The measure of <B is 61 degree.
length of arc CD = 20.859 unit and length of are BD = 22.4118 unit.
First, using Angle sum property in triangle DCB
<D + <C + <B = 180
49 + 70 + <B= 180
<B = 180 - 119
<B = 61 degree
Now, using sine law
CB / sin 49 = BD / sin 70
18 / 0.75470958022 = BD / 0.93969262078
BD = 22.4118
and, 18 / 0.75470958022 = CD / 0.87461970713
CD = 20.859
Learn more about Sine law here:
https://brainly.com/question/13098194
#SPJ1
What is the slope of line p
you toss a fair coin 9 times. find the probability of no more than 8 heads given that at least one toss resulted in heads.
The probability of no more than 8 heads given that at least one toss resulted in heads will be 511/512.
What is probability ?
Mathematical explanations of the likelihood that an event will occur or that a statement is true are referred to as probabilities. A number between 0 and 1 represents the likelihood of an event, with 0 generally denoting impossibility and 1 denoting certainty.
A coin has two possibility, either head or tail.
So, there will be 2 possible outcomes when a coin is tossed.
hence, Total no. of outcomes (T) = 2^9. = 512
Now, Probability of getting one tail = 1/2^9 = 1/512
and, Probability of getting at most 8 heads
= 1 - Probability of getting one tail
= 1 - 1/512
= 511/512.
Learn more about Probability from the link given below:
https://brainly.com/question/13604758
#SPJ4
Consider the damped mass-spring system for mass of 0.7 kg, spring constant 8.7 N/m, damping 1.54 kg/s and an oscillating force 3.3 cos(wt) Newtons. That is, 0.72" + 1.54x' +8.7% = 3.3 cos(wt). What positive angular frequency w leads to maximum practical resonance? = w= 3.16 help (numbers) the steady state solution when the What is the maximum displacement of the mass we are at practical resonance: = CW) =
Plugging in the value of w = 3.156 rad/s, we can calculate the maximum Displacement.
To find the positive angular frequency w that leads to maximum practical resonance, we can solve the given equation for steady-state response by setting the input force equal to the damping force.
The given equation represents a damped mass-spring system with an oscillating force. The equation of motion for this system can be written as:0.72x'' + 1.54x' + 8.7x = 3.3cos(wt)
To determine the angular frequency w that leads to maximum practical resonance, we need to find the value of w that results in the maximum amplitude of the steady-state response.
The steady-state solution for this equation can be expressed as:
x(t) = X*cos(wt - φ)
where X is the amplitude and φ is the phase angle.
To find the maximum displacement (maximum amplitude), we can take the derivative of the steady-state solution with respect to time and set it equal to zero:
dx(t)/dt = -Xwsin(wt - φ) = 0
This condition implies that sin(wt - φ) = 0, which means wt - φ must be an integer multiple of π.
Since we are interested in finding the maximum practical resonance, we want the amplitude to be as large as possible. This occurs when the angular frequency w is equal to the natural frequency of the system.
The natural frequency of the system can be calculated using the formula:
ωn = sqrt(k/m)where k is the spring constant and m is the mass.
Given that the mass is 0.7 kg and the spring constant is 8.7 N/m, we can calculate the natural frequency:
ωn = sqrt(8.7 / 0.7) ≈ 3.156 rad/s
Therefore, the positive angular frequency w that leads to maximum practical resonance is approximately 3.156 rad/s.
To calculate the maximum displacement (maximum amplitude) of the mass at practical resonance, we need to find the amplitude X. Given the steady-state equation: x(t) = X*cos(wt - φ)
We know that at practical resonance, the input force is equal to the damping force:3.3cos(wt) = 1.54x' + 8.7x
By solving this equation for the amplitude X, we can find the maximum displacement: X = (3.3 / sqrt((8.7 - w^2)^2 + (1.54 * w)^2))
Plugging in the value of w = 3.156 rad/s, we can calculate the maximum displacement.
To know more about Displacement.
https://brainly.com/question/1581502
#SPJ11
The maximum displacement is:x_max = 0.695 cos(-0.298) = 0.646 m (approx)
The steady-state solution for the given damped mass-spring system is of the form:
x(t) = A cos(wt - phi)
where A is the amplitude of oscillation, w is the angular frequency, and phi is the phase angle.
