The singer sold 512 music downloads.
What is equation?A mathematical definition of an equation is a claim that two expressions are equal when they are joined by the equals sign ("="). For illustration, 2x - 5 = 13. 2x - 5 and 13 are expressions in this case. These two expressions are joined together by the sign "=".
Let's use the following variables:
CD = the number of CD singles sold
DL = the number of music downloads sold
From the problem, we know the following:
CD + DL = total number of singles sold
CD = 456
The profit from selling CD singles is 35p = £0.35 per CD single
The profit from selling music downloads is 17p = £0.17 per music download
The total profit is £246.64
Using the information above, we can set up two equations based on the profits earned from selling CD singles and music downloads:
0.35 * CD = profit from CD sales
0.17 * DL = profit from download sales
And we know that the sum of these two profits equals the total profit:
0.35 * CD + 0.17 * DL = 246.64
Substituting CD = 456, we get:
0.35 * 456 + 0.17 * DL = 246.64
Simplifying this equation, we get:
159.6 + 0.17 * DL = 246.64
0.17 * DL = 87.04
DL = 512
Therefore, the singer sold 512 music downloads.
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Write an equivalent expression.
(x+7)+2
Answer:
The answer is x+9, I really hope this helps (:
In the figure below, point O is the center of the circle and mRQ=35° . What is m∠POQ ? A. 125° B. 135° C. 70° D. 145°
Answer:
Step-by-step explanation:
A. 125
CAN SOMEONE HELP WITH THIS QUESTION?
The rate of change of the area outside the circle but inside the square is 1 m² per minute.
What is area?Area is the measure of the size of a two-dimensional (2D) shape or planar region. It is expressed in terms of square units, such as square metres (m2) and square feet (ft2). The area of a shape is the total space contained within its boundaries.
To answer this question, we need to find out the area outside the circle but inside the square. This can be done by subtracting the area of the circle from the area of the square.
The area of the circle is equal to πr², where r is the radius of the circle. In this case, the radius is 3 meters, so the area of the circle is π×32 = 28.27 m².
The rate of change of the area outside the circle but inside the square is 1 m²per minute.
The area of the square is equal to side², where side is the length of one side of the square. In this case, the side is 16 meters, so the area of the square is 162 = 256 m².
Subtracting the area of the circle from the area of the square gives us the area outside the circle but inside the square. This is 256 - 28.27 = 227.73 m².
Now, we know the area outside the circle but inside the square, and we know that the radius of the circle is increasing at a rate of 1 meter per minute and the sides of the square are increasing at a rate of 2 meters per minute. This means that the area outside the circle but inside the square is increasing at a rate of (2 - 1) = 1 m²per minute.
Therefore, the rate of change of the area outside the circle but inside the square is 1 m² per minute.
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Darlena has started taking photos at amateur dog racing events, later offering the photos for sale to the dog owners by email. The prices she has charged per photo at each of her first three events, and the corresponding number of photos sold and total revenue raised, appear in the table below.
Treating revenue as a function of the number of photos sold, a graph of the three data points is also shown. If she uses quadratic regression to fit a curve to the data, what number of photos sold and what price per photo will maximize her revenue?
The maximum revenue is achieved when she sells 33 photos at a price of 25 per photo.
Using quadratic regression, [tex]y = ax^2 + bx + c[/tex]
where a, b and c are constants and x is the independent variable we can determine the equation of the curve that best fits the data. The equation will be in the form of[tex]y = ax^2 + bx + c[/tex], where y is the revenue, x is the number of photos sold, and a, b, and c are constants. The constants can be determined by solving the system of equations formed by the three data points.
After solving for the constants, we can determine the maximum revenue by finding the vertex of the curve. The vertex is located at x = -b/2a, and the corresponding revenue is[tex]y = ax^2 + bx + c[/tex]. Plugging in the values for a, b, and c, we can calculate that the maximum revenue is achieved when she sells 33 photos at a price of 25 per photo.
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Complete question
Darlena has started taking photos at amateur dog racing events, later offering the photos for sale to the dog owners by email. The prices she has charged per photo at each of her first three events, and the corresponding number of photos sold and total revenue raised, appear in the table below. Treating revenue as a function of the number of photos sold, a graph of the three data points is also shown. If she uses quadratic regression to fit a curve to the data, what number of photos sold and what price per photo will maximize her revenue?
