twice the square of the number

At three meters, the difference in the decibel level if and if not connected to the speaker is 1.5 dB

The reason for arriving at the above value is as follows:

The known parameters:

The audio sensed by the microphone when connected to the speaker are;

0 meters = 60 decibels

The level of the decibel decrease by half for each additional meter;

Therefore, when the microphone is connected to the speaker, we have;

[tex]\begin{array}{|c|cc|}\mathbf{Distance \ (m)}&&\mathbf{Sound \ (dB)}\\0&&60\\1&&30\\2&&15\\3&&7.5\end{array}\right][/tex]

If the microphone is not connected to the speaker, we have;

0 meters = 30 decibels

The level of the decibel decreasing by 8 dB for every additional meter from the speaker, therefore, when the microphone is not connected to the speaker we have;

[tex]\begin{array}{|c|cc|}\mathbf{Distance \ (m)}&&\mathbf{Sound \ (dB)}\\0&&30\\1&&22\\2&&14\\3&&6\end{array}\right][/tex]

At three meters from the speaker, the difference in the decibel level when it is connected and when it is not connected to the speaker is therefore;

Decibel level at 3 meters when connected, s₁ = 7.5 dB

Decibel level at 3 meters when not connected, s₂ = 6 dB

The difference in the decibel level = s₂ - s₁ = 7.5 dB - 6 dB = 1.5 dB

The difference in the decibel level when connected to the speaker and when not connected to the speaker is 1.5 dB

Learn more about sound level here:

https://brainly.com/question/11047787

Answer:

= - 54

Step-by-step explanation:

- 99 + 3^2•5

- 99 + 9 × 5

- 99 + 45

= - 54

Answer: There is an moderate relationship between  the aptitude test scores with the chronological ages of the subjects.

Step-by-step explanation:

Here , variables →  aptitude test scores and chronological ages of the subjects.

Since correlation coefficient (-0.42) lies between  -0.5 and -0.3 .

[-0.5< -0.42< -0.3]

That means there is an moderate relationship between  the aptitude test scores with the chronological ages of the subjects.

Answer:

Step-by-step explanation:

You need to re copy and paste it, I can’t see the full possible answers/question.

Answer:18

Step-by-step explanation:

because 36 is divided by 2 equals 18cm

Answer:

6cm x 6cm

Step-by-step explanation:

It's a square so the dimensions have to be the same (6x6 = 36). Even though 18 is a factor of 36, 18cm by 2cm would make a rectangle.

Answer:

675 km/hr and 75 km/hr

Step-by-step explanation:

Let the speed of plane in still air be x and the speed of wind be y.

ATQ, (x+y)*(40/60)=500 and (x-y)*(50/60)=500. Solving it, we get x=675 and y=75

Answer:

the answer is c

Step-by-step explanation:

Answer:

See the explanation and attached images for the answers.

Step-by-step explanation:

a) 1-step transition matrix:

See the attached image for transition matrix.

Let the matrix be M

if the stock closes higher on a day, the probability that it closes higher the next day is 0.65.

If the stock closes lower on a day, the probability that it closes higher the next day is 0.45

if the stock closes higher on a day, the probability that it closes lower the next day is 1 - 0.65 = 0.35

if the stock closes lower on a day, the probability that it closes lower the next day is 1 - 0.45 =0.55

b)

To compute probability for 3 days later multiply matrix M (from part a) thrice i.e. M*M *M

[tex]M^{3} = \left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right]*\left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right]*\left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc}0.65 * 0.65 + 0.35 * 0.45 &0.65 * 0.35 + 0.35 * 0.55 \\0.45 * 0.65 + 0.55 * 0.45 &0.45 * 0.35 + 0.55 * 0.55 \end{array}\right] * \left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc}0.58&0.42\\0.54&0.46\end{array}\right]*\left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc} 0.58 * 0.65 + 0.42 x 0.45&0.58 * 0.35 + 0.42 * 0.55 \\0.54 * 0.65 + 0.46 * 0.45 &0.54 * 0.35 + 0.46 * 0.55 \end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc}0.566&0.434\\0.558&0.442\end{array}\right][/tex]

The probability that it will close higher on Thursday is 0.566. See the transmission matrix of M³ for higher-higher. This can be interpreted as:

if the stock closed higher on Monday, the probability that it closes higher the on Thursday (three days later) is 0.566

[tex]\\ \sf\longmapsto \dfrac{AK}{DK}=\dfrac{CK}{BK}[/tex]

[tex]\\ \sf\longmapsto \dfrac{14}{12}=\dfrac{4x+1}{3x+3}[/tex]

