Section A:trigonometry

Answer:

5.33

Step-by-step explanation:

The amount of a substance decaying exponentially with a half-life can be modeled using the formula A = A₀ * 2^(-t / h), where A is the amount remaining after time t, A₀ is the initial amount of substance, t is the time elapsed, and h is the half-life of the substance. Using the fact that initially there were 12 grams of the substance, and after 2 hours there were 7 grams, we can solve for the half-life h. Substituting the values into the equation 7 = 12 * 2^(-2 / h) and solving, we get that h is approximately 4.145 hours. Finally, we can use the formula A = A₀ * 2^(-t / h) to find the amount of substance remaining after 3 hours. Plugging in A₀ = 12, t = 3, and h ≈ 4.145, we get A ≈ 5.33 grams. Rounding to the nearest hundredth, we conclude that approximately 5.33 grams of the substance will remain after 3 hours.

The value of the population standard deviation necessary to produce a standard error of 3 points is 18 points. The value of the population standard deviation necessary to produce a standard error of 12 points is 72 points. The value of the population standard deviation necessary to produce a standard error of 2 points is 12 points.

To calculate the value of the population standard deviation (σ) necessary to produce each of the following standard error values for a sample of n = 36 scores, we can use the formula:

σM = σ / √n
where σM is the standard error of the mean, σ is the population standard deviation, and n is the sample size.

1. If σM = 12 points, then:
12 = σ / √36
12 = σ / 6
σ = 12 x 6
σ = 72 points

Therefore, the value of the population standard deviation necessary to produce a standard error of 12 points is 72 points.

2. If σM = 3 points, then:
3 = σ / √36
3 = σ / 6
σ = 3 x 6
σ = 18 points

Therefore, the value of the population standard deviation necessary to produce a standard error of 3 points is 18 points.

3. If σM = 2 points, then:
2 = σ / √36
2 = σ / 6
σ = 2 x 6
σ = 12 points

Therefore, the value of the population standard deviation necessary to produce a standard error of 2 points is 12 points.

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The function y =[tex](3/2) x^2[/tex] indeed satisfies the differential equation [tex]dy/dx = x 1.[/tex]

To check if [tex]y = 1/2 x^2 x 3[/tex]satisfies the differential equation dy/dx = x 1, we need to find the first derivative of y with respect to x and then compare it to the given dy/dx expression.

Given y = 1/2 x^2 x 3, we can rewrite it as[tex]y = (3/2) x^2.[/tex]

Now, let's find the first derivative of y with respect to x:

[tex]dy/dx = d(3/2 x^2)/dx = 3x[/tex]
Now we compare this with the given [tex]dy/dx = x 1. Since 3x = 3x * 1[/tex], the function y = (3/2) x^2 indeed satisfies the differential equation dy/dx = x 1.

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The set of parameters that would give this person the worst grade on the exam relative to others is µ = 70 and σ = 5. This can be found using z-score. The correct option is option c).

To determine which set of parameters would give this person the worst grade on the exam relative to others, we need to find the z-score for the score of 65 under each set of parameters and see which one is the lowest. The z-score is a measure of how many standard deviations a particular value is from the mean.

The formula for calculating the z-score is:

z = (x - µ) / σ

where x is the score, µ is the mean, and σ is the standard deviation.

a. µ = 60 and σ = 5

z = (65 - 60) / 5 = 1

b. µ = 70 and σ = 10

z = (65 - 70) / 10 = -0.5

c. µ = 70 and σ = 5

z = (65 - 70) / 5 = -1

d. µ = 60 and σ = 10

z = (65 - 60) / 10 = 0.5

The lowest z-score is -1, which corresponds to option c. This means that most people scored higher than 65, and those who scored lower did so by a smaller margin.

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Out of the given options, the task that is not a likely task of descriptive statistics is "estimating unknown parameters."

Descriptive statistics is a branch of statistics that deals with the collection, analysis, and interpretation of data. It involves summarizing and presenting data in a meaningful way using measures of central tendency, variability, and other statistical tools.

This task is usually carried out in inferential statistics, which involves drawing conclusions about a population based on a sample.