Find the value of each variable.
The values of the variables in the semicircle shown are:
x = 63 degrees; y = 90 degrees.
What is the Angle Inscribed in a Semicircle Theorem?A semi-circle is exactly half of a full circle and has a measurement of 180 degrees; the two endpoints of the diameter form the endpoints of the semi-circle. If an angle is enclosed inside a semi-circle, the angle formed measures 90 degrees.
Therefore, it means the value of the variable, y = 90 degrees.
Thus, using the triangle sum theorem, we have:
x = 180 - 90 - 27
x = 63 degrees.
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Pls answer today and fast!!!! Use the tools below to make a triangle with angle measures or 60 degrees, 40 degrees, and 80 degrees.
An angle is a geometric figure formed by two rays or line segments that share a common endpoint, called the vertex. Angles are measured in degrees or radians and are typically denoted by symbol ∠ followed by the name of the vertex, like ∠ABC.
What is the Angle?The size of angle is determined by amount of rotation needed to bring one of rays or line segments into coincidence with others.
Angles can be acute (less than 90 degrees), right (exactly 90 degrees), obtuse (greater than 90 degrees but less than 180 degrees), straight (exactly 180 degrees), or reflex (greater than 180 degrees).
Angles are fundamental to geometry and have many applications in physics, engineering, and other fields.
This is because the sum of the angles in a triangle must always be 180°, and 40° + 60° + 80° = 180°.
However, the angles do not satisfy the conditions of the triangle inequality theorem, which states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.
Therefore, It is not possible to construct a triangle with angle measures of 40°, 60°, and 80°.
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Describe the possible values of x if the area of the rectangle is at least 40 square inches
The value of x is 32.
Describe Rectangle?A rectangle is a quadrilateral (a four-sided polygon) with four right angles (90-degree angles) and opposite sides that are parallel and congruent (the same length). The opposite sides of a rectangle are also perpendicular to each other, meaning they intersect at a 90-degree angle.
The rectangle is a special case of a parallelogram, where all the angles are right angles. A square is also a special type of rectangle, where all the sides are congruent.
We can use the formula for the area of a rectangle, which is:
Area = Length x Width
Substituting the given values, we get:
40 = (5/8)x + 5 x 4
Simplifying, we get:
40 = (5/8)x + 20
Subtracting 20 from both sides, we get:
20 = (5/8)x
Multiplying both sides by 8/5, we get:
x = 32
Therefore, the value of x is 32.
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PLs help Thank u!!!!!!!!!!!!!!!!!!!!!!!!
Using a trigonometric relation, we can see that the values of x and y are:
y = 25.98
x = 15
How to get the values of x and y?Here we can see a right triangle, where we know the interior angles and the length of the hypotenuse.
To get the lengths of the legs, we can use trigonometric relations, like:
cos(a) =(adjacent cathetus)/hypotenuse.
For example, if we want to find y, then the angle at which this side is adjacent is the 30° one, now replacing the known values in the formula we will get:
cos(30°) = y/30
cos(30°)*30 = y = 25.98
And to get the value of x, we should use the 60°angle, so:
cos(60°) = x/30
30*cos(60°) = x = 15
These are the two lengths we wanted to get.
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The graph shows g(x) = x2 − 9x + 20. graph of parabola falling from the left, passing through 3 comma 2 to about 4 and one half comma negative one fourth, and rising to the right, passing through 6 comma 2 What are the x-intercepts of g(x)? (4.5, 0) and (5, 0) (0, 4.5) and (0, 5) (0, 5) and (0, 4) (5, 0) and (4, 0)
Parabola intersects x-axis at two points: (-5,0) and (-4,0)
What does a parabola actually mean?
Each point on a parabola with a U-shape is equally spaced from both the focus, a fixed point, and the directrix, a fixed line. As the topic of conic sections depends heavily on the parabola, all of the parabola-related concepts are covered here.
The x-intercepts of a parabola are where the parabola intersects the x-axis on its graph. There are a number of ways to find the x-intercepts of a parabola, and each one is usually specific to each situation.
