find "Set 2 ∪ Set 3" and explain the notation in the sentence.

ANSWER TO QUESTION 3

The notation ∪ represents "union". This is the act of putting together the elements in two sets, to form a new set. In this activity, if an element appears in both sets, it is only written once in the new set, not twice.

So, Set 2 union Set 3 = {S2, S3, S4, S5}

As earlier stated, Student 4 isn't appearing twice in the new set.

QUESTION 4

Find the ' of Set 1 and explain the notation in this sentence.

ANSWER TO QUESTION 4

The symbol ' means "complement of a set". Finding the complement of a set is like subtracting the elements of that set from the universal set.

Since Set 1 contains the same elements as the universal set, subtracting Set 1 from the universal set will give you nothing. In this case, the complement of Set 1 is a null set!

Set 1 ' Ц = { }  or  ∅

where the empty bracket symbol and the slashed zero symbol represent null set.

Kudos!

Find the area of the circle. Use 3.14 for it. E d = 10 cm A = [?] cm2 A=7tr2​

Answers

Answer:

A=(78.5)cm²

Step-by-step explanation:

d=10

r=10/2=5

A=πr²

A=3.14*5²

A=3.14*25

A=78.5cm²

Answer: d=10cm

According to the formula i.e. A=πr²

first we need 'r'

as r=d/2

hence,  r= 10cm/2

r=5cm

put r=5 in formula

=3.14(5cm)²

=3.14×25cm²

=78.5cm²

WILL MARK BRAINLYST!!! Enter the correct answer in the box. Write your answer in the form y=mx+ b, using the appropriate inequality symbol in place of the equal sign.
What inequality is shown in the graph?

Answers

Answer:

The inequality shown in the graphic is [tex]y > 4x + 1[/tex]

Step-by-step explanation:

Equation of a line:

The equation of a line is given by:

[tex]y = mx + b[/tex]

In which m is the slope and b is the y-intercept(value of y when x = 0).

Inequality:

Values greater than the dashed line, dashed so the line is not part of the inequality, thus, the inequality is:

[tex]y > mx + b[/tex]

Dashed line:

The dashed line goes through (0,1) and (1,5).

Point (0,1) means that when [tex]x = 0, y = 1[/tex], so [tex]b = 1[/tex], and:

[tex]y > mx + 1[/tex]

Finding the slope:

When we have two points, the slope is given by the change in y divided by the change in x. In this question, we have point (0,1) and (1,5), so:

Change in y: 5 - 1 = 4

Change in x: 1 - 0 = 1

Slope: [tex]m = \frac{4}{1} = 4[/tex]

What inequality is shown in the graph?

[tex]y > 4x + 1[/tex]

identify an equation in point slope form for the line perpendicular to y=5x=2 that passes through (-6,-1)

Answers

Answer:

y=-1/5x-11/5

Step-by-step explanation:

perpendicular, product of both gradients = -1

hence, slope = -1/5

y=-1/5x+c

sub y=-1, x=-6

-1=-1/5(-6)+c

c = -1-6/5=-11/5

y=-1/5x-11/5

write the expression as a trinomial (5c+2)(2c-1)

Answers

Answer:

10c^2-c-2

Step-by-step explanation:

FOIL method

or just multiply all of the numbers by each other, if you get 4 numbers you did it right then simplify;

(5c+2)(2c-1) 5c*2c; 2*-1; -1*5c; 2*2c = 10c^2, -2, -5c, 4c, simplify, 10c^2 -c -2. Hope this helps :)

Answer:

10c² - c - 2

Step-by-step explanation:

(5c+2)(2c-1)

10c² - 5c + 4c - 2

10c² - c - 2

A person's email for one day contained a total of 78 messages. The number of spam
messages was two less than four times the number of other messages. How many of
the email messages were spam?

Answers

Answer:

62 of the email messages were spam

Step-by-step explanation:

Let the number of spam and other messages be s and o respectively.

Total number of messages= 78

s +o= 78 -----(1)

s= 4o -2 -----(2)

Substitute (2) into (1):

4o -2 +o= 78

Simplify:

5o -2= 78

+2 on both sides:

5o= 78 +2

5o= 80

Divide both sides by 5:

o= 80 ÷5

o= 16

Since s +o= 78, s= 78 -o.

s= 78 -16

s= 62

An education researcher would like to test whether 2nd graders retain or lose knowledge during the summer when they are presumably not in school. She asks nine 2nd graders to take a comprehension exam at the end of the school year (May), and then asks those same students to come back after the summer (late August) to retake a different but equivalent exam, to see if their level of comprehension has changed. Using the data below, test this hypothesis using an (alpha level of 0.05.)

May August
95 100
72 80
78 95
50 65
89 85
92 98
75 70
90 96
65 87

Required:
What is the appropirate test?