Descriptive statistics, on the other hand, is focused on describing and summarizing the characteristics of a sample or population, rather than making inferences about it.

Therefore, while summarizing a sample, making visual displays of data, and presenting measures of central tendency and variability are all common tasks in descriptive statistics, estimating unknown parameters is not typically a part of descriptive statistics.

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Each point (x, y) on the graph of h(x) becomes the point (x - 3, y - 3) on v(x).

Each point (x, y) on the graph of h(x) becomes the point (x + 3, y + 3) on w(x).

In Mathematics and Geometry, the translation a geometric figure or graph to the left simply means subtracting a digit from the value on the x-coordinate of the pre-image;

g(x) = f(x + N)

On the other hand, the translation a geometric figure to the right simply means adding a digit to the value on the x-coordinate (x-axis) of the pre-image;

g(x) = f(x - N)

Since the parent function is v(x) = h(x + 3), it ultimately implies that the coordinates of the image would created by translating the parent function to the left by 3 units.

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Answer:

To do a full function study of y = x^4 - 8x^2 - 9, we need to determine the domain, intercepts, symmetry, asymptotes, intervals of increase and decrease, local extrema, and concavity.

Domain:

Since the function is a polynomial, it is defined for all real numbers. Therefore, the domain is (-∞, ∞).

x-Intercepts:

To find the x-intercepts, we set y = 0 and solve for x:

x^4 - 8x^2 - 9 = 0

We can factor the left-hand side to get:

(x^2 - 9)(x^2 + 1) = 0

This gives us x = ±√9 = ±3 as the x-intercepts.

y-Intercept:

To find the y-intercept, we set x = 0:

y = 0^4 - 8(0^2) - 9 = -9

Therefore, the y-intercept is (0, -9).

Symmetry:

The function is an even-degree polynomial, which means it has rotational symmetry of order 2 about the origin.

Asymptotes:

There are no vertical or horizontal asymptotes for this function.

Intervals of Increase and Decrease:

To find the intervals of increase and decrease, we need to find the critical points of the function by taking the first derivative and setting it equal to zero:

y' = 4x^3 - 16x = 0

Solving for x, we get x = 0 or x = ±√4 = ±2. Therefore, the critical points are (-2, 43), (0, -9), and (2, 43). We can use the second derivative test to determine that (-2, 43) and (2, 43) are local minima and (0, -9) is a local maximum.

The function increases on the intervals (-∞, -2) and (2, ∞) and decreases on the interval (-2, 2).

Local Extrema:

The local minimum points are (-2, 43) and (2, 43), and the local maximum point is (0, -9).

Concavity:

To determine the concavity of the function, we take the second derivative:

y'' = 12x^2 - 16

Setting y'' equal to zero, we get x = ±√4/3. Since y'' is positive for x < -√4/3 and x > √4/3, and negative for -√4/3 < x < √4/3, we have a point of inflection at x = -√4/3 and x = √4/3.

Plotting the Graph:

We can now use all of the information we have gathered to sketch the graph of y = x^4 - 8x^2 - 9. The graph has rotational symmetry of order 2 about the origin, and it passes through the points (-3, 0), (0, -9), and (3, 0). It has local minimum points at (-2, 43) and (2, 43) and a local maximum point at (0, -9). It changes concavity at x = -√4/3 and x = √4/3. Here is a rough sketch of the graph:

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Step-by-step explanation:

We can prove the statement by mathematical induction.

Base Case: For n = 0, we have 9n - 3n = 1, which is divisible by 6, since 1 = 6*0 + 1.

Inductive Step: Assume that 6 divides 9k - 3k for some non-negative integer k. We need to show that 6 also divides 9(k+1) - 3(k+1).

Starting with 9(k+1) - 3(k+1), we can simplify it as follows:

9(k+1) - 3(k+1) = 9k + 9 - 3k - 3

= (9k - 3k) + (9 - 3)

= 6k + 6

Since 6 divides both 6k and 6, it also divides their sum, 6k + 6. Therefore, we have shown that 6 divides 9(k+1) - 3(k+1).

By the principle of mathematical induction, we can conclude that 6 divides 9n - 3n for all non-negative integers n.

