In the coin value formula, V(t)= P(1+r)^t, which parts form the base of the exponential function? Which parts from the constant, or initial value? Which parts form the exponent?

Answer:

(B) sample size is 666

Step-by-step explanation:

given data

CI = 99%

error = 0.05

to find out

sample size

solution

we know that for CI = 99% and E = 0.05 the value of z = 2.58 from table

and no estimate of proportion is given so it is rule take q = p = 0.5

so now we can calculate sample size i.e.

n = (z/E)² ×p ×q

put the value q and p = 0.5 and z and E so we get sample size

n = (z/E)² ×p ×q

n = (2.58/0.05)² ×0.5 ×0.5

n = 665.64

so sample size is 666

so option (B) is right

Answer:

5

Step-by-step explanation:

The amplitude is the distance from the highest to lowest points divided that by 2.

Or the simpliest way when given the function

f(x) = A sin(x)

Where A is the amplitude

To determine the amplitude of the function \( f(x) = 5 \sin x \), let's review the concept of amplitude in the context of sinusoidal functions like sine and cosine.
The general form of a sine function is:
\[ f(x) = A \sin(Bx + C) + D \]
- \( A \) is the amplitude of the function, which determines the height of the wave's peak or the depth of its trough, relative to the center line of the wave.
- \( B \) affects the period of the function, which is the distance over which the wave pattern repeats.
- \( C \) is the phase shift, which determines where the function starts on the x-axis.
- \( D \) is the vertical shift, which moves the wave up or down on the y-axis.
The amplitude \( A \) is always a non-negative number. It represents the maximum value that the function reaches from its middle position (equilibrium). In other words, it's the distance from the middle of the wave to its peak or trough.
In the function you've provided, \( f(x) = 5 \sin x \), there's no phase shift (\( C \)) or vertical shift (\( D \)), and since there's no coefficient multiplying \( x \) inside the sine function, the period is not affected (\( B = 1 \)). The coefficient of \( \sin x \), here \( 5 \), is the amplitude of the function.
So, the amplitude of the function \( f(x) = 5 \sin x \) is simply the coefficient in front of the sine term, which in this case is \( 5 \). Therefore, the amplitude of \( f(x) \) is \( 5 \).

Answer:

First we need to calculate the height of the triangle ( because from that, we can also calculate both x and y)

We know that: h² = b'c'

And in our case:

b' = 9

c' = 3

=> h² = b'c' = 9 · 3

=> h = √(9 · 3) = √27

Now using pythagorean theorem:

(√27)² + 3² = x²

=> x²           = 27 + 9

=> x             = √(27 + 9) = √36 = 6

So x = 6 and the answer is C.

In a triangle, you can define proportions by setting the length ratios and width ratios equal to each other. For example, if you have a triangle with side lengths of 10, 8, and 6 inches, you can set up the proportion 10/8 = 8/6.

In a triangle, there are two common types of proportions: the length ratios and the width ratios.

To define these proportions, you can set the two length ratios equal to each other and the two width ratios equal to each other.

For example, let's say you have a triangle with side lengths of 10 inches, 8 inches, and 6 inches. You can set up the proportion:

10/8 = 8/6

Similarly, for the width ratios, you can set up the proportion:

w/30 = 0.5/5

A) 177.568 thousand.

B) 125.836 thousand.

In this question, it is asking you to use the equation to find the population of ladybugs in a certain year.

Equation we're going to use:

[tex]y = -1.437 x + 197.686[/tex]

We know that the "x" variable represents the number of years since 2010, so that means our starting year is 2010.

Lets solve the question.

Question A:

We need to find the ladybug population is 2024.

2024 is 14 years after 2010, so our "x" variable will be replaced with 14.

Your equation should look like this:

[tex]y = -1.437 (14) + 197.686[/tex]

Now, we solve.

[tex]y = -1.437 (14) + 197.686\\\\\text{Multiply -1.437 and 14}\\\\y=-20.118+197.686\\\\\text{Add}\\\\y=177.568[/tex]

You should get 177.568

This means that the population of ladybugs in 2024 is 177.568 thousand.

Question B:

We need to find the ladybug population is 2060.

2060 is 50 years after 2010, so the "x" variable would be replaced with 50.

Your equation should look like this:

[tex]y = -1.437 (50) + 197.686[/tex]

Now, we solve.

[tex]y = -1.437 (50) + 197.686\\\\\text{Multiply -1.437 and 50}\\\\y=-71.85+197.686\\\\\text{Add}\\\\y=125.836[/tex]

This means that the population of ladybugs in 2060 would be 125.836 thousand.