To find the angular frequency that leads to maximum practical resonance, we need to find the value of w that makes the amplitude A as large as possible. The amplitude A is given by:
A = F0 / sqrt((k - mw^2)^2 + (cw)^2)
where F0 is the amplitude of the oscillating force, k is the spring constant, m is the mass, and c is the damping coefficient.
To maximize A, we need to minimize the denominator of the above expression. We can write the denominator as:
(k - mw^2)^2 + (cw)^2 = k^2 - 2kmw^2 + m^2w^4 + c^2w^2
Taking the derivative of the above expression with respect to w and setting it to zero, we get:
-4kmw + 2m^2w^3 + 2cw = 0
Simplifying and solving for w, we get:
w = sqrt(k/m) / sqrt(2) = sqrt(8.7/0.7) / sqrt(2) = 3.16 rad/s (approx)
This is the value of w that leads to maximum practical resonance.
To find the steady-state solution at practical resonance, we can substitute w = 3.16 rad/s into the equation of motion:
0.7x'' + 1.54x' + 8.7x = 3.3 cos(3.16t)
The steady-state solution is of the form:
x(t) = A cos(3.16t - phi)
where A and phi can be determined by matching coefficients with the right-hand side of the above equation. We can write:
x(t) = Acos(3.16t - phi) = Re[Ae^(i(3.16t - phi))]
where Re denotes the real part of a complex number. The amplitude A can be found from:
A = F0 / sqrt((k - mw^2)^2 + (cw)^2) = 3.3 / sqrt((8.7 - 0.7(3.16)^2)^2 + (1.54(3.16))^2) = 0.695
The maximum displacement occurs when cos(3.16t - phi) = 1, which happens at t = 0. Therefore, the maximum displacement is:
x_max = A cos(-phi) = 0.695 cos(-phi)
The phase angle phi can be found from:
tan(phi) = cw / (k - mw^2) = 1.54 / (8.7 - 0.7(3.16)^2) = 0.308
phi = atan(0.308) = 0.298 rad
Know more about maximum displacement here:
https://brainly.com/question/14150511
#SPJ11
The average score of students in the first group is 39, the second group is 32, and the third group is 43. If the numbers of students in the three groups are 24, 26, and 27, respectively, find the average score of all students.
The average score of all students, calculated by taking a weighted average based on the number of students in each group, is 38. The overall performance is slightly below the group averages.
The average score of students in the first, second, and third groups are 39, 32, and 43, respectively. There are 24 students in the first group, 26 students in the second group, and 27 students in the third group.
To find the average score of all students, we need to take a weighted average of the scores in each group, with the number of students in each group as the weights.
Here's how to do it: First, we calculate the total number of students:24 + 26 + 27 = 77. Then, we calculate the total score across all students: 39*24 + 32*26 + 43*27 = 936 + 832 + 1161 = 2929
Finally, we divide the total score by the total number of students to get the average score:2929/77 = 38. The average score of all students is 38.
This means that the overall performance of all the students is slightly below the average of the scores in each group.
For more questions on average score
https://brainly.com/question/13832161
#SPJ8
If x < y, then all of the following are true except _____. < 2 x < 2 y - x < - y x + 2 < y + 2.
If x < y, then all of the following are true except - x < -y.
What is inequality?
A declaration of an order relationship between two numbers or algebraic expressions, such as greater than, greater than or equal to, less than, or less than or equal to.
A statement that demonstrates the connection between two (or more) phrases containing one of the following five signs:,, >,, is known as an inequality. An inequality can be true or untrue, just like an equation. The statement "34 - 12 > 5 + 2" is accurate. A false statement is made when 1 + 3 6 - 2.
The value remains the same after addition, multiplication, and division.
However, if you reverse the sign, the inequality direction in this instance will be >; otherwise, that is not true.
For example,
2 < 3
-2 < -3 is not true.
Because -2 is greater than -3.
Learn more about Inequalities click here:
https://brainly.com/question/24372553
#SPJ4
What’s the slope to this graph?