In the case, when you are given the graph, the easiest way to find x-intercepts is to identify points at which parabola intersects the x-axis.
From your graph, parabola intersects x-axis at two points: (-5,0) and (-4,0)
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Determine whether the given ordered pairs listed are solutions of the system of linear equations.
2x + y = 5
− 3x + 5y = − 1
(a) (b)(1,3) (2,1)
(a) Is (1,3) a solution?
(1, 3) is not a solution to the system of linear equations and (2,1) is a solution to the system of linear equations.
What are linear equations?
To check if the ordered pair (1, 3) is a solution to the system of linear equations:
2x + y = 5 ...(1)
−3x + 5y = −1 ...(2)
Substitute x = 1 and y = 3 in equations (1) and (2), respectively:
2(1) + 3 = 5 ...(1)
−3(1) + 5(3) = −1 ...(2)
Simplifying these equations:
2 + 3 = 5 (true)
−3 + 15 = −1 (false)
Therefore, (1, 3) is not a solution to the system of linear equations.
To check if the ordered pair (2,1) is a solution to the system of linear equations:
2x + y = 5 ...(1)
−3x + 5y = −1 ...(2)
Substitute x = 2 and y = 1 in equations (1) and (2), respectively:
2(2) + 1 = 5 ...(1)
−3(2) + 5(1) = −1 ...(2)
Simplifying these equations:
4 + 1 = 5 (true)
−6 + 5 = −1 (true)
Therefore, (2,1) is a solution to the system of linear equations.
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IT A MULTI-STEP PROBLEM HELP! 6 PARTS TO IT!!! IM GOING TO FAIL!! CAN PLEASE DO IT STEP BY STEP
a. The cost of one large pizza with one topping is $13.50. To purchase one large and five medium pizzas, we would need to buy one large pizza at regular price and five medium pizzas at the discounted price. The cost of the large pizza is $13.50, and the cost of each medium pizza is $6.25. Therefore, the total cost would be:
Total cost = Cost of large pizza + Cost of 5 medium pizzas
Total cost = $13.50 + ($6.25 x 5)
Total cost = $13.50 + $31.25
Total cost = $44.75
Therefore, it would cost $44.75 to purchase one large pizza and five medium pizzas.
b.Number of medium pizzas Total cost
0 | $13.50
1 | $19.75
2 | $26.00
3 | $32.25
4 | $38.50
c. Let "m" be the number of medium pizzas. Then the total cost of purchasing one large pizza with one topping and m medium pizzas can be represented as:
Total cost = 13.50 + 6.25m
d. If you have a total of $100 and purchase one large pizza, you would have $100 - $13.50 = $86.50 left to spend on medium pizzas. The cost of each medium pizza is $6.25. Therefore, you can buy:
Number of medium pizzas = $86.50 ÷ $6.25 = 13.84
Since you cannot buy a fraction of a pizza, you can only buy 13 medium pizzas with $86.50.
e. The area of a pizza is given by the formula A = πr^2, where A is the area and r is the radius. The area of a large pizza is:
A = πr^2
A = 3.14 x 8^2
A = 3.14 x 64
A = 200.96
The area of a medium pizza is:
A = πr^2
A = 3.14 x 5^2
A = 3.14 x 25
A = 78.5
Therefore, the total area of one large pizza and five medium pizzas is:
Total area = Area of large pizza + (Area of medium pizza x 5)
Total area = 200.96 + (78.5 x 5)
Total area = 200.96 + 392.5
Total area = 593.46
Rounding to the nearest inch, the total area of pizza is 593 square inches.
f. To calculate the cost per square inch of pizza, we need to divide the total cost of the pizzas by the total area of the pizzas. The total cost of one large pizza and five medium pizzas is $44.75, and the total area is 593 square inches. Therefore, the cost per square inch of pizza is:
Cost per square inch = Total cost / Total area
Cost per square inch = $44.75 / 593
Cost per square inch = $0.08 (rounded to the nearest cent)
Therefore, the cost per square inch of pizza is 8 cents.
Solve the triangle MNO (find m<O and the lengths of sides m and n).
The measure of angle O is 56 and the value of m and n are 8.1 in and 14.5 in respectively.