Answer:

5 or B

Step-by-step explanation:

Explanation:

An absolute value function in the form ...

  f(x) = a|x -h| +k

will have its vertex at (x, y) = (h, k). The sign on scale factor "a" will tell you whether it opens upward (a > 0) or downward (a < 0).

If a is positive, the vertex is a minimum, and the range is [k, ∞).

If a is negative, the vertex is a maximum, and the range is (-∞, k].

The range of an absolute value function is determined by its vertex and the value of 'a'. If 'a' is positive, the function opens upwards and the minimum of the range is the y-coordinate of the vertex. If 'a' is negative, the function opens downwards, the maximum of the range is the y-value of the vertex.

The range of an absolute value function can be determined using the vertex and the value of 'a' in the function’s equation. In an absolute value function, the vertex is the lowest or highest point on the graph, depending on whether the function opens upwards or downwards. The value 'a' influences the direction of the opening: if 'a' > 0, the graph opens upwards, and if 'a' < 0, it opens downwards.

For example, consider the function |a(x-h)|+k, where (h,k) is the vertex. If 'a' is positive, then the minimum range of the function will be 'k', and the function will extend to positive infinity, making the range [k, ∞). If 'a' is negative, the function will extend towards negative infinity, making its maximum value 'k', and thereby setting the range to (-∞, k].

This means, for instance, if we have a function like y = 3|x - 2| + 1, the value of 'a' is 3, which is positive, thus the function opens upwards, and the vertex is (2,1), which indicates that the range of this function is [1,∞).

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Answer:

-sqrt(5) ≤ x ≤ sqrt(5)

Step-by-step explanation:

x^2-5≤0

Add 5 to each side

x^2-5+5≤0+5

x^2 ≤5

Take the square root of each side, remembering to flip the inequality for the negative sign.  Since this is less than we use and in between

sqrt(x^2) ≤ sqrt(5)   and sqrt(x^2) ≥ -sqrt(5)  

x ≤ sqrt(5) and x ≥- sqrt(5)  

-sqrt(5) ≤ x ≤ sqrt(5)

Answer: 70% chance of winning

Step-by-step explanation: What is your question? Are you trying to ask the probability of winning? (I will assume this and answer)

The whole case of selecting to numbers : 5C2 = 5 X 4 / 2 = 10

the cases of getting a odd sum : select 1 odd number and 1 even number

=> select 1 odd number : 7 or 9 => 2 cases

=> select 1 even number: 4,6,8 => 3 cases

you multiply 2 and 3 and divide it by 2 because order doesn't matter

so the answer is 1 - (3/10) = 0.7  

The player in the game has an equal chance of winning or losing.

In this problem, we are given a box containing five slips of paper, each with a number written on it. The first player draws two slips and adds the two numbers together. To determine if the player wins or loses, we need to determine if the sum of the two numbers is even or odd.

To solve this problem, we can list all the possible pairs of numbers and find out if the sum of each pair is even or odd. If the sum is even, the player wins; if the sum is odd, the player loses. We can do this by considering the possible outcomes:

From the listed outcomes, we can see that there are 5 even sums and 5 odd sums.

Therefore, the player has an equal chance of winning or losing in this game.

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Answer:

Step-by-step explanation:

After the 440 pennies are added, the bank is 3/5 full.  It started out 1/10 full, so

3/5 - 1/10 is the amount of space in the bank that the 440 pennies took up, or

1/2.  Use proportions to solve this, with number of pennies on the top and the fraction of the bank that is filled on the bottom:

[tex]\frac{440}{\frac{1}{2} }=\frac{x}{1}[/tex]

where x is the number of pennies (our unknown) that it will take to fill the bank (1).  Cross multiply to get

[tex]\frac{1}{2}x=440[/tex]

so x = 880

Answer:

C!!!!!! :She made a mistake when finding the additive inverse of (7n2 – 5n + 6).

Step-by-step explanation:

i just did the assignment on edge

She made a mistake when finding the additive inverse of (7n2 – 5n + 6).

Additive inverse absolutely means converting the signal of the wide variety and adding it to the original range to get a solution identical to zero. The properties of additive inverse are given underneath, based totally on the negation of the original wide variety. as an instance, if x is the authentic quantity, then its additive inverse is -x.