Answer:
6/3
Step-by-step explanation:
I think bhjukjkfiffo
Answer:
-5/3
Step-by-step explanation:
rise/run you go down 5 and over 3
The electric potential of a point charge Q located at the origin of the Cartesian coordinate system is V=
4πε
0
(x
2
+y
2
+z
2
)
1/2
Q
. Find the corresponding electric field E. (a) E=
4πε
0
Q
(x
2
+y
2
+z
2
)
1/2
x
x
^
+y
y
^
+z
z
^
(b) E=
4πε
0
Q
(x
2
+y
2
+z
2
)
2
x
x
^
+y
y
^
+z
z
^
(c) E=
4πε
0
Q
(x
2
+y
2
+z
2
)
x
x
^
+y
y
^
+z
z
^
(d) E=
4πε
0
Q
(x
2
+y
2
+z
2
)
3/2
x
x
^
+y
y
^
+z
z
^
The correct option that represents the electric field is:
Option D: E = 4πε₀Q(x² + y² + z²)^(3/2)x^ + y^ + z^
How to find the Electric Field using partial Derivatives?The electric field is given by the formula:
E = -∇V
where:
∇ is the del operator, which in Cartesian coordinates is represented as:
∇ = (∂/∂x)x^ + (∂/∂y)y^ + (∂/∂z)z^
Taking the negative gradient of V gives us:
E = -∇V = -[(∂V/∂x)x^ + (∂V/∂y)y^ + (∂V/∂z)z^]
First, let's calculate the partial derivatives of V with respect to x, y, and z:
(∂V/∂x) = (∂/∂x)[4πε₀(Q/√(x² + y² + z²))]
= -4πε₀(Qx/√(x² + y² + z²)³)
(∂V/∂y) = (∂/∂y) [4πε₀(Q/√(x² + y² + z²))]
= -4πε₀(Qy/√(x² + y² + z²)³)
(∂V/∂z) = (∂/∂z) [4πε₀(Q/√(x² + y² + z²))]
= -4πε₀(Qz/√(x² + y² + z²)³)
Now, substituting these derivatives into the expression for E:
E = -[(-4πε₀(Qx/√(x² + y² + z²)³))x^ + (-4πε₀(Qy/√(x² + y² + z²)³))y^ + (-4πε₀(Qz/√(x² + y² + z²)³))z^]
Simplifying, we have:
E = 4πε₀Q(x/√(x² + y² + z²)³)x^ + 4πε₀Q(y/√(x² + y² + z²)³)y^ + 4πε₀Q(z/√(x² + y² + z²)³) z^
Therefore, the correct option is:
(d) E = 4πε₀Q(x² + y² + z²)^(3/2)x^ + y^ + z^
Read more about Electric field at: https://brainly.com/question/32891246
#SPJ1
Jeff had $20. He spent 18
1
8
of his money on lunch and 25
2
5
of his money at the movies.
How much money does Jeff have left?
$5.50
Jeff does not have any money left.
How to determineJeff originally had $20. He spent 18 1/8 of his money on lunch and 25 2/5 of his money at the movies. To find out how much money Jeff has left, we need to subtract the amount he spent from the original amount.
First, we need to convert the fractions to decimals so we can easily subtract them from the original amount. 18 1/8 = 18.125 25 2/5 = 25.4
Now we can subtract these amounts from the original amount: $20 - $18.125 - $25.4 = -$23.525
Since Jeff cannot have a negative amount of money, this means that he does not have enough money to cover the cost of both lunch and the movies. Therefore, Jeff does not have any money left.
Learn more about remaining money at https://brainly.com/question/17925574.
#SPJ11
Consider a sample space with 7 elements. Let A be an event with 5 elements and B be an event with 4 elements. Let's assume that there are 2 repeated elements between both events.P(A y B) =A) 4/7B) 2/7C) 5/7D) 9
Option D (9) is not a probability and is not a possible answer choice for a probability question.
To find the probability of the intersection of events A and B (denoted as P(A ∩ B)), we need to know how many elements are in both A and B. Since there are 2 repeated elements between the events, this means that there are a total of 7 - 2 = 5 distinct elements between them.
Therefore, P(A ∩ B) = 5/7.
Note that none of the answer choices provided match this result exactly. Option A is the closest with a probability of 4/7, but this is the probability of A alone, not the intersection of A and B. Option B (2/7) is the probability of B alone and option C (5/7) is the probability of either A or B occurring, not the intersection.
Know more about probability here:
https://brainly.com/question/30034780
#SPJ11
I need help on this too
The marginal profit of a certain commodity is P(q)=100−2q when q units are produced. When 10 units are produced, the profit is $700 . Find the profit function P(q)
Given information: The marginal profit of a certain commodity is
P(q)=100−2q
when q units are produced. When 10 units are produced, the profit is $700.