Answer:  The store can sell 451 packs of socks.

Step-by-step explanation:  To find the number of packs of socks the store can sell, we need to divide the total number of socks by the number of socks in each pack.

Since each pack contains 3 pairs of socks, or 6 individual socks, we can find the number of packs by dividing the total number of socks by 6:

1353 socks ÷ 6 socks per pack = 225.5 packs

However, since we can't sell a fraction of a pack, we need to round up to the nearest whole number. Therefore, the store can sell 451 packs of socks.

Share Prompt

Using a trigonometric relation we can see that the value of x is 3,549.3 ft

We can see that we have a right triangle, where x is the hypotenuse.

We know one angle of the triangle and the opposite cathetus of said angle.

Then we need to use the trigonometric relation:

sin(a) = (opposite cathetus)/hypotenuse.

Replacing the things that we know we will get.

sin(25°) = 1500ft/x

Solving that for x we will get:

x = 1500ft/sin(25°)

x = 3,549.3 ft

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Answer:

(-2,-1)

Step-by-step explanation:

see photo

The statement " An example of continuous data would be the numbers on baseball player jerseys" is false because the numbers on baseball player jerseys represent a finite set of distinct values, which makes them an example of discrete data, not continuous data.

Continuous data is data that can take on any value within a range or interval. This means that the data can be measured and expressed as a decimal or a fraction, and there are an infinite number of possible values within the range. For example, the height of a person can be any value between 5 feet and 6 feet, including all the possible fractions or decimals in between.

On the other hand, discrete data is data that can only take on certain distinct values. These values cannot be measured or expressed as a decimal or a fraction. Examples of discrete data include the number of children in a family, the number of students in a classroom, or the number of books on a shelf.

In the case of baseball player jerseys, the numbers are assigned to players based on a finite set of integers (typically 0 to 99), and there are no fractional or decimal values in between. Therefore, the numbers on baseball player jerseys are an example of discrete data, not continuous data.

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f(x) = sqrt(x^2 + x)

Yes, f(x) is O(x^2) because sqrt(x^2 + x) is dominated by x when x is sufficiently large.

f(x) = 17x^(11)

Yes, f(x) is O(x^2) because 17x^11 is dominated by x^2 when x is sufficiently large.

f(x) = x^(2/1000)

Yes, f(x) is O(x^2) because x^(2/1000) is dominated by x^2 when x is sufficiently large.

f(x) = x^42

Yes, f(x) is O(x^2) because x^42 is dominated by x^2 when x is sufficiently large.

f(x) = ⌊x⌋⋅⌈x⌉

Yes, f(x) is O(x^2) because ⌊x⌋⋅⌈x⌉ is bounded above by x^2 when x is sufficiently large.

f(x) = log(2x)

No, f(x) is not O(x^2) because log(2x) grows much more slowly than x^2 when x is sufficiently large.

f(x) = xlog(x)

No, f(x) is not O(x^2) because xlog(x) grows much more slowly than x^2 when x is sufficiently large.

f(x) = sqrt(x^2 + x)

Yes, f(x) is O(x^2) because sqrt(x^2 + x) is dominated by x when x is sufficiently large.

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The image of triangle EFG after rotation 90 degrees countercloeckwise is shown below.

We know that when we rotate a point P(x, y) 90 degrees counterclockwise about the origin then the coordinates of point after rotation becomes (-y, x)

Here the coordinates of the triangle EFG are:

E(4, -8)

F(4, -1)

G(3, -9)

We need to rotate triangle EFG 90 degrees counterclockwise.

With the help of above statement the coordinates of rotated triangle would be,

E'(8, 4)

F'(1, 4)

G'(9,3)

The transformed triangle is shown below.

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Number of Folds | Style 1 Number of Sections | Style 2 Number of Sections:

From the table, the pattern relating the number of folds to the number of sections for Style 1 (accordion-style) is that the number of sections doubles with each additional fold. In other words, the number of sections is equal to 2 raised to the power of the number of folds. For Style 2 (half-folds), the pattern is less clear, but we can observe that the number of sections increases more rapidly with each additional fold than it does for Style 1. This is likely due to the fact that each fold in Style 2 creates two new sections, whereas in Style 1, each fold only creates one new section.