Additive inverse is what you upload to a number to make the sum zero. for instance, the additive inverse of 4 is -four due to the fact their sum is 0. while numbers are delivered together to get 0, then we are saying both the numbers are additive inverses of every different.

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Answer:

  A.  Y = -6X + 9

Step-by-step explanation:

Solving for y, we can find the slope of the given line. It is the coefficient of x, 1/6.

  -12y = -2x -1

  y = 1/6x +1/12

The perpendicular line will have a slope that is the negative reciprocal of this:

  m = -1/(1/6) = -6

The y-intercept will be the y-value corresponding to x=0. That value is b=9, given to us by the point the line is to go through. So, we have the slope-intercept form ...

  y = mx + b

  y = -6x + 9

Answer:

y=4x-4

Step-by-step explanation:

The equation of a line is slope-intercept form is: y=mx+b where m is the slope and b is the y-intercept. This is the required form I think. Your document says write in slope... can't read the rest because it is cut off.

I'm actually going to use point-slope form which is: y-y1=m(x-x1) where m is the slope and (x1,y1) is a point we know that is on the line.

We have m=4.

We can actually find a point on the line. Both the line and the curve y=x^2 cross at x=2.

So we find the corresponding y-coordinate on our line to x=2 by plugging into x^2.

x^2 evaluated at x=2 gives us 2^2=4.

So we have the slope m=4 and a point (x1,y1)=(2,4) on the line.

Let's plug it into the point-slope form:

y-4=4(x-2)

Now the goal was y=mx+b form so let's solve our for y.

y-4=4(x-2)

Distribute 4 to terms in ( ):

y-4=4x-8

Add 4 on both sidea:

y=4x-4

Answer:

Radians help make calculations easier. Also, They measure arc-length on the circle, giving you angle in the sense which you can actually represent on the number line without any conversion.

Answer:

[tex]2.6\times 10^{19}m^{3}[/tex]

Step-by-step explanation:

we have given thickness of atmosphere =50 km

radius of earth =6400 km

average temperature of atmosphere=15°C

Average pressure of atmosphere= 0.20 atm

we have to calculate the volume of atmosphere

so the we have to calculate the volume of atmosphere = ( volume of earth +atmosphere) - volume of earth

volume of atmosphere =[tex]\frac{4}{3}\times\pi \times \left ( 6400+50 \right )^{3}-\frac{4}{3}\times \pi\times 6400^3[/tex]

=[tex]2.6\times 10^{19}m^{3}[/tex]

To calculate the total volume of the Earth's atmosphere, one has to use the principles of geometry for spheres and subtract the volume of the Earth from the volume of the Earth and its atmosphere.

The volume of the Earth's atmosphere can be calculated by using the geometry of spheres and the characteristics provided: the average thickness of the Earth's atmosphere (50 km) and Earth's radius (6,400 km). We model Earth and its atmosphere as a larger sphere encapsulating a smaller one and define the larger sphere's radius as the Earth's radius plus the thickness of the atmosphere.

To get the most accurate results, use the accurate value of π and proper bracket organization for your calculations.

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Answer:

$165,000

Step-by-step explanation:

$50,000 + $100,000 + $15,000 = $165,000

Hope this helps C:

Everett McCook's annual payment for liability insurance can be calculated by dividing his total liability coverage by the annual distance he drives to college.

To determine Everett McCook's annual payment for liability insurance, we need to calculate the total premium he pays. Since he drives 5 miles each way to the college, his daily distance is 10 miles. To calculate his annual distance, we multiply this by the number of days he drives to college in a year. Assuming he works on all weekdays, he drives 5 days a week for 52 weeks, resulting in 260 days a year. Therefore, his annual distance is 260 * 10 = 2600 miles.

Now, let's calculate his annual payment. Since his liability insurance includes $50,000 for single bodily injury, $100,000 for total bodily injury, and $15,000 for property damage, we can add these amounts together. Therefore, his liability coverage is $50,000 + $100,000 + $15,000 = $165,000.

Lastly, we divide the total liability coverage by the annual distance to find the cost per mile. So, the annual payment is $165,000 / 2600 = $63.46 per mile.

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Answer:

  a) 0.2562

  b) no

Step-by-step explanation:

a) A binomial probability calculator or app can tell you that for bin(941, 0.75) the probability P(X ≥ 715) ≈ 0.2562

__

b) "significantly high" usually means the probability is less than 5%, often less than 1%. An event that occurs when its probability is almost 26% is not that unusual.