To find: Profit function P(q)Formula used:
Profit = Total Revenue - Total Cost
Total Revenue = Selling Price x Quantity.
Total Cost = Fixed Cost + Variable Cost
x Quantity Profit function can be defined as the difference between total revenue and total cost. Since we have the marginal profit function
P(q) = 100 - 2q,
we can find the total profit function by integrating this marginal profit function.
So,
∫P(q)dq = ∫(100 - 2q)dq=100q - q²/2 + C
Where C is the constant of integration.
To find the constant of integration, we can use the given information that when 10 units are produced, the profit is $700. Therefore, using the profit formula,
Profit = Total Revenue - Total Cost700 = SP - TC
We are not given the selling price and fixed cost, but we can find the variable cost using the marginal profit function.
When q = 10, P(q) = 100 - 2(10) = 80Therefore, the variable cost of producing
10 units = 700/80 = $8.75
Now, we can use the variable cost and marginal profit function to find the fixed cost.
Fixed Cost + Variable Cost
x 10 = 1000-8.75 x 10 = 1000 - 87.5 = $912.5
Now we can substitute the value of C in the total profit function obtained above.
100q - q²/2 + 912.5 = P(q)
the profit function
P(q) is given by:
P(q) = 100q - q²/2 + 912.5
Thus, the required answer is more than 100 words.
To know more about integration visit:
https://brainly.com/question/31744185
#SPJ11
24 boys started a cycle racc and 18 of them
ended the race. What percentage of boys
ended the race?
ation owned
Your collection of baseball cards cost you $175 in 2004. In 2017 the value of the collection had increased by approximately 7.5% each yearWhat is the value of the cards in 2017?
Graph the function. F(x) = 2x^2-5
Answer:
see attached
Step-by-step explanation:
You want a graph of the function F(x) = 2x² -5.
GraphA graphing calculator can help a lot when you want the graph of a function. This one is an x² function with a vertical translation of -5 and a vertical stretch by a factor of 2.
It is often useful to consider points ±1 or ±2 either side of the vertex, and the vertex itself.
The graph is attached.
A forest fire which is initially 60 acres grows by 20% each day. firefighters battling the blaze can put out 15 acres of fire per day. what is the recursive rule for the number of an acres at the beginning of the nth day. how many acres are burning at the 8th day?
The recursive rule for the number of acres at the beginning of the nth day in a forest fire that grows by 20% each day and is battled by firefighters who can put out 15 acres per day is given by: A(n) = 1.2 * A(n-1) - 15, where A(n) represents the number of acres at the beginning of the nth day. Using this rule, we can calculate that there are 89.6 acres burning at the beginning of the 8th day.
Explanation: To determine the recursive rule for the number of acres at the beginning of the nth day, we need to consider the given information. The forest fire initially covers 60 acres and grows by 20% each day. This means that the number of acres at the beginning of the next day (n+1) is 1.2 times the number of acres at the beginning of the current day (n). However, the firefighters are able to put out 15 acres of fire per day.
Therefore, to calculate A(n), we start with the initial number of acres, which is 60, and apply the recursive rule. A(n) = 1.2 * A(n-1) - 15. This formula takes into account the growth of the fire by 20% and the reduction of 15 acres due to the firefighters' efforts. By substituting the values, we can calculate the number of acres at the beginning of each day.
To find the number of acres burning at the 8th day, we substitute n = 8 into the recursive rule. A(8) = 1.2 * A(7) - 15. We need to determine A(7) first by substituting n = 7, and so on, until we reach the initial value A(1) = 60. Once we have calculated A(8), we can determine that there are 89.6 acres burning at the beginning of the 8th day
Learn more about recursive rule here : brainly.com/question/2059043
#SPJ11
In the coordinate plane, the point A (-2,0) is translated to the point A prime (-6,-3) . Under the same translation B(2, 4) the points and C (1,-4) are translated to B prime and C prime , respectively. What are the coordinates of B prime and C prime ?
Under the given translation, the point B(2, 4) is translated to B'(-2, 1), and the point C(1, -4) is translated to C'(-3, -7).
To find the coordinates of B' and C' after the translation, we need to determine the change in x and y coordinates for each point.
For point B, the x-coordinate changes by -2 and the y-coordinate changes by -3. Therefore, the coordinates of B' are (-2 + 2, 4 + (-3)), which simplifies to (-2, 1).