The two different folded styles of paper produce different results because they create different shapes and arrangements of rectangular sections when folded. In Style 1 (accordion-style), each fold creates a single new section that is added to the end of the folded paper. The result is a long, thin strip of paper with rectangular sections stacked on top of each other. In contrast, Style 2 (half-folds) creates a zig-zag pattern of rectangular sections that are stacked on top of each other. Each fold in Style 2 creates two new rectangular sections, which allows the number of sections to increase more rapidly than in Style 1. This difference in the way the paper is folded and the resulting shapes and arrangements of rectangular sections leads to different patterns in the number of sections as the number of folds increases.

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The probability that the average amount of paid time lost during a three-month period for the 100 blue-collar workers will exceed 1.5 days is 0.0228.

Since the sample size n = 100 is sufficient, we can apply the central limit theorem to roughly approximate the distribution of the sample mean.

Let X represent the total paid time a single blue-collar worker missed during a three-month period. Given that the population mean is 1.3 days and the population standard deviation is 1.0 days, X N(1.3, 1.02) follows.

Let Y be the sample mean of X for a sample of 100 blue-collar workers selected at random. So, according to the central limit theorem, Y = N(1.3, 1.02/100).

We are looking for P(Y > 1.5). By standardized Y, we obtain:

Z is defined as (Y - ) / (n /√(n)) = (1.5 - 1.3) / (1.0 / √(100)). = 2

The probability of the event that average amount of the paid time loss is 0.0288.

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Complete question - In an article in the Journal of Management, Joseph Martocchio studied and estimated the costs of employee absences. Based on a sample of 176 blue-collar workers, Martocchio estimated that the mean amount of paid time lost during a three-month period was 1.3 days per employee with a standard deviation of 1.0 days. Martocchio also estimated that the mean amount of unpaid time lost during a three-monthperiod was 1.4 day per employee with a standard deviation of 1.2 days.

Suppose we randomly select a sample of 100 blue-collar workers. Based on Martocchio's estimates:

(a)What is the probability that the average amount of paid time lost during a three-month period for the 100 blue-collar workers will exceed 1.5 days?

The differential of arc length for the curve C parametrized by r(t) is given by:

ds = sqrt((dx/dt)² + (dy/dt)²) dt

where x =  [tex]e^t[/tex]² and y = ln(t+1).

Taking the derivatives, we get:

dx/dt = 2t ([tex]e^t[/tex])²
dy/dt = 1/(t+1)

Substituting into the formula, we get:

ds = sqrt((2t [tex]e^t[/tex]²)² + (1/(t+1))²) dt

Simplifying, we get:

ds = sqrt(4t²e²t² + 1/(t+1)²) dt

Therefore, the differential of arc length for the curve C parametrized by r(t) is:

ds = sqrt(4t²e²t² + 1/(t+1)²) dt.

This formula allows us to calculate the length of the curve C between two points on the curve by integrating the differential of arc length between the corresponding values of t.

The formula shows that the length of the curve increases as t increases, with the rate of increase depending on the values of t and e.

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We will need 7 cubic feet of dirt to fill the garden box completely.

The formula for the volume of a rectangular box is:
Volume = Length × Width × Height

In this case, the dimensions of the garden box are:
Length = 3 1/2 feet
Width = 4 feet
Height = 1/2 foot
First, convert the mixed numbers to improper fractions:
Length = (3 × 2 + 1)/2 = 7/2 feet
Now, multiply the dimensions together:
Volume = (7/2) × 4 × (1/2)
Simplify the fractions:
Volume = (7 × 4 × 1) / (2 × 2) = 28 / 4
Finally, divide to find the volume in cubic feet:
Volume = 28 ÷ 4 = 7 cubic feet.

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Answer:

40 miles

Step-by-step explanation:

If Nicole has driven 20 miles and this is only half the distance, then the total length of her drive would be 40 miles.

We can determine this with a simple algebraic equation:

Let x be the total length of her drive.

We know that Nicole has already driven one-half of the distance, which can be represented as:

20 = 1/2x

Multiplying both sides by 2, we get:

40 = x

Therefore, the total length of Nicole's drive is 40 miles.