Answer:

i think its C

Step-by-step explanation:

the frequency is in median form and the speed is in mean form

Answer:

Step-by-step explanation:

There are 40 numbers in your data set. (This is the sum of the numbers in the Frequency column.) This is an even number, so the median is the average of the middle two Speed values when they are sorted from lowest to highest. The frequency chart already tells you the result of that sorting. From the chart, we can see that there are 9 Speed values below 15, and 12 values that are 15. That tells us that Speed values number 20 and 21 on the list both have a value of 15, so that is the value of the median.

__

The mode is the value that occurs most frequently. Obviously that value is 15, since it occurs 12 times and no other number occurs more than 6 times.

__

Finding the mean is a little more work. For that, we have to add up the 40 numbers and divide by 40. The fact that some numbers are repeated can help shorten that effort.

  sum of all values = 12×1 + 13×2 + 14×6 + 15×12 + 16×6 + 17×5 + 18×1 + 19×2 + 20×4 + 21×1 = 640

  mean = (sum of all values)/(number of values) = 640/40

  mean = 16

Let Home runs = X

Triples would be X-3 ( 3 less triples than home runs)

Doubles would be 3x ( 3 times as many doubles as home runs)

Singles would be 45(x-3) ( 45 times as many singles as triples)

Simplify the equation for singles to be 45x-153

Now you have X + x-3 + 3x + 4x-135 = 262

Simplify:

50x - 138 = 262

Add 138 to both sides:

50x = 400

Divide both sides by 50:

x = 400/50

x = 8

Home runs = x = 8

Triples = x-3 = 8-3 = 5

Doubles = 3x = 3(8) = 24

Singles = 45(x-3) = 45(8-3) = 45(5) = 225

By setting up a system of equations using the given relationships between the types of hits, we can calculate that Ichiro Suzuki hit 225 singles, 24 doubles, 5 triples, and 8 home runs in the 2004 season.

To solve this problem, we will set up a system of equations based on the information given:

The total number of hits is the sum of singles, doubles, triples, and home runs, which gives us the equation:

S + D + T + H = 262

Substitute the expressions for T, D, and S in terms of H into this equation:

45(H - 3) + 3H + (H - 3) + H = 262

This simplifies to:

45H - 135 + 3H + H - 3 + H = 262

Combining like terms yields:

50H - 138 = 262

Add 138 to both sides to get:

50H = 400

Divide by 50 to find H:

H= 8

Using H, we can find T, D, and S:

Therefore, Ichiro Suzuki hit 225 singles, 24 doubles, 5 triples, and 8 home runs in the 2004 season.

Answer:

Step-by-step explanation:

The given parallelogram is attached.

First, we have to define some terms:

So, if we observe points D, G and J, from given options, they are non-collinear and non-coplanar, because they are not on the same line, nor plane.

Answer:

1st question: M=22.62 while C=75.38

2nd question: M=.22 while C=1.97

Step-by-step explanation:

If a mirror costing x dollars is marked up 30%, then we have to find x such that 30%x+x is 98 dollars.

We are solving:

.3x+x=98

Combine like terms:

1.3x=98

Divide both sides by 1.3:

x=75.38

M=98-75.38=22.62

C=75.38

So M=22.62 while C=75.38.

If ream of paper cost x and is marked up 11%, then we have to find x such that 11%x+x is 2.19.

We are solving:

.11x+x=2.19

1.11x=2.19

x=1 97

M=2.19-1.97=.22

So M=.22 while C=1.97

Answer:

A mirror selling for $98, marked up 30%;

M = $22.62

C = $75.38

A ream of paper selling for $2.19, marked up 11%;

M = $0.22

C = $1.97

Step-by-step explanation:

Hope it helps.

NOTE: (gºf)(6) means g(f(6)).

First find f(6).

f(6) = 2(6) - 6

f(6) = 12 - 6 or 6.

We now find g(6).

g(6) = (6)^3

g(6) = 216

ANSWER:

(gºf)(6) = 216

Answer:

Descartes' rule states that the possible number of the positive roots of a polynomial is equal to the number of sign changes in the coefficients of the terms or less than the sign changes by a multiple of 2.

The Fundamental Theorem of Algebra states that every polynomial equation over the field of complex numbers of degree higher than 1 has a complex solution, furthermore any polynomial of degree n has n roots.  

Remember that the complex numbers include the real numbers.