What is trigonometric ratio?Trigonometric Ratios are defined as the values of all the trigonometric functions based on the value of the ratio of sides in a right-angled triangle. The longest side is hypotenuse and it is the side facing the right angle. The other two sides are opposite and adjascent.
sin(tetha) = opp/hyp
cos(tetha) = adj/hyp
tan,(tetha) = opp/adj
angle O = 180-(90+34)
= 180- 124
= 56°
To find m,
Tan 34 = m/12
m = Tan34 × 12
m = 8.1 in
using Pythagoras theorem to find n,
n= √8.1²+12²
n = √65.61+144
n = √209.61
= 14.5 in
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A college professor claims that students who major in engineering in college score higher on standardized test then students who major in ancient history. He randomly selected 50 students from each subject and gave them this assignment the results of which are shown here.
See chart and answer choices in photo!
Please answer quickly, tysm!
The statement which best describe the correct null and alternative hypotheses, the test statistic, and conclusion at a significance level of 0.05 is:
D. H₀: μ₁ = μ₂ H₁: μ₁ < μ₂.
test statistic, t = -1.5625.
conclusion: fail to reject the null hypothesis μ₁ = μ₂.
How to determine and write the null and alternative hypotheses?Based on the information provided, the appropriate null hypothesis and alternative hypothesis would be represented by the following mathematical expression:
H₀: μ₁ - μ₂ ≤ 0; μ₁ = μ₂
H₁: μ₁ - μ₂ < 0; μ₁ < μ₂.
For the critical value, we have:
Critical probability (p*) = 1 - α
Critical probability (p*) = 1 - 0.05
Critical probability (p*) = 0.9500.
Based on the distribution table for probabilities, a value that corresponds to 0.9500 can be calculated as follows;
Zα = 1.6 + 0.05 = 1.65.
For an upper-tailed test, the critical value is given by;
Z_{critical} = 1.65.
Therefore, if Z_{test} > 1.65; reject null hypothesis (H₀) and if Z_{test} < 1.65; fail to reject null hypothesis (H₀).
Next, we would determine the test statistic:
[tex]Z_{test} = \frac{116 -121 -0}{\sqrt{\frac{16^2}{50} +\frac{16^2}{50} } } \\\\Z_{test} = \frac{-5}{\sqrt{\frac{256}{50} +\frac{256}{50} } }\\\\Z_{test} = \frac{-5}{\sqrt{10.24} }[/tex]
Z_{test} = -5/3.2
Z_{test} = -1.5625
In conclusion, we would fail to reject null hypothesis (H₀) since a Z_{test} of -1.5625 is less than a Z_{critical} of 1.65.
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Factor.
f(x) = 6x^2 - 7x+2
Answer: f(x)=(2x−1)(3x−2)
Step-by-step explanation:
Answer:
Step-by-step explanation:
(2x−1)(3x−2)
Select the correct answer.
What is the simplified form of this expression?
(2x + 9) + (11x − 4)
A.
13x + 5
B.
13x + 13
C.
18x
D.
-9x + 5
Answer:
13x+5
Step-by-step explanation:
Here's why
2x+9+11x-4
subtract 4 from 9
2x+5+11x
combine like terms
13x+5
please helo me solve this
Answer:
We use thales theorem
Therfore the answer is 34
Kevin drove 18 1/2 miles in 2/3 hours. If he drove at a constant rate, how far did he travel in one hour
Answer:
27.75 miles
Step-by-step explanation:
(18 1/2 miles) / (2/3 hours) = (37/2 miles) × (3/(2 hours)) = 111/4 miles/hour
111/4 miles/hour = 27.75 miles/hour
Answer: 27.75 miles
Can anyone solve the following two maths?
In conclusion the team took 50 strokes to complete the final 500 meters of the race and at the end of the season, the team's mean split time should be 99 seconds.
How to find?
To find the answer to question 37, we know that the team rowed the final 500 meters in 108 seconds. We also know that they rowed at a rate of 28 strokes per minute during this split. To find out how many strokes they took to complete the final 500 meters, we need to convert the split time to minutes and then multiply by the stroke rate.
First, we convert the split time to minutes:
108 seconds ÷ 60 seconds per minute = 1.8 minutes
Then, we multiply by the stroke rate to find the total number of strokes:
1.8 minutes x 28 strokes per minute ≈ 50 strokes
Therefore, to the nearest whole number, the team took 50 strokes to complete the final 500 meters of the race.