Similarly, for point C, the x-coordinate changes by -2 and the y-coordinate changes by -3. Thus, the coordinates of C' are (1 + (-2), -4 + (-3)), which simplifies to (-3, -7).
In conclusion, the coordinates of B' are (-2, 1) and the coordinates of C' are (-3, -7) under the given translation.
Learn more about translation here
https://brainly.com/question/30613034
#SPJ11
compute a ⨯ b, where a = i − 9j k, b = 8i j k.
Computation of the cross product (a ⨯ b) of the given vectors a = i - 9j + k and b = 8i + j + k, gives -10i + 7j + 73k.
To compute the cross product (a ⨯ b) of the given vectors a = i - 9j + k and b = 8i + j + k, follow these steps:
1. Write the cross product formula:
a ⨯ b = (\(a_{2}b_{3} -a_{3} b_{2}\))i - (\(a_{1} b_{3}- a_{3} b_{1}\))j + (\(a_{1} b_{2}- a_{2} b_{1}\))k
2. Plug in the values from the given vectors:
a ⨯ b = ((-9)(1) - (1)(1))i - ((1)(1) - (1)(8))j + ((1)(1) - (-9)(8))k
3. Simplify:
a ⨯ b = (-9 - 1)i - (1 - 8)j + (1 + 72)k
a ⨯ b = -10i + 7j + 73k
So, the cross product of the given vectors is -10i + 7j + 73k.
Learn more about cross product here:
https://brainly.com/question/29164170
#SPJ11
How many solution does the system of linear equations represented in the graph below have?.
Answer:
No solution
Step-by-step explanation:
The given lines on the graph are parallel . So they will never intersect each other. Therefore they have no solution.
QUESTION OF THE DAY: Judy is recreating a small version of the Statue of Liberty out of clay. The scale for the statue is 3 inches to 100 feet. If the actual height of the statue is 305 feet, what would the height of the model be in inches?
Answer:
184in
Step-by-step explanation:
Since the scale for the statue is 3 inches to 100 feet, we can say 3:100 as a ratio.
To find approximately 305 feet you must divide 305 by 100.
100 can go into 300 evenly 3 times. Since the ratio is 3:100 you should multiply how many times the 100ft fit into the 300ft and the 3in (3 x 3) which is about 9in.
One way we can do this is to divide the hight of the Statue by the model height:
305ft 20in = 15.25ft 1in or 184in (12in per foot).
And so for every inch of the model, it represents 15.25 feet.
For 305 it would be
how do I do this ??
Answer:
If I'm not mistaking, they want you to find the number in the middle that's between X and Z.
That number would be 3.
Hope this helps a bit! :)
Answer:
y would be at 3
Step-by-step explanation:
How much space is in between x and z?: 8 - -2 = 8 + 2 = 10The midpoint of 10 is 5: -2 + 5 = 3I hope this helps!
Explain how to get the variable alone in the following equation. C = 11 = 5
Step-by-step explanation:
First you subtract five on both sides. Now we're left with C=6
1 ptSome plants rely on hummingbirds for pollination. If a deadly disease infected the hummingbird population, what would MOST likely happen to the plants? They would die within hours.They would become endangered.They would need to migrate.They would grow at a slower rate.
If a deadly disease infected the hummingbird population, what would most likely happen to the plants option (b) They would become endangered
If a deadly disease infected the hummingbird population, it would most likely lead to a decrease in the pollination of plants that rely on hummingbirds for pollination. Without the hummingbirds to transfer pollen between flowers, these plants would have a reduced rate of successful pollination, which would result in a decrease in their ability to reproduce.
However, it is unlikely that the plants would die within hours or become endangered immediately, nor would they need to migrate. The effect of the loss of hummingbird pollinators on the plants would depend on the specific plant species, their pollination requirements, and the availability of alternative pollinators. Some plants may be more adaptable to using alternative pollinators, while others may suffer more severe consequences. It is also possible that the loss of hummingbirds could lead to a decline in the populations of other animals that depend on the plants, creating a ripple effect in the ecosystem.
Therefore, the correct option is (d) They would become endangered
Learn more about hummingbird here
brainly.com/question/17536527
#SPJ4
evaluate g(10)=-3x+1
Answer:
-29
Step-by-step explanation:
-3(10)+1
-30+1
-29
3. A sari is sold for $60 thereby making a profit of 20% on the cost
price. What was the cost price?