Suppose we are given the polynomial x^3+3x^2-x-x^4-2, we arrange the terms of the polynomial in the descending order of exponents:

-x^4+x^3+3x^2-x-2, count the number of sign changes, there are 2 sign changes in the polynomial, so the possible number of positive roots of the polynomial is 2 or 0.

returning to our polynomial above, -x^4+x^3+3x^2-x-2, it has degree 4 and so has n roots. Note that complex roots always come in pairs, so here is what can be said from these two rules:  

degree 1 has 1 real root

degree 2 has 2 real roots or 2 complex roots

degree 3 has 3 real roots or 1 real root and 2 complex roots

degree 4 has 4 real roots or 2 real roots and 2 complex roots  

note that if the degree is odd, there will be at least 1 real root

Step-by-step explanation:

The number of complex roots and the possible positive and negative real roots of a polynomial can be predicted using the Fundamental Theorem of Algebra and Descartes' Rule of Signs. The Fundamental Theorem of Algebra ensures at least one complex root for every polynomial, while Descartes' Rule predicts possible real roots based on the number of sign changes in the polynomial equation.

To predict the number of complex roots and find the number of possible positive and negative real roots to a polynomial, you can use both Descartes' Rule and the Fundamental Theorem of Algebra. These two concepts in mathematics can give us interesting insights into the roots of polynomial equations.

First, the Fundamental Theorem of Algebra states that every non-constant polynomial equation has at least one complex root. This theorem can ensure us that we have a starting point, knowing that every polynomial equation will have at least one solution, even if it's complex.

Second, you can use Descartes' Rule of Signs to predict possible positive and negative roots. This rule uses the number of sign changes in the polynomial to give possible number of positive real roots. You can get the possible number of negative real roots by replacing x with -x and count the sign changes again.

For example, for the equation f(x) = x5 – 4x4 + 2x3 + 8x2 -12x + 6, there are two sign changes in the original equation, so there can be two or zero positive real roots. If we replace x with -x, we get three sign changes, suggesting three or one negative real roots.

An important aspect to remember is that Descartes' Rule of Signs gives us possible quantities of roots, but not the exact amount or their values, and it can't predict complex roots. However, by utilizing the Fundamental Theorem of Algebra in conjunction with Descartes' Rule, we can get a fuller picture of the roots of a polynomial equation.

Answer:

D

Step-by-step explanation:

The midpoint formula is

[tex]M=(\frac{x_{1}+x_{2}  }{2},\frac{y_{1}+y_{2}  }{2})[/tex]

Filling in our coordinates where they go gives us:

[tex]M=(\frac{1+4}{2},\frac{1-16}{2})[/tex] so

[tex]M=(\frac{5}{2},\frac{-15}{2})[/tex]

Answer:

Option 1:(x-4)^2+y^2=100

Step-by-step explanation:

Given center = (h,k) = (4,0)

The point (-2,8) lies on circle which means the distance between the point and center will be equal to the radius.

So,

The distance formula will be used:

[tex]d = \sqrt{(x_2-x_1)^{2}+(y_2-y_1)^{2}} \\=\sqrt{(4+2)^{2}+(0-8)^{2}}\\=\sqrt{(6)^{2}+(-8)^{2}}\\=\sqrt{36+64}\\ =\sqrt{100}\\ =10\ units[/tex]

Hence radius is 10.

The standard form of equation of circle is:

(x-h)^2+(y-k)^2 = r^2

Putting the values

(x-4)^2+(y-0)^2=10^2

(x-4)^2+y^2=100

Hence option 1 is correct ..

Answer:

A

Step-by-step explanation:

Answer:

216.4 mm^2

Step-by-step explanation:

The polygon has 9 sides.

Divide the polygon into 9 congruent triangles. Each triangle has 2 sides of length 8.65 mm, so each triangle is isosceles. The measure of each internal angle of the polygon is (9 - 2)(180)/9 = 140 degrees. The base angles of an isosceles triangle measures 70 deg. The vertex angle measures 40 deg. Draw a segment from the center of the polygon to the midpoint of a side. This segment is the altitude of the triangle. Now the triangle has been split into two right triangles. The angles of the right triangle are 70, 90, and 20. 3.65 mm is the length of the hypotenuse. The length of the altitude is found with trig.

sin A = opp/hyp

sin 70 = h/8.65

h = 8.65 sin 70

h = 8.1283 mm

Now with the altitude, we can find the length of half of a side of the polygon.

a^2 + b^2 = c^2

x^2 + h^2 = 8.65^2

x^2 + 8.1283^2 = 8.65^2

x = 2.9585

Half a side measures 2.9585 mm.