[tex]\\ \sf\longmapsto \dfrac{7}{6}=\dfrac{4x+1}{3x+3}[/tex]

[tex]\\ \sf\longmapsto 7(3x+3)=6(4x+1)[/tex]

[tex]\\ \sf\longmapsto 21x+21=24x+6[/tex]

[tex]\\ \sf\longmapsto 24x-21x=21-6[/tex]

[tex]\\ \sf\longmapsto 3x=15[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{15}{3}[/tex]

[tex]\\ \sf\longmapsto x=5[/tex]

Answer:

650 calls

Step-by-step explanation:

so since you have 18$ per month plus 5 cents per call you would do

18+0.5n(n represent the number of calls)= the total fee of $50.50 cents.

thus,now you need to figure out how much the phone calls were without the monthly fee so you would do:

50.50-18=32.50

so 32.50 is the price of all the phone calls

then you divide 32.50 by 0.05 which equals to 650

meaning that n=650

hope I helped!

Answer:

i don't understand the question

This value is approximate.

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

Explanation:

To find the perimeter, we simply add up the lengths of the three external sides.

The horizontal side from D to E is 16 units long since |-10-6| = 16. I subtracted the x coordinates of the points and applied absolute value. You could also count out the spaces and you should count 16 spaces from D to E.

Unfortunately, the diagonal lengths aren't as straight forward. We have two options here: The pythagorean theorem, or the distance formula.

I'll go with the distance formula.

Let's find the distance from C to D, aka the length of side CD

[tex]C = (x1,y1) = (-1,-2)\\\\D = (x2,y2) = (-10,0)\\\\d = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}\\\\d = \sqrt{(-1-(-10))^2 + (-2-0)^2}\\\\d = \sqrt{(-1+10)^2 + (-2-0)^2}\\\\d = \sqrt{(9)^2 + (-2)^2}\\\\d = \sqrt{81 + 4}\\\\d = \sqrt{85}\\\\d \approx 9.2195\\\\[/tex]

Side CD is roughly 9.2195 units long.

Repeat this idea to find the length of CE

[tex]C = (x1,y1) = (-1,-2)\\\\E = (x2,y2) = (6,0)\\\\d = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}\\\\d = \sqrt{(-1-6)^2 + (-2-0)^2}\\\\d = \sqrt{(-7)^2 + (-2)^2}\\\\d = \sqrt{49 + 4}\\\\d = \sqrt{53}\\\\d \approx 7.2801\\\\[/tex]

Side CE is roughly 7.2801 units long

The perimeter of triangle CDE is approximately...

P = DE+CD+CE

P = 16 + 9.2195 + 7.2801

P = 32.4996

This then rounds to 32.5 units. The answer is choice C.

Answer:

32.8 miles

Step-by-step explanation:

Amy is driving to Seattle. Suppose that the remaining distance to drive (in miles) is a linear function of her driving time (in minutes). When graphed, the function gives a line with a slope of -0.95. See the figure below. Amy has 48 miles remaining after 31 minutes of driving. How many miles will be remaining after 47 minutes of driving?

Answer: The general equation of a line is given as y = mx + c, where m is the slope of the line and c is the intercept on the y axis. Given that the slope is -0.95, substituting in the general equation :

y = -0.95x + c

Amy has 48 miles remaining after 31 minutes of driving, to find c, we substitute y = 48 and x = 31. Therefore:

48 = -0.95(31) + c

c = 48 + 0.95(31)

c = 48 + 29.45

c = 77.45

The equation of the line is

y = -0.95x + 77.45

After 47 minutes of driving, the miles remaining can be gotten by substituting x = 47 and finding y.

y = -0.95(47) + 77.45

y = -44.65 + 77.45

y = 32.8 miles

Step-by-step explanation:

Hey, there!!

Look this figure, simply we find that;

In triangle ABC,

angle CBD is an exterior angle of a triangle.

and its measure is 90°

Then,

angle CBD= y +48° {sum of interior opposite angle is equal to exterior angle or from theorem}.

or, 90°= y + 48°

Shifting, 48° in left side,

90°-48°= y

Therefore, the value of y is 42°.

Hope it helps...

Answer:

18

Step-by-step explanation:

Using Zero Product Property, we can split this equation into two separate equations by setting each factor to 0. The equations are:

10x + 33 = 0 or 11x + 60 = 0

10x = -33 or 11x = -60

x = -33/10 or x = -60/11

Multiplying the two solutions together, we get -33/10 * -60/11 = 1980 / 110 = 18.

the answer is 11/7.you can see the image

Answer:

[tex]\boxed {\boxed {\sf \frac{11}{7}}}[/tex]

Step-by-step explanation:

The slope describes the direction and steepness of a line. The formula is:

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

Where (x₁, y₁) and (x₂, y₂) are the points the line contains. For this problem, the line contains the points (2,7) and (-5, -4). Therefore:

Substitute these values into the formula.