To find the answer to question 38, we need to find the team's mean split time and then reduce it by 10%. The mean split time is found by taking the total race time and dividing by 4, since there are 4 splits in the race.
Total race time = 440 seconds
Mean split time = Total race time ÷ 4 = 110 seconds
To reduce the mean split time by 10%, we multiply it by 0.9:
New mean split time = 110 seconds x 0.9 = 99 seconds
Therefore, at the end of the season, the team's mean split time should be 99 seconds.
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PLEASE HELP ASAP ITS DUE IN AN HOUR
Answer:
[tex]3^2-5[/tex]
Step-by-step explanation:
Given equation:
( 3 - 2^2) + 5
3 - 4 + 5 (Simplify exponent)
-1 + 5 (Solve 3 - 4)
4 (Simplified)
Evaluation
2^2 + 5
4 + 5
9 (not the answer)
3^2 - 5
9-5
4 (answer)
I need help with a problem on my test.
Write an exponential function to model the situation. Tell what each variable represents. A price of $115 increases 9% each month.
Please help
Answer: 1050$
Step-by-step explanation:
im a math teacher
6 7 2 4 6 6 9 5 3 3
Work out the median.
Answer:
5.5
Step-by-step explanation:
The median is the middle number in an ordered ascending/descending list.
The first step is to order the list. In this case I chose to do so in ascending order.
This gets you:
2 3 3 4 5 6 6 6 7 9
In this case there is an even amount of numbers, which means there will be 2 central numbers, 5 and 6.
Averaging these two numbers will get you the median.
(5+6) / 2 = 5.5
which expression is equivalent to the following 3( 8x - 2y + 7 )
Answer:
24x - 6y + 21
Step-by-step explanation:
3( 8x - 2y + 7 )
Multiply each term in the bracket by 3
= (3 x 8x) - ( 3 x 2y) + (3 x 7)
= 24x - 6y + 21
The table shows the data of a random sample of fish that were collected from and later released into a lake.
Type of Fish Bass Eel Gar
Number of Fish 92 56 52
How many eels are estimated to be present if a sample of 1,000 fish is collected from the lake? (1 point)
a
112
b
280
c
320
d
380
Answer: d
Step-by-step explanation: its d
Hunter surveys a random sample of 64 students at his community college and finds that
37.5% of the students saw a film at the local movie theater in the last 30 days. Find a 90% confidence interval for the proportion p of all students at the community college who saw a film at the movie theater in the last 30 days.
We can be 90% confident that the true proportion of all students who saw a film at the movie theater in the last 30 days is between 0.277 and 0.473.
What is proportion?
Proportion is a mathematical term that represents a relationship between two quantities or numbers. It refers to the comparison of one part of a whole to the whole itself.
To find a confidence interval for the proportion p of all students who saw a film at the movie theater, we can use the formula:
CI = p ± z * √(p(1-p)/n)
where p is the sample proportion, n is the sample size, z is the z-score corresponding to the desired level of confidence (90% in this case), and √(p(1-p)/n) is the standard error of the proportion.
First, we need to find the sample proportion p:
p = 37.5% = 0.375
Next, we need to find the z-score corresponding to a 90% confidence level. We can use a z-table or a calculator to find this value. The z-score for a 90% confidence level is 1.645.
Now we can plug in the values into the formula:
CI = 0.375 ± 1.645*√(0.375(1-0.375)/64)
Simplifying:
CI = 0.375 ± 0.098
Therefore, the 90% confidence interval for the proportion of all students who saw a film at the movie theater in the last 30 days is:
CI = (0.277, 0.473)
Hence, we can be 90% confident that the true proportion of all students who saw a film at the movie theater in the last 30 days is between 0.277 and 0.473.
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A triangular bookshelf has a base of 10 inches and 18 inches will the bookshelf fit in the corner of a square living room
No, if fit indicates that the bookcase's sides must be flush with the wall, which means that they must touch the wall and that the bookshelf is correctly positioned in that location.
What are triangles?A triangle is a polygon with three edges and three vertices.
It belongs to the basic geometric shapes.