The side of the polygon measures 5.9169 mm.

The area of the polygon is 9 times the area of one triangle.

area = 9 * base * height/2

area = 9 * 5.9169 mm * 8.1283 mm / 2

area of polygon = 216.4 mm^2

Answer:

  1

Step-by-step explanation:

There are about 110,000 days in 300 years, so the expected number of failures is about 10/11 ≈ 1.

_____

This assumes the launch conditions are identical for each of the launches, or that whatever variation there might be has no effect on the probability. These are bad assumptions.

A failure rate of 1 in 100,000 with daily launches over 300 years would statistically result in approximately 1 failure.

If the chance of a space shuttle failure is 1 in 100,000, we can calculate the expected number of failures over 300 years with the assumption that a shuttle is launched every day. There are 365 days in a year, so over 300 years, there would be 300 × 365 = 109,500 launches. Given the failure rate of 1 in 100,000, we would then expect approximately 109,500 / 100,000 = 1.095 failures, which rounded to the nearest integer is 1 failure.

In other words, if the failure rate estimated by the shuttle program management were accurate and a shuttle was launched every day for 300 years, one would expect about 1 failure during that time span.

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Answer:

95% confidence interval for the population mean is 20.255 and 17.945

Step-by-step explanation:

given data

mean = 19.1

standard deviation = 1.5

n = 9

to find out

95% confidence interval for the population mean

solution

we know 95% confidence interval formula i.e.

mean +/- t * standard deviation/[tex]\sqrt{n}[/tex]   .............1

here t for 9 students 2.31 ( from t table)

so put all value n t standard deviation and mean in equation 1

= mean +/- t * standard deviation/[tex]\sqrt{n}[/tex]

= 19.1 +/- 2.31 * 1.5/[tex]\sqrt{9}[/tex]

= 19.1 +/- 2.31 * 1.5/[tex]\sqrt{9}[/tex]  

= 20.255 and 17.945

95% confidence interval for the population mean is 20.255 and 17.945

The 95% confidence interval for the population mean of student ages, based on a sample mean of 19.1, standard deviation of 1.5, and a sample size of 9, is approximately (17.95, 20.25).

To construct a 95% confidence interval for the sample mean, first you need to know the sample mean, the sample standard deviation, and the sample size. In this case, the pertinent information is as follows: the sample mean (X) is 19.1 years, the sample standard deviation (s) = 1.5 years, and the sample size (n) = 9. The formula used for a 95% confidence interval is X ± t*(s/√n). In this case, the value for 't' with 8 degrees of freedom (n-1) is approximately 2.306 from the t-distribution table.

To calculate the 95% confidence interval, we then substitute the known values into the formula: 19.1 ± 2.306*(1.5/√9), yielding an interval of 19.1 ± 1.15, so the 95% confidence interval for the population mean is approximately (17.95, 20.25). This means that we estimate with 95% confidence that the true average age of all students in the class is between 17.95 and 20.25 years.

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-- average price of gas ... continuous.  An average can come out to be any number, with a huge string of decimal places.  There are no numbers it CAN'T be.

-- car's speed ... continuous.  Between zero and the car's maximum top speed, there are no numbers it CAN'T be.

-- number of cars ... discrete.  It has to be a whole number.  There can't be a half a car or 0.746 of a car passing through.  

-- number of phone calls ... discrete.  It has to be a whole number.  There can't be a half of a call or 0.318 of a call made.

-- salaries ... I'm a little fuzzy on this one.  The employer can set a person's salary to be anything he wants it to be.  If they want it to be a whole number, or ANY fraction, they can do it ... there's no number it CAN'T be.  BUT ... when it comes time to actually pay him, THAT has to be a whole number of pennies.  There are actually a lot of numbers that they CAN'T pay, because they can't give him half of a penny, or 0.617 of a penny.

So I'm going to say that salary is a discrete variable.  

A because it has a set between the whole numbers 1 and 4 (and slightly beyond those in decimals)

Answer:

y

Step-by-step explanation:

Flip b/x to the proportion x is now y.

Answer:

b/x = (x + y)/b

where c = x + y then

b/x = c/b

Step-by-step explanation:

Considering the larger of the three triangles the image represents,

b and a in light of the angle A form by both sides (the angle opposite the side a) would have a relationship

Cos A = x/b

hence b/x = 1/Cos A

Considering the largest triangle,

Cos A = b/(x +y)

hence,

(x + y)/b = 1/Cos A

as such,

b/x = (x + y)/b