Answer:
1/3 x + 40 = 5/7 x
7x +(21)(40) = 15x
21*40 = 8x
x = 105cm3
Step-by-step explanation:
which of the relations given by the following sets of ordered pairs is a function?
a. {(5,2),(4,2),(3,2),(2,2),(1,2)}{(5,2),(4,2),(3,2),(2,2),(1,2)}
b. {(−4,−2),(−1,−1),(3,2),(3,5),(7,10)}{(−4,−2),(−1,−1),(3,2),(3,5),(7,10)}
c. {(−8,−3),(−6,−5),(−4,−2),(−2,−7),(−1,−4)}{(−8,−3),(−6,−5),(−4,−2),(−2,−7),(−1,−4)}
d. {(−6,4),(−3,−1),(0,5),(1,−1),(2,3)}
{(5, 2), (4, 2), (3, 2), (2, 2), (1, 2)}, {(−8, −3), (−6, −5), (−4, −2), (−2, −7), (−1, −4)} and {(−6, 4), (−3, −1), (0, 5), (1, −1), (2, 3)} are the sets of ordered pairs considered as a function.
{(−4, −2), (−1, −1), (3, 2), (3, 5), (7, 10)} is not a function.
In mathematics, ordered pair is a pair of numbers that are written in a specific order. They are generally written in (x, y) form. For example (3, 5) is an ordered pair.
The function can also be represented by a set of ordered pairs. A function Is a set of ordered pairs in which no two different ordered pairs have the same value of x coordinate.
Option (a) : {(5, 2),(4, 2),(3, 2),(2, 2),(1, 2)}
No two ordered pairs have the same value of the x coordinate.
So it is a function.
Option (b) : {(-4, -2),(-1, -1),(3, 2),(3, 5),(7, 10)}
Two ordered pairs have the same value of x coordinate (3, 2) and (3, 5).
So, it can not be considered a function.
Option (c) : {(-8, -3),(-6, -5),(-4, -2),(-2, -7),(-1, -4)}
No two ordered pairs have the same value of the x coordinate.
So it is a function.
Option (d) : {(-6, 4),(-3, -1),(0, 5),(1, -1),(2, 3)}
No two ordered pairs have the same value of the x coordinate.
So it is a function.
Therefore, Options (a), (c), and (d) are the functions.
Option (b) is not a function.
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- Binomial Distribution -
A survey showed that 70% of adults need correction (eyeglasses, contacts, surgery, etc.) for their
eyesight.
If 7adults are randomly selected, find the probability that less than 4 of them need correction for
their eyesight.
Answer: The probability that less than 4 of the 7 adults need correction for their eyesight is approximately 0.1637.
Step-by-step explanation:
This problem can be solved using the binomial distribution, which models the probability of a certain number of successes in a fixed number of independent trials, each with the same probability of success.
Let X be the number of adults among the 7 randomly selected who need correction for their eyesight. Then X follows a binomial distribution with parameters n = 7 (the number of trials) and p = 0.7 (the probability of success in each trial).
We want to obtain the probability that less than 4 of the 7 adults need correction for their eyesight. This can be written as:
P(X < 4) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)
To calculate each of these individual probabilities, we can use the formula for the binomial probability mass function:
P(X = k) = (n choose k) * p^k * (1-p)^(n-k)
where (n choose k) is the binomial coefficient, which represents the number of ways to choose k successes from n trials.
Using this formula, we can calculate each of the probabilities:
P(X = 0) = (7 choose 0) * 0.7^0 * 0.3^7 = 0.0002
P(X = 1) = (7 choose 1) * 0.7^1 * 0.3^6 = 0.0032
P(X = 2) = (7 choose 2) * 0.7^2 * 0.3^5 = 0.0292
P(X = 3) = (7 choose 3) * 0.7^3 * 0.3^4 = 0.1311
Summing these probabilities, we get:
P(X < 4) = 0.0002 + 0.0032 + 0.0292 + 0.1311 = 0.1637
Therefore, the probability that less than 4 of the 7 adults need correction for their eyesight is approximately 0.1637.
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Candida has a ballet recital in one week. She is planning on practicing for 30 minutes each day until the recital. How much time will she practice between now and her ballet recital? A. 2 hours B. 3 hours and 30 minutes C. 4 hours and 30 minutes D. 5 hours
Answer:
B. 3 hours 30 minutes
Step-by-step explanation:
1 week=7 days
30 minutes each day for 7 days
=30 minutes×7 days
=210 minutes
60 minutes makes 1 hour
210/60=3 hours 30 minutes
Candida has 3 hours 30 minutes from now till her ballet recital to practice
B. 3 hours 30 minutes
guys pls help me!!!!!!
Answer:
126°
Step-by-step explanation:
1. We know that 54 degrees and its adjacent are a linear pair, meaning that they add up to 180 degrees. To find the measure of the adjacent angle, we subtract 54 from 180.
\(180 - 54\) \(126\)2. Now, we know that adjacent of 54 is 126. Also, we know that \(l\) ║ \(m\) ║ n, and x and 126 degrees are corresponding angles. Corresponding angles are congruent within angle measures, so x = 126 degrees.
-4+(-2) using the number line of integers
according to the american red cross, 11.4% of all connecticut residents have type b blood. a random sample of 19 connecticut residents is taken. the number of ct residents that have type b blood, of the 19 sampled. what is the expected value of the random variable ?
The expected value of the random variable representing the number of Connecticut residents with type B blood in the sample of 19 is approximately 2.166 residents.
According to the American Red Cross, 11.4% of all Connecticut residents have type B blood. In your question, a random sample of 19 Connecticut residents is taken, and you want to know the expected value of the random variable representing the number of residents with type B blood in the sample.
To find the expected value of this random variable, you can use the following formula:
Expected Value (E[X]) = n * p
where n is the sample size (19 residents) and p is the probability of having type B blood (11.4%, or 0.114 as a decimal).
E[X] = 19 * 0.114 ≈ 2.166
So, the expected value of the random variable representing the number of Connecticut residents with type B blood in the sample of 19 is approximately 2.166 residents.
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Find the solution of the following initial value problem. y ′′ + y = δ(t − 2π) cost; y(0) = 0, y′ (0) = 1
The solution of the given initial value problem is y(t) = sin(t) + H(t-2π)cos(t-2π), where H(t) is the Heaviside step function.
To solve the initial value problem, we start by finding the complementary solution, which satisfies the homogeneous differential equation y'' + y = 0. The complementary solution is given by y_c(t) = A sin(t) + B cos(t), where A and B are constants to be determined.
Next, we find the particular solution for the given non-homogeneous term δ(t-2π)cos(t). Since the forcing term is a Dirac delta function at t = 2π, we can write the particular solution as y_p(t) = K(t-2π)cos(t-2π), where K is a constant to be determined.
Applying the initial conditions y(0) = 0 and y'(0) = 1, we can solve for the constants A, B, and K. Plugging in these initial conditions into the general solution, we find A = 0, B = 1, and K = 1.
Therefore, the solution of the initial value problem is y(t) = sin(t) + H(t-2π)cos(t-2π), where H(t) is the Heaviside step function.
The initial value problem with the given conditions is solved by finding the