The statement "The radius of a star can be indirectly determined if the star's distance and luminosity are known." is true because the radius of a star can be calculated using the Stefan-Boltzmann Law.

The Stefan-Boltzmann Law can be used to determine a star's radius. This law states that the luminosity of a star (the total amount of energy it emits in a given time) is proportional to the fourth power of its radius. Therefore, if the distance and luminosity of a star are known, its radius can be calculated by rearranging the equation.

This equation can be used to calculate the radius of a star even if its size cannot be directly measured. The equation is:

Radius = (L/4πσT⁴[tex])^{1/2}[/tex]

Where L is the luminosity of the star, σ is the Stefan-Boltzmann constant, and T is the temperature of the star.

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Answer:

simplifying

Step-by-step explanation:

To solve this problem, we can use the principle of inclusion-exclusion.

First, let's find the total number of ways to select n students from a class of 5n:

Total ways = (5n choose n) = (5n)! / (n!*(5n-n)!) = (5n)! / (n!*(4n)!)

We can calculate the curvature k as:

k = |dT/ds| / |dr/ds|

[tex]= |d^2 r(s)/ds^2| / |dr/ds|^3[/tex]

To find the curvature k of a curve given by the vector-valued function r(s), where s is the arc length parameter, we use the following formula:

k = |dT/ds| / |dr/ds|

where T(s) is the unit tangent vector and r'(s) is the velocity vector.

To find T(s), we differentiate r(s) with respect to s:

T(s) = dr(s)/ds

Then, we normalize T(s) to obtain the unit tangent vector:

T(s) = dr(s)/ds / |dr(s)/ds|

Next, we differentiate T(s) with respect to s to obtain the unit normal vector N(s):

[tex]N(s) = d^2 r(s)/ds^2 / |d r(s)/ds|[/tex]

Finally, we can calculate the curvature k as:

k = |dT/ds| / |dr/ds|

[tex]= |d^2 r(s)/ds^2| / |dr/ds|^3[/tex]

So, to find the curvature k of the curve given by the vector-valued function r(s), we need to calculate r(s), dr(s)/ds, and[tex]d^2 r(s)/ds^2[/tex] and plug them into the above formula.

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It will take approximately 67 months to have $10,000 to buy a boat with monthly deposits of $140 at a 3% monthly compounded interest rate.

To determine how long it will take to save $10,000 with monthly deposits of $140 at a 3.0% interest rate compounded monthly, we'll use the future value of a series formula:
FV = P * (((1 + r)^n - 1) / r)
Where:
FV = future value of the series ($10,000)
P = monthly deposit ($140)
r = interest rate per period (0.03 / 12)
n = number of periods (number of months)
Rearrange the formula to solve for n:
n = ln((FV * r / P) + 1) / ln(1 + r)
Plug in the values:
n = ln((10,000 * (0.03 / 12) / 140) + 1) / ln(1 + (0.03 / 12))
n ≈ 62.1
Since we need to round up to the next whole month, it will take approximately 63 months to save $10,000 to buy the boat.

It will take approximately 67 months to have $10,000 to buy a boat. Using the formula for compound interest, we can calculate the future value of monthly deposits of $140 at a rate of 3% compounded monthly:
FV = PMT * ((1 + r)^n - 1) / r
Where:
PMT = $140 (monthly deposit)
r = 0.03/12 (monthly interest rate)
n = number of months
We want to find the value of n that gives us a future value of $10,000:
$10,000 = $140 * ((1 + 0.03/12)^n - 1) / (0.03/12)
Simplifying and solving for n, we get:
n = log(1 + ($10,000 * 0.03/12 / $140)) / log(1 + 0.03/12)
n ≈ 66.8
Since we can't have fractional months, we round up to the next higher month:
n ≈ 67
Therefore, it will take approximately 67 months to have $10,000 to buy a boat with monthly deposits of $140 at a 3% monthly compounded interest rate.

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Sample standard deviation is approximately 0.6129.