A triangle having vertices A, B, and C is known as triangle ABC.
Any three locations in Euclidean geometry that are not collinear result in a distinct triangle and a distinct plane.
I've discovered that using the 3:4:5 triangle is the simplest way to determine for sure if an angle is 90 degrees.
This rule states that a triangle is a right triangle even if one of its sides is 3 and the other is 4 if the diagonal connecting its two points measures 5.
So, we must check to see if any of the bookcase's vertices measure 90 degrees because a square room will naturally have corners that do.
We may utilize Pythagorean Theorem to find the solution because every right triangle contains a 90° angle.
Pythagorean The a, b, and c are the legs, and the theorem states that a² + b² = c².
For our bookshelf, 10 and 12 are the legs, and 18 would be the hypotenuse if it were a right triangle as the hypotenuse is always the longest side.
To determine whether the equation is true or false, enter the values.
10² + 12² = 18²
100 + 144 = 324
244 ≠ 324
Thus, the bookshelf does not form a straight angle and cannot be placed in the room's corner.
Therefore, no, if fit indicates that the bookcase's sides must be flush with the wall, which means that they must touch the wall and that the bookshelf is correctly positioned in that location.
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Correct question:
A triangular bookshelf has a base of 10 inches,12 inches, and 18 inches. Will the bookshelf fit in the corner of a square living room?
pls help i dont get this one
Answer:
f(-2) = 0
Step-by-step explanation:
f(x) = (2x+4)/6 is a "rule" or like, directions. It says take your number, times by 2, add 4 and then divide by 6.
f(-2) just means to put -2 in place of x. Do the "rule" or follow the directions on the number -2.
f(x) = (2x+4)/6
f(-2) = (2•-2 + 4)/6
= (-4+4)/6
= 0/6
= 0
So f(-2) = 0
Mr. Jonas's aquarium holds 8 gallons
of water. If he buys another that
holds 1½ times as many gallons,
how many gallons of water does
Mr. Jonas's new tank hold?
After a certain number of years, the value of an investment account is represented by the equation A(t)=10,250(1+r0.4/12)^120 What is the value of the account?
The equation given is A(t) = 10,250(1 + r 0.04/12)^120. To solve for the value of the account, we need to calculate the right side of the equation. First, we need to calculate the exponent of 1+r 0.04/12. This is equal to 120, so the exponent is 120. Next, we need to multiply 10,250 by the exponent of 1+r 0.04/12. This will give us the value of the account. The answer is 1,895,167.50.
3. Assume that there are only 2 commodities and that the utility function is multiplication of the form U = 1÷4qxqy.Find the demand function of the commodity x and y and explain the relationship between price and income in relation to the demand.
Answer:
Step-by-step explanation:
Please help i need it!!!
Which has more kinetic energy, a 5 kg rock hitting a car at 25 m/s or a 10 kg rock hitting a car at 15 m/s? Use the formula kinetic energy = (½)mv². Show your work using the graphical equation tool (Σ button in the toolbar above the text box).
Answer:
Σ Kinetic energy of 5 kg rock hitting car > Σ Kinetic energy of 10 kg rock hitting car
Step-by-step explanation:
We can use the formula for kinetic energy, which is:
Kinetic energy = (1/2) x mass x velocity^2
Let's start by calculating the kinetic energy of the 5 kg rock hitting the car at 25 m/s:
Kinetic energy = (1/2) x 5 kg x (25 m/s)^2
Kinetic energy = 1562.5 J
Now let's calculate the kinetic energy of the 10 kg rock hitting the car at 15 m/s:
Kinetic energy = (1/2) x 10 kg x (15 m/s)^2
Kinetic energy = 1125 J
Therefore, the 5 kg rock hitting the car at 25 m/s has more kinetic energy than the 10 kg rock hitting the car at 15 m/s.
We can represent this visually using the following equations:
Kinetic energy of 5 kg rock hitting car = (1/2) x 5 kg x (25 m/s)^2 = 1562.5 J
Kinetic energy of 10 kg rock hitting car = (1/2) x 10 kg x (15 m/s)^2 = 1125 J
Σ Kinetic energy of 5 kg rock hitting car > Σ Kinetic energy of 10 kg rock hitting car