The dotplots below display the scores for two classes on a 30-point statistics quiz. Class A has 26 students and Class B has 25 students.

2 dot plots. For Class A, the dots are spread out more. For Class B, the dots are more grouped together.

Which statement best compares the variability of the quiz scores for Class A and Class B?

The scores on the quiz for Class A have more variability than the scores for Class B.
The scores on the quiz for Class B have more variability than the scores for Class A.
The scores on the quiz for Class A have less variability than the scores for Class B.
The scores on the quiz for Class B have about the same variability as the scores for Class A.

I think its (A), The scores on the quiz for Class A have more variability than the scores for Class B. Can someone check me?

Answer:

[tex]x = 2[/tex]

[tex]S_n = 63[/tex]

Step-by-step explanation:

Given

[tex]a_1 = x + 1[/tex]

[tex]a_2 = 4x -2[/tex]

[tex]a_3 = 6x -3[/tex]

[tex]a_n = 18[/tex]

Solving (a): x

To do this, we make use of common difference (d)

[tex]d = a_2 - a_1[/tex]

[tex]d = a_3 - a_2[/tex]

So, we have:

[tex]a_3 - a_2 = a_2 - a_1[/tex]

Substitute known values

[tex](6x - 3) - (4x - 2) = (4x - 2) - (x + 1)[/tex]

Remove brackets

[tex]6x - 3 - 4x + 2 = 4x - 2 - x - 1[/tex]

Collect like terms

[tex]6x - 4x- 3 + 2 = 4x - x- 2 - 1[/tex]

[tex]2x- 1 = 3x- 3[/tex]

Collect like terms

[tex]2x - 3x = 1 - 3[/tex]

[tex]-x = -2[/tex]

[tex]x = 2[/tex]

Solving (b): Sum of progression

First, we calculate the first term

[tex]a_1 = x + 1[/tex]

[tex]a_1 = 2 + 1 = 3[/tex]

Next, calculate d

[tex]d = a_2 - a_1[/tex]

[tex]d = (4x - 2) - (x +1)[/tex]

[tex]d = (4*2 - 2) - (2 +1)[/tex]

[tex]d = 6 - 3 = 3[/tex]

Next, we calculate n using:

[tex]a_n = a + (n - 1)d[/tex]

Where:

[tex]a_n = 18[/tex]

[tex]d = 3; a = 3[/tex]

So:

[tex]18 = 3 +(n - 1) * 3[/tex]

Subtract 3 from both sides

[tex]15 = (n - 1) * 3[/tex]

Divide both sides by 3

[tex]5 = n - 1[/tex]

Add 1 to both sides

[tex]6 = n[/tex]

[tex]n = 6[/tex]

The sum of the progression is:

[tex]S_n = \frac{n}{2} * [a + a_n][/tex]

So,, we have:

[tex]S_n = \frac{6}{2} * [3 + 18][/tex]

[tex]S_n = 3 * 21[/tex]

[tex]S_n = 63[/tex]

Answer:

The answer is that the runner can run 10 miles in 70 minutes.

Step-by-step explanation:

To solve for the number of miles that the runner can run in 70 minutes, start by setting up the information given from the problem in the form of a proportion.

A proportion is an equation which defines that the two given ratios are equivalent to each other. In other words, the proportion states the equality of the two fractions or the ratios. In a proportion, if two sets of given numbers are increasing or decreasing in the same ratio, then the ratios are said to be directly proportional to each other.

The proportion for this problem will look like [tex]\frac{2 miles}{14 minutes}=\frac{x}{70 minutes}[/tex]. (x) will be used as the variable for the number of miles that the runner can run in 70 minutes.  

To solve the proportion, start by cross multiplying to form an equation, and the equation will look like [tex](14)(x)=(2)(70)[/tex]. Next, simplify the equation, which will look like [tex](14)(x)=140[/tex]. Then, solve the equation by dividing both sides of the equation by 14, and it will look like [tex]x=10[/tex]. The final answer is that the runner can run 10 miles in 70 minutes.

Answer:

You dind't include the answer choices but it should look something like

[tex]50000(.8)^t[/tex]

Answer:

-1/3

Step-by-step explanation:

Perpendicular lines have slopes that multiply to -1

a*b = -1

3 * b = -1

b = -1/3

The slope of line b is -1/3

Explanation:

A = values on the die greater than 1

A = {2,3,4,5,6}

B = values on the die less than 5

B = {1,2,3,4}

Union those two sets together

C = A u B = {1,2,3,4,5,6}

Effectively, we get every possible value on the die. This is due to the "or" keyword. If it was "and", then it would be a difference story.