We add all the numbers and divide by the sample size:

(0.1 + 0 - 0.3 - 1.4 + 0) / 5 = -0.32/5 = -0.064

Therefore, the sample mean is -0.064.

To find the sample variance, we need to first find the deviations of each measurement from the sample mean. We subtract the sample mean from each measurement to get:

0.1 - (-0.064) = 0.164

0 - (-0.064) = 0.064

-0.3 - (-0.064) = -0.236

-1.4 - (-0.064) = -1.336

0 - (-0.064) = 0.064

Then, we square each deviation:

0.164² = 0.026896

0.064² = 0.004096

(-0.236)² = 0.055696

(-1.336)² = 1.787296

0.064² = 0.004096

We take the average of these squared deviations to get the sample variance:

(0.026896 + 0.004096 + 0.055696 + 1.787296 + 0.004096) / 5 = 0.375416

Therefore, the sample variance is 0.375416.

To find the sample standard deviation, we take the square root of the sample variance:

sqrt(0.375416) = 0.6129

Therefore, the sample standard deviation is approximately 0.6129.

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The 5-point DFT of the sequence Y(k) is [15 -2.5 + 3.4j -2.5 + 0.81j -2.5 - 0.81j -2.5 - 3.4j]. So, the correct answer is 1).

We can find the 5-point DFT of y(n) using the formula

Y(k) = sum_{n=0}^{4} y(n) exp(-2piikn/5), k = 0,1,2,3,4

Substituting the values of y(n) = {1, 2, 3, 4, 5}, we get

Y(0) = 1 + 2 + 3 + 4 + 5 = 15

Y(1) = 1 + 2exp(-2pii/5) + 3exp(-4pii/5) + 4exp(-6pii/5) + 5exp(-8pii/5) = -2.5 + 3.4j

Y(2) = 1 + 2exp(-4pii/5) + 3exp(-8pii/5) + 4exp(-12pii/5) + 5exp(-16pii/5) = -2.5 + 0.81j

Y(3) = 1 + 2exp(-6pii/5) + 3exp(-12pii/5) + 4exp(-18pii/5) + 5exp(-24pii/5) = -2.5 - 0.81j

Y(4) = 1 + 2exp(-8pii/5) + 3exp(-16pii/5) + 4exp(-24pii/5) + 5exp(-32pii/5) = -2.5 - 3.4j

Therefore, the 5-point DFT of the sequence Y(k) is [15, -2.5 + 3.4j, -2.5 + 0.81j, -2.5 - 0.81j, -2.5 - 3.4j], which is option 1.

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Answer:

3400

Step-by-step explanation:

3.4 x 1000 =3400

to go from km a big unit to meters a smaller unit, you multiply by 1000

Answer:

Step-by-step explanation:

A. Let x be the mass of 1 slice of cheese.

B. The difference in the masses of 1 slice of cheese and 1 cracker is:

x - 3.25 grams

C. Since one package contains 16 slices of cheese, the total mass of the package is:

16x

According to the problem, the mass of one cracker is 18 grams less than the mass of one slice of cheese. Therefore, we can write:

x - 18 = 3.25 + m/16

where m is the mass of the package of 16 slices of cheese.

Simplifying the equation:

x = 3.25 + m/16 + 18

x = m/16 + 21.25

This equation represents the relationship between the masses of 1 cracker and 1 slice of cheese in terms of the mass of a package of 16 slices of cheese.

Answer:

Step-by-step explanation:

Answer: 260

Step-by-step explanation:

Use proportions:

65/25 = x/100

cross multiply the proportions:

25x = 6500

solve your equation:

x = 260

The number is 260.

Let's start by finding the number we're working with.

We know that 25% of the number is 65, so we can set up an equation:

0.25x = 65

To solve for "x", we can divide both sides of the equation by 0.25:

x = 65 / 0.25

x = 260

So the number we're working with is 260.

Next, we need to find 40% of the same number:

0.40(260) = 104

Now we can use this information to find 15% of the same number:

We can set up a proportion:

40% is to 104 as 15% is to x

0.40/104 = 0.15/x

To solve for "x", we can cross-multiply:

0.40x = 104(0.15)

0.40x = 15.6

x = 39

So 15% of the same number is 39.