Could anyone help me please?

Try this option, the answer is marked with red colour.

Answer:

Correct choice is B

Answer:

51 DVDs

Step-by-step explanation:

Let the number of DVDs and CDs sold be x each.

Initial

Number of DVDs= 86

Number of CDs= 52

After selling

Number of DVDs= 86 -x

Number of CDs= 52 -x

Given that there are 3 times as many DVDs than CDs left,

86 -x= 3(52 -x)

Expand:

86 -x= 156 -3x

Bring x terms to 1 side, constant to the other:

3x -x= 156 -86

Simplify:

2x= 70

Divide both sides by 2:

x= 35

Amount of DVDs left

= 86 -x

= 86 -35

= 51

Answer:

Step-by-step explanation:

1 in 5 = 1/5 = 20% that he wins

Probability that he will NOT win

= 1 - 20%

= 100% -20%

= 80%

Answer:

80%

Step-by-step explanation:

percentage of winning

1/5×100%=20%

percentage of not winning

100%_20%=80%

Answer:

False

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.

Population:

[tex]\mu = 30, \sigma = 8[/tex]

Sample of 4

This means that [tex]n = 4, s = \frac{8}{\sqrt{4}} = 4[/tex]

Probability of obtaining a sample mean greater than 34:

This is 1 subtracted by the p-value of Z when X = 34. So

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

By the Central Limit Theorem

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

[tex]Z = \frac{34 - 30}{4}[/tex]

[tex]Z = 1[/tex]

Thus, the probability of obtaining a sample mean greater than 34 is equal to the probability of obtaining a z-score greater than z = 1.00, and the statement in this question is false.

The "x-interept" is the point where the graph crosses the x-axis.

From here, it looks like this graph crosses the x-axis where x=2 .

So the point is  (2, 0) .

That's choice-A .

Answer:

195.6

Step-by-step explanation:

The general formula for the total surface area of a regular pyramid is T. S. A. =12pl+B where p represents the perimeter of the base, l the slant height and B the area of the base.

Answer:

[tex]\frac{x}{y}[/tex]

Step-by-step explanation:

There you go.

Answer: The quotient of x is invisible number it can be any number depending of the equation

Answer:

See image below:)

Step-by-step explanation:

Answer:

[tex]H_o:\mu = 395000[/tex]

[tex]H_a:\mu < 395000[/tex]

Step-by-step explanation:

Given

[tex]\mu = 395000[/tex] -- mean price

Required

Determine the null and alternate hypotheses

From the question, we understand that the mean price is:

[tex]\mu = 395000[/tex]

This represents the null hypothesis

[tex]H_o:\mu = 395000[/tex]

The belief that the home prices are lower represents the alternate hypothesis

Lower means less than

So, the alternate hypothesis is:

[tex]H_a:\mu < 395000[/tex]

Complete Question

A polling agency conducted a survey about social media in which each person in random samples of 1,000 men and 1,000 women was asked what factor he or she considers to be the most important when deciding whether to connect on social media with another person. The responses are shown in the table

Factor

Personal Friend,Stay in Touch,Mutual Friends,Business Networking Other

Men           600 210 106 45 40

Women      650 224 65 15  46

What is the contribution to the chi square test statistic for men who selected business networking as the most important factor ?

a. 0.5

b. 5

c. 7.5

d. 30

e. 45

Answer:

Correct option is C

Step-by-step explanation:

From the question we are told that:

Sample

[tex]n =1,000 men+ 1,000 women[/tex]

Factor  Table

Personal Friend,Stay in Touch,Mutual Friends,Business, Networking Other

Men           600 210 105 45 40

Women      650 224 65 15  46

Generally the equation for Expected value for Men, Business and networking X is mathematically given by

[tex]X= \frac{Row Total * Column Total}{Grand Total}[/tex]

[tex]X=\frac{(600 + 210 + 105 + 45 + 40)*(45 + 15)}{(600 + 210 + 105 + 45 + 40 + 650 + 224 + 65 + 15 + 46)}[/tex]

[tex]X=30.015[/tex]

Generally the equation for Chi Contribution is mathematically given by

[tex]Y= {(45 - 30.015)^2}{30.015}[/tex]

[tex]Y=7.48[/tex]

[tex]Y \approx 7.5[/tex]

Therefore

Correct option is C

The contribution to the chi square test statistic for men who selected business networking as the most important factor is 7.5

The expected value is calculated as:

[tex]X = \frac{RT * CT}{GT}[/tex]

Where:

RT represents the row total, CT represents the column total and GT represents the grand total.