Answer:
The cost price was $48
Step-by-step explanation:
60-20%=48
hope it helps :)
Answer:
50
Step-by-step explanation:
60-x*100=20
6000-100x=20x
6000=20x+100x
6000= 120x
x= 6000/120
x= 50
Find the general solution of the given system. x' = (-1 -6 6 11)x x(t) =
The general solution of the system is given by x(t) = c_1 * v_1 * e^(λ_1 * t) + c_2 * v_2 * e^(λ_2 * t), where c_1 and c_2 are constants. Thus, the general solution of the given system is x(t) = c_1 * (6 1) * e^(12.32 * t) + c_2 * (-2 3) * e^(-2.32 * t).
The given system can be represented as x' = Ax, where A is the coefficient matrix (-1 -6 6 11). To find the eigenvalues and eigenvectors, we solve the characteristic equation det(A - λI) = 0, where I is the identity matrix.
Setting up the characteristic equation, we have:
det((-1-λ) -6; 6 (11-λ)) = 0,
(λ+1)(λ-11) - 36 = 0,
λ^2 - 10λ - 47 = 0.
Solving this quadratic equation, we find the eigenvalues λ_1 ≈ 12.32 and λ_2 ≈ -2.32.
Next, we find the corresponding eigenvectors by solving (A - λI)v = 0 for each eigenvalue. For λ_1 ≈ 12.32, we get the eigenvector v_1 = (6 1). For λ_2 ≈ -2.32, we get the eigenvector v_2 = (-2 3).
The general solution of the system is given by x(t) = c_1 * v_1 * e^(λ_1 * t) + c_2 * v_2 * e^(λ_2 * t), where c_1 and c_2 are constants. Thus, the general solution of the given system is x(t) = c_1 * (6 1) * e^(12.32 * t) + c_2 * (-2 3) * e^(-2.32 * t).
To learn more about eigenvalues click here, brainly.com/question/29861415
#SPJ11
The equation c = 10.50p represents the proportional relationship between the total cost (c) and the number of pounds (p) of shrimp at a grocery store.
Which description is true, based on the equation of the proportional relationship?
For $0.50, you can buy 1 pound of shrimp.
For $1, you can buy 10.50 pounds of shrimp.
For $10.50, you can buy 10.50 pounds of shrimp.
For $10.50, you can buy 1 pound of shrimp.
Answer:
For $10.50, you can buy 1 pound of shrimp
Step-by-step explanation:
We know that "c" is the total cost and "p" is the number of pounds of shrimp. The number 10.50 is considered to rate for every pound of shrimp because, if we replace "p" with 1 pound, we will get the answer of $10.50. Thus, it costs $10.50 for every pound of shrimp.
I am a multiple of 12 . i am between 40 and 50 . who could i be
Answer:
48
Step-by-step explanation:
if its not right sorry
2. Ravi purchased an old house for Rs. 76.5000 and
spent Rs. 115000 on its. Then he sold it at a
gain of 5%. How many
much did he get.
Answer:
Rs. 924000.
Step-by-step explanation:
Cost of house = 765000
Additional money spent on it = 115000
Total cost incurred by Ravi = 765000 + 115000 = 880000
Gain = 5% of total cost
gain in Rs = 5/100 * 880000 = Rs. 44000
Total selling price of house = total cost incurred + profit = 880000+ 44000
Total selling price of house = Rs. 924000
Thus, Ravi got Rs. 924000.
PLEASE HELP I REALLY NEED HELP!
Answer:
It should be C. AAS
Step-by-step explanation:
There are symbols on the triangle indicating a shared right triangle, congruent angles, and a shared congruent side.
Hope this helps :)
Answer:
Yes, AAS
Step-by-step explanation:
After 2.5 years your investment account has earned $450 in interest. If the interest rate is 7.5% what was the principle on your account?
Answer: $2400
Step-by-step explanation:
Given
Interest earned is $450
The rate of interest is R=7.5%
Time period T=2.5 years
Simple Interest is given by
\(S.I.=\dfrac{P\times R\timesT}{100}\quad [\text{P=Principal}]\)
Substitute values
\(450=\dfrac{P\times 7.5\times2.5}{100}\\\\P=\dfrac{450\times 100}{7.5\times 2.5}=\$2400\)