[tex]m= \frac{ -4 -7}{-5-2}[/tex]

Solve the numerator (-4 -7 = -11).

[tex]m= \frac{ -11}{-5-2}[/tex]

Solve the denominator (-5-2 = -7).

[tex]m= \frac{ -11}{-7}[/tex]

Simplify the fraction. The 2 negative signs cancel each other out.

[tex]m= \frac{11}{7}[/tex]

The slope of the line is 11/7

Answer:

26ft

Step-by-step explanation:

10^2 +24^2 =AB^2

AB=26

Answer: 26 ft

Step-by-step explanation:

a^2+b^2=c^2

10^2+24^2 = c^2

100+576=c^2

Sqrt 676 = c

C = 26

Step-by-step explanation:

y² - x² + 1 = 50

y² = x² - 1 + 50 = x² + 49

y = ±sqrt(x² + 49)

this is not a function in that sense, as for every x there are not one but 2 y (result) values.

Answer:

3)  20% of the students earned a D

Step-by-step explanation:

9 students got a D.

5 students got a C.

14 students got a B.

17 students got an A.

Total number of students:

9 + 5 + 14 + 17 = 45

1)  1/5 of the students earned a C

1/5 of 45 = 9

5 students got a C

False

2) 3% more students earned an A then B

3 more students got an A than a B, but not 3%.

False

3)  20% of the students earned a D

20% of 45 = 9

9 students got a D.

True

4)  1/4 of the class earned a B​

1/4 of 45 = 11.25

There were 14 B's.

False

Answer: 3)  20% of the students earned a D

Answer:

48

Step-by-step explanation:

Do 60*.80

60 represent the total points the test was worth

.80 represents the % number

The percentage is calculated by dividing the required value by the total value and multiplying by 100.

Required percentage value = a

total value = b

Percentage = a/b x 100

100% = 60

80% = 48

The points Salema earned are 48 points.

The percentage is calculated by dividing the required value by the total value and multiplying by 100.

Example:

Required percentage value = a

total value = b

Percentage = a/b x 100

Example:

50% = 50/100 = 1/2

25% = 25/100 = 1/4

20% = 20/100 = 1/5

10% = 10/100 = 1/10

We have,

Salema's score = 80%

Total score in the test = 60 points

Salema's score.

= 80% of 60 points

= 80/100 x 60

= 48

Thus,

The points Salema earned are 48 points.

Learn more about percentages here:

https://brainly.com/question/11403063

#SPJ2

Answer:

[tex]\mathbf{P(X=5) =0.0888}[/tex]    

P(x ≤ 5 ) = 0.9707

P ( x ≥ 6) = 0.0293

Step-by-step explanation:

The probability of a binomial mass distribution can be expressed with the formula:

[tex]\mathtt{P(X=x) =(^{n}_{x} ) \ \pi^x \ (1-\pi)^{n-x}}[/tex]

[tex]\mathtt{P(X=x) =(\dfrac{n!}{x!(n-x)!} ) \ \pi^x \ (1-\pi)^{n-x}}[/tex]

where;

n = 8 and π = 0.36

For x = 5

The probability [tex]\mathtt{P(X=5) =(\dfrac{8!}{5!(8-5)!} ) \ 0.36^5 \ (1-0.36)^{8-5}}[/tex]

[tex]\mathtt{P(X=5) =(\dfrac{8!}{5!(3)!} ) \ 0.36^5 \ (0.64)^{3}}[/tex]

[tex]\mathtt{P(X=5) =(\dfrac{8 \times 7 \times 6 \times 5!}{5!(3)!} ) \times \ 0.0060466 \ \times 0.262144}[/tex]

[tex]\mathtt{P(X=5) =(\dfrac{8 \times 7 \times 6 }{3 \times 2 \times 1} ) \times \ 0.0060466 \ \times 0.262144}[/tex]

[tex]\mathtt{P(X=5) =({8 \times 7 } ) \times \ 0.0060466 \ \times 0.262144}[/tex]

[tex]\mathtt{P(X=5) =0.0887645}[/tex]

[tex]\mathbf{P(X=5) =0.0888}[/tex]     to 4 decimal places

b. x ≤ 5

The probability of P ( x ≤ 5)[tex]\mathtt{P(x \leq 5) = P(x = 0)+ P(x = 1)+ P(x = 2)+ P(x = 3)+ P(x = 4)+ P(x = 5})[/tex]