So the probability of getting anything in set C is 100% or just 1. We have guaranteed certainty we'll have this event happen.

Answer:

Option b, (4,2)

Option d, (8,4)

Option e, (12,6)

Answered by GAUTHMATH

Answer:

Option b, (4,2)

Option d, (8,4)

Option e, (12,6)

Step-by-step explanation:

the person above me is correct

( x + 1 )( x )( x - 5 ) =

( x + 1 )( x - 5 )( x ) =

( x^2 - 4x - 5 )( x ) =

x^3 - 4x^2 - 5x

Step-by-step explanation:

the other answer is basically correct.

as the simplest form you create 3 terms for the three given solutions (= the values for when the equation equals 0).

but maybe you need to add " = 0" for the full equation.

Answer: y = 0 and x = -1

Answer:

27 inch

Step-by-step explanation:

Current perimeter=18

New perimeter=18*1.5=27 in

Answer:

9/49

Step-by-step explanation:

that is the procedure above

Answer:

Between 79.2 and 84.8.

Step-by-step explanation:

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

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

Approximately 95% of the measures are within 2 standard deviations of the mean.

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

In this problem, we have that:

Mean of 82, standard deviation of 2.8.

In what range would you expect to find the FBG of 68% of your study participants?

By the Empirical Rule, within 1 standard deviation of the mean, so:

82 - 2.8 = 79.2

82 + 2.8 = 84.8

Between 79.2 and 84.8.

Taking into account the definition of axis of simmetry and vertexn the axis of symmetry is x = 5.

So, first of all, you must know what a quadratic function is. Every quadratic function can be expressed as follows:

f(x) = a*x² + b*x + c

where a, b and c are real numbers.

The graph of a quadratic function is a parabola. Every parabola is a symmetric curve with respect to a horizontal line called the axis of symmetry.

That is, the axis of symmetry is an imaginary line that passes through the middle of the parabola and divides it into two halves that are equal of each other.

In other words, the axis of symmetry of a parabola is a vertical line that divides the parabola into two equal halves and always passes through the vertex of the parabola.

The point of intersection of the axis of symmetry with the parabola is called the vertex.

The axis of symmetry always passes through the vertex of the parabola. The x-coordinate of the vertex is the equation of the axis of symmetry of the parabola.

Being the vertex of the quadratic function (5,7), where the vertex on the x-axis has a value of 5 and on the y-axis a value of 7, the axis of symmetry is x = 5.

Learn more with this examples:

Answer:

(483.981 ; 504.019)

Step-by-step explanation:

Given :

σ = 100

Sample size, n = 661

xbar = 494

We use the Z distribution since we are working with the population standard deviation ;

C.I = xbar ± (Zcritical * σ/√n)

Zcritical at 99% = 2.576

C.I = 494 ± (2.576 * 100/√661)

C.I = 494 ± 10.019

Lower boundary = (494−10.019) = 483.981

Upper boundary = (494+10.019) = 504.019

C.I = (483.981 ; 504.019)

Answer:

X-(-7)

Step-by-step explanation:

If you are subtract by a negative number it turns it into a positive. It would look like this: X+(+7)

Answer:

x = 65

Step-by-step explanation:

x = √(25×(25+144))

x = √(25×169)

x = 5×13

x = 65

Answered by GAUTHMATH

The LEAST selling price of the laptop should be ;

$1024.1 in other to avoid loss.

Price of laptop = $770

Tax = 20%

VAT = 13%

TO avoid loss ;

both the VAT percentage and TAX must be added to the price of the laptop:

Total percentage = VAT + TAX = (20 + 13) = 33%

THEREFORE, Least selling price should be :

Price of laptop * (1 + 33%)

770 * 1.33

= $1024.1

Learn more about TAX :

https://brainly.in/question/31818297

Answer:

Angle T is congruent to Angle Z

Step-by-step explanation:

Since the 2 triangles are equal, that means that each pair of angles are also congruent. To know which angles are congruent, you check th order of how the triangles are named. Ex. Angle Q is congruent to Angle A, Angle P is congruent to Angle R, and Angle T is congruent to Angle Z.

Answer: The area is 22 17/64.