For Men, Business and networking, we have:

[tex]X = \frac{(600+ 210 +105+45 + 40) * (45 + 15)}{(600 +210 +105 +45 +40 +650 +224 +65 +15 +46)}[/tex]

Evaluate the sum

[tex]X = \frac{1000 * 60}{2000}[/tex]

[tex]X = 30[/tex]

The contribution to the chi square test statistic for men who selected business networking is then calculated as:

Y = (Business Networking - X)^2 / X

This gives

[tex]Y = \frac{(45 - 30)^2}{30}[/tex]

Evaluate the difference

[tex]Y = \frac{15^2}{30}[/tex]

Evaluate the exponent

[tex]Y = \frac{225}{30}[/tex]

Evaluate the quotient

[tex]Y = 7.5[/tex]

Hence,  the contribution to the chi square test statistic for men who selected business networking as the most important factor is 7.5

Read more about chi square test statistic at:

https://brainly.com/question/19959558

Answer:

13.50=1.50+.6x

Step-by-step explanation:

13.50=1.50+ .6x

12=.6x

20=x

The value of the equation is 13.50 = 1.50 + 0.6m , where y is the total cost and x is the number of miles traveled and m = 20 miles

Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.

It demonstrates the equality of the relationship between the expressions printed on the left and right sides.

Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.

Given data ,

Let the equation be represented as A

Now , the value of A is

Substituting the values in the equation , we get

Let the total cost of the taxi be represented as y

Let the number of miles traveled be represented as m

Now , the total cost = $ 13.50

The number of miles = m miles

The initial cost of taxi = $ 1.50

The cost per mile = $ 0.60

So , the equation is 13.50 = 1.50 + 0.6m

Subtracting 1.50 , we get

12 = 0.6m

Divide by 0.6 , we get

m = 20 miles

Hence , the number of miles is 20 miles

To learn more about equations click :

https://brainly.com/question/19297665

#SPJ2

Answer:

B

Step-by-step explanation:

20,24,25,27,29,31,34

min = 20

Q1 = 24

median = 27

Q3 = 31

max = 34

============================================================

Explanation:

Original Data Set = {29, 31, 27, 20, 25, 34, 24}

Sorted Data Set = {20, 24, 25, 27, 29, 31, 34}

The middle-most value of the sorted set is 27, since there are 3 values above it and 3 values below. So the median is 27.

The median is represented by the vertical line inside the box. It does not have to be at the visual midpoint between the left and right edges. It simply needs to be anywhere inside the box.

So we can rule out choice B for instance because this answer choice shows a median of 25, when we want 27 instead.

Choices A, C and D all have the same median of 27.

-------------

Break up the sorted set into two smaller sets like this

L = {20, 24, 25}

U = {29, 31, 34}

L represents the set of lower values, which are smaller than the median. U is the upper set of values larger than the median. The median itself is not in L or U.

Find the median of L and U to get 24 and 31 respectively. These are the Q1 and Q3 values in that order.

Q1 = 24

Q3 = 31

These are the left and right edges of the box.

We can cross choice A off the list because the right edge of the box in that diagram is at 29 instead of 31.

The answer is between C and D.

-------------

The last things to consider are the min and max, which are the smallest and largest elements. These are the left and right tips of the whiskers, assuming that we don't have small or large outliers. In this case, we don't have to worry about outliers.

The min and max is 20 and 34 which must mean the answer is choice C

We can rule out choice D because the max shown here is 35.

-------------

In short, the data set has the following five number summary:

all of these five values correspond to a specific visual feature of the boxplot (see diagram below)

Answer:

You should expect 4 of the next 20 children to enroll to be toddlers.

Step-by-step explanation:

This question is solved by proportions.

So far:

We have that of 2 + 8 = 10 children, 2 are toddlers, so the proportion of toddlers is 2/10 = 0.2.

How many of the next 20 children to enroll should you expect to be toddlers?

0.2 out of 20, so: 0.2*20 = 4

You should expect 4 of the next 20 children to enroll to be toddlers.

Answer:

Where is the full questions?

D none of the above

as it should be ([tex]\sqrt[5]{x}[/tex])^4

Answer:

The p-value of the test is 0.0613 > 0.05, which means that there has not been a statistically significant increase in the number of attempts.

Step-by-step explanation:

Typically there are about 52 such attempts noted each day. Test if there has been a statistically significant increase.