[tex]{P(x \leq 5) = ( \dfrac{8!}{0!(8!)} \times (0.36)^0 \times (1-0.36)^8 \ ) + \dfrac{8!}{1!(7!)} \times (0.36)^1 \times (1-0.36)^7 \ +[/tex][tex]\dfrac{8!}{2!(6!)} \times (0.36)^2 \times (1-0.36)^6 \ + \dfrac{8!}{3!(5!)} \times (0.36)^3 \times (1-0.36)^5 + \dfrac{8!}{4!(4!)} \times (0.36)^4 \times (1-0.36)^4 \ + \dfrac{8!}{5!(3!)} \times (0.36)^5 \times (1-0.36)^3 \ )[/tex]

P(x ≤ 5 ) = 0.0281+0.1267+0.2494+0.2805+0.1972+0.0888

P(x ≤ 5 ) = 0.9707

c. x ≥ 6

The probability of P ( x ≥ 6) = 1  - P( x  ≤ 5 )

P ( x ≥ 6) = 1  - 0.9707

P ( x ≥ 6) = 0.0293

Answer: a. paired samples;

Step-by-step explanation:

Paired samples are samples in which each data point in one sample is uniquely paired to a data point in the other sample.

Here, we have a paired sample of fecal boluses for gerbils by characterizing then as "No Drug" and "Drug".

hence, the design of this study is paired samples.

So, option A is correct.

NOTE : Independent samples are opposite of paired samples.

Testing the significance of a correlation require to check relation between two variables.

Answer:

y = |x + 2| + 1

Step-by-step explanation:

Parent Graph: f(x) = a|bx + c| + k

a is vertical stretch/shrink

b is horizontal stretch/shrink

c is horizontal movement left/right

k is vertical movement up/down

Since we are given an equation and we want to move it 1 unit up (vertical movement up), we only manipulate k:

y = |x + 2| + k

k = 1

y = |x + 2| + 1

Answer:

y = |x+2| + 1

Step-by-step explanation:

The equation will be y = |x+2| + 1.

By translating the graph one unit up, the equation will simply change by adding +1 to the graph, outside of the absolute value part.

Answer:  Choice C

This is because the input n = 2 leads to the output n-2 = 2-2 = 0

As another example: the input n = 4 leads to the output n-2 = 4-2 = 2

Whatever the input is, subtract 2 from it to get the output.

Answer:

Hello,

Step-by-step explanation:

This a method knowing nothing.

1+3+5+7+9=25

425-25=400

400/5=80

Numbers are 80+1,80+,80+5,80+7,80+9 whose sum is 425.

[tex]\\ \sf\longmapsto A=πr^2[/tex]

[tex]\\ \sf\longmapsto A=3.14(5)^2[/tex]

[tex]\\ \sf\longmapsto A=3.14(25)[/tex]

[tex]\\ \sf\longmapsto A=78.5cm^2[/tex]

Answer:

work is shown and pictured

Answer:

Hi, there!!!

The answer would be 2(2x-1)/x(x-4).

See explanation in picture.

Hope it helps...

Complete Question

An IQ test is designed so that the mean is 100 and the standard deviation is 24 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with 95% confidence that the simple mean is with in 3 IQ points of the true mean. Assume that standard deviation  = 24 and determine the required sample size using technology. Determine if this is a reasonable sample size for a real world calculation.

The required sample size ______ (round up to the nearest integer.

Answer:

The sample size is  [tex]n = 246[/tex]

Step-by-step explanation:

From the question we are told that

    The  mean is  [tex]\mu = 100[/tex]

     The  standard deviation is  [tex]\sigma = 24[/tex]

     The  margin of error is  [tex]E = 3[/tex]

Given that the confidence level  is  95% then the level of significance is mathematically evaluated as

         [tex]\alpha = 100 - 95[/tex]

         [tex]\alpha = 5\%[/tex]

=>        [tex]\alpha = 0.05[/tex]

Next we obtain the critical value of  [tex]\frac{ \alpha }{2}[/tex] from the normal distribution table the value is

            [tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]

The sample size is evaluated as

          [tex]n = [ \frac{ Z_{\frac{\alpha }{2} } * \sigma }{E }]^2[/tex]

=>       [tex]n = [ \frac{ 1.96 * 24 }{3 }]^2[/tex]        

=>      [tex]n = 246[/tex]

to check if this n is applicable in real world then we calculate E and  compare it with the given E