Step-by-step explanation:

base = 7 1/8 = 57/8

height = 6 1/4 = 25/4

area = 1/2*b*h

= 1/2*57/8*25/4

= 1425/64

= 22 17/64

Answer:

0.25

Step-by-step explanation:

16/4 = 4

4/4 = 1

1/4 = 0.25

0.25/4 = 0.0625

0.0625/4 = 0.015625

give me brainliest please:)

Answer:

There are 666 numbers multiple of 3 in the interval.

Step-by-step explanation:

Multiples of 3:

A number is a multiple of 3 if the sum of it's digits is a multiple of 3.

Range [2,2000]:

First multiple of 3 in the interval: 3

Last: 1998

How many:

[tex]1 + \frac{1998 - 3}{3} = 1 + 665 = 666[/tex]

There are 666 numbers multiple of 3 in the interval.

Answer:

x = -5/2 y +25/2

Step-by-step explanation:

5y + 2x = 25

Subtract 5y from each side

5y + 2x -5y= -5y+25

2x = -5y +25

Divide by 2

2x/2 = -5y/2 +25/2

x = -5/2 y +25/2

Answer:

1,000 defects

Step-by-step explanation:

Find how many defects that should be made by finding 1% of 100,000:

100,000(0.01)

= 1000

So, there should be 1,000 defects

Answer:

$3792116

Step-by-step explanation:

that's the answer above

Answer:

Each group has 1 fiction book and 2 nonfiction book(s).

Answer:

972pi in ^3

Step-by-step explanation:

We need to find the volume of the sphere

V = 4/3 pi r^3

The diameter is 18

r = d/2 = 18/2 = 9

V = 4/3 pi ( 9)^3

V = 972pi in ^3

Answer:

Step-by-step explanation:

Speed = (15 mi)/hr × (1.6 km)/mi = (24 km)/hr

:::::

(4 hr) × (24 km)/hr = 96 km

Answer:

The minimum sample size is 1,704.

Step-by-step explanation:

We have to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:

[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]

Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].

That is z with a p-value of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.

Now, find the margin of error M as such

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.

Standard deviation of 21,059,637 shares

This means that [tex]\sigma = 21059637[/tex]

What is the minimum required sample size if you would like your sampling error to be limited to 1,000,000 shares?

This is n for which [tex]M = 1000000[/tex], so:

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

[tex]1000000 = 1.96\frac{21059637}{\sqrt{n}}[/tex]

[tex]1000000\sqrt{n} = 1.96*21059637[/tex]

[tex]\sqrt{n} = \frac{1.96*21059637}{1000000}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.96*21059637}{1000000})^2[/tex]

[tex]n = 1703.8[/tex]

Rounding up:

The minimum sample size is 1,704.

Answer:

diện tích đa giác trong hình là :

186 cm2

Step-by-step explanation:

hãy tách hình đa giác trên thành 4 hình chữ nhật và tính diện tích từng hình chữ nhật

Answer:

0.6524 = 65.24% probability that the runner will average between 146 and 150 minutes in these 49 marathons.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

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

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.

Average of 147 minutes with a standard deviation of 12 minutes.

This means that [tex]\mu = 147, \sigma = 12[/tex]

Consider 49 of the races.

This means that [tex]n = 49, s = \frac{12}{\sqrt{49}} = \frac{12}{7} = 1.7143[/tex]

Find the probability that the runner will average between 146 and 150 minutes in these 49 marathons.

This is the p-value of Z when X = 150 subtracted by the p-value of Z when X = 146. So

X = 150

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

By the Central Limit Theorem

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

[tex]Z = \frac{150 - 147}{1.7143}[/tex]

[tex]Z = 1.75[/tex]

[tex]Z = 1.75[/tex] has a p-value of 0.9599

X = 146

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

[tex]Z = \frac{146 - 147}{1.7143}[/tex]

[tex]Z = -0.583[/tex]

[tex]Z = -0.583[/tex] has a p-value of 0.3075.

0.9599 - 0.3075 = 0.6524.

0.6524 = 65.24% probability that the runner will average between 146 and 150 minutes in these 49 marathons.

Answer:

The 95% confidence interval for the mean of mid-upper arm circumference based on your sample is between 139.29 mm and 160.71 mm.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom,which is the sample size subtracted by 1. So

df = 4 - 1 = 3

90% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 3 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 3.1824

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 3.1824\frac{6.73}{\sqrt{4}} = 10.71[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 150 - 10.71 = 139.29 mm

The upper end of the interval is the sample mean added to M. So it is 150 + 10.71 = 160.71 mm

The 95% confidence interval for the mean of mid-upper arm circumference based on your sample is between 139.29 mm and 160.71 mm.