At the null hypothesis, we test if the mean is the same, that is of 52. Thus:

[tex]H_0: \mu = 52[/tex]

At the alternative hypothesis, we test if there has been an increase, that is, if the mean is greater than 52. So

[tex]H_1: \mu > 52[/tex]

Use the standard level for alpha.

So [tex]\alpha = 0.05[/tex]

The test statistic is:

We have the standard deviation for the sample, so t-distribution.

[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, s is the standard deviation of the sample and n is the size of the sample.

52 is tested at the null hypothesis:

This means that [tex]\mu = 52[/tex]

Over the previous 30 days in which there were an average of 57 attempts each day with a standard deviation of 17.2.

This means that [tex]n = 30, X = 57, s = 17.2[/tex]

Value of the test statistic:

[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]

[tex]t = \frac{57 - 52}{\frac{17.2}{\sqrt{30}}}[/tex]

[tex]t = 1.59[/tex]

P-value of the test and decision:

The p-value of the test is the probability of finding a sample mean above 57, which is a right-tailed test with t = 1.59 and 30 - 1 = 29 degrees of freedom.

Using a t-distribution calculator, this p-value is of 0.0613.

The p-value of the test is 0.0613 > 0.05, which means that there has not been a statistically significant increase in the number of attempts.

9514 1404 393

Answer:

Step-by-step explanation:

In general, you solve equations like these by getting the function of the variable by itself on one side of the equal sign. Then you use the inverse function to find the argument of the function. As in problem 3, you may have to go another step or two to get from the value of the function argument to the value of the variable.

1. We need to find sin(θ), then use the arcsine function.

  sin(θ) -0.832 = 0 . . . . given

  sin(θ) = 0.832 . . . . . . add 0.832 to both sides

  θ = arcsin(0.832) ≈ 56.305° . . . . . . use the inverse sine function to find θ

  θ ≈ 56°

__

2. 1/2cos(θ) = 0.214 . . . . given

  cos(θ) = 0.428 . . . . . . multiply by 2

  θ = arccos(0.428) ≈ 64.659° . . . . use the inverse cosine function

  θ ≈ 65°

__

3. 3tan(θ -20°) = 1.43 . . . . given

  tan(θ -20°) = 0.47666... . . . divide by 3

  θ -20° = arctan(0.47666...) . . . . use the arctan function to find θ-20°

  θ -20° ≈ 25.486°

  θ = 45.486° . . . . . . . add 20°

  θ ≈ 45°

_____

Additional comments

Scientific and graphing calculators often require use of a 2nd or SHIFT key to access the inverse trig functions. The inverse function often uses the same key on the calculator. These are generally marked with a -1 superscript: a key might be marked with sin, for example, with sin⁻¹ as its alternate function.

The trig functions of a calculator will usually deal with angles in any of several units. The most common of these are degrees, grads, and radians. Usually, you are required to set the calculator mode to make use of one or the other of these angle measures. For this problem, you need to be sure the calculator is set to degrees mode.

Answer:

y

=

x

2

+

4

x

−

5

Step-by-step explanation:

Answer:

343 square root 1000

Step-by-step explanation:

See Image below:)

Answer:

6 newer games and 10 older games

Step-by-step explanation:

To find how many newer games John can purchase, we divide $30 by $5. If we do the simple math in our head, we will get the answer of 6. Therefore, the amount of newer games John can purchase is 6. Now to find the amount of older games John can buy, we apply the same strategy. We take $30 and we divide it by $3. This will get us the answer of 10. Therefore, the amount of older games John can purchase is 10.

Hope this helps and if it does, don't be afraid to rate my answer as well as maybe give it a "Thanks"? (Or even better a "Brainliest"). And if it’s not correct, I am sorry for wasting your time and good luck finding the correct answer :)

Equation:

[tex]tan(x) = \frac{opp}{adj}[/tex]

x = 44°

Step-by-step explanation:

Since AB is a diameter,

arcAC + arcCB = 180

92° + arcCB = 180

or

arcCB = 88°

ArcCB is the intercepted arc and by definition, the inscribed angle x is half the measure of the intercepted arc. Therefore,

x = (1/2)arcCB

= 44°

Answer:

144 cm³ or 144 cubic centimeters

Step-by-step explanation:

Volume = Area triangle * height

Area triangle = 1/2 ( 3 x 8) = 1/2( 24) = 12

12 x 12 = 144 cm³

If my answer is incorrect, pls correct me!

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-Chetan K