Answers

Answer:

Kindly check explanation

Step-by-step explanation:

Given the data:

May August

95 100

72 80

78 95

50 65

89 85

92 98

75 70

90 96

65 87

The appropriate test is a paired t test :

d = difference between May and August

d = (-5, -8, -17, -15, 4, -6, 5, -6, -22)

The hypothesis :

H0 : μd = 0

H1 : μd ≠ 0

The test statistic :

T = dbar / (Sdbar/√n)

Where, dbar and Sdbar are the mean and standard deviation of 'd' respectively.

Using calculator :

dbar = - 7.777 ; Sdbar = 9.052

Test statistic = - 7.777 / (9.052 /√9)

Test statistic = - 2.577

The Pvalue, df = n - 1 = 9 - 1 = 8

Pvalue(-2.577, 8) = 0.0327

At α = 0.05

Pvalue < α ; WE reject the H0 ; and conclude that there has been a change in score

Find the most general antiderivative of the function. (Check your answer by differentiation. Use C for the constant of the antiderivative. Remember to use absolute values where appropriate.)
f(x) = 45−5x, x>0 .

Answers

Answer:

F(x) = 45*x - (5/2)*x^2 + C

Step-by-step explanation:

Here we want to find the antiderivative of the function:

f(x) = 45 - 5*x

Remember the general rule that, for a given function:

g(x) = a*x^n

the antiderivative is:

G(x) = (a/(n + 1))*a*x^(n + 1) + C

where C is a constant.

Then for the case of f(x) we have:

F(x) = (45/1)*x^1 - (5/2)*x^2 + C

F(x) = 45*x - (5/2)*x^2 + C

Now if we derivate this, we get:

dF(x)/dx = 1*45*x^0 - 2*(5/2)*x

dF(x)/dx = 45 - 5*x

Simplify: –3(y + 2)2 – 5 + 6y.

Answers

Answer:

-17

Step-by-step explanation:

–3(y + 2)2 – 5 + 6y

(–3y -6)2 – 5 + 6y

-6y -12 - 5 + 6y

-17

Please helps fill in the charts
A and b
With order of pairs

Answers

Answer:

...

Step-by-step explanation:

seeee the above picture

Other Questions
In general, rsums need to have at least three mains sections. Which of the following is NOT one of these sections?referencescurrent and past job historyname and contact informationposthigh school educational achievements Do you think that interest and capacity play a great role to get success in a profession?Give your opinion. -3 (x -4/3) < 6pls help me pls help me is important to the transmission of nerve impulses.a) Zincb) Calciumc) Sodiumd) IronPlease help thx The sum of 2 consecutive integers 117 what are the integers how do i say (can i order?) in Spanish Entries for Discounted Note Payable A business issued a 90-day note for $57,000 to a creditor on account. The note was discounted at 8%. Assume a 360-day year. a. Journalize the entry to record the issuance of the note. For a compound transaction, if an amount box does not require an entry, leave it blank. If necessary, round to one decimal place. Accounting numeric field b. Journalize the entry to record the payment of the note at maturity. Explain the digestion in amoeba An airplane started at 0 feet. It rose 21,000 feet at takeoff. It then descended 4,329 feet because of clouds. An oncoming plane was approaching, so it rose 6,333 feet. After the oncoming plane passed, it descended 8,453 feet, at what altitude was the plane flying? geosphere burying organisms hydrosphere respiration of marine lifebiosphere photosynthesis atmosphere burning things How economy and imperialism are similar? Find the domain and range of the function, f(x)=sin|x| Which statement best describes how forces are important to chemistry?A. Forces are transferred when atoms form ions.B. Forces are released during chemical reactions.C. Forces determine the extent of a reaction.D. Forces hold atoms and molecules together. What do you understand by moment of inertia and torque?Word limit 50-60Please don't copy from any sources. You can rewrite. Plagiarism will be check. Thank you. Dnde trabaja el seor Loisel Plane P is a cross-section of the solid below. What shape is the cross section?A. rectangleB. not enough informationC. hexagonD. pentagon Megan and Suzanne each have a plant. They track the growth of their plants for four weeks.Whose plant grew at a faster rate, and what was the rate?Suzannes at 2 inches per weekSuzannes at 1.5 inches per weekMegans at 3 inches per weekMegans at 2.5 inches per week a.3. Suffocation is:the loss of memory and thinking and reasoning abilities.b. a sudden event in which people are killed and injured.when breathing stops from the lack of oxygen.d. when electrical current passes through the body.C. Economists assume that individual decisions will be determined by the output or production costs they create. the output or production costs they create. the trade-offs they creates. the trade-offs they creates. the societal demands associated with them. Would/ Should he go school tomorrow, he will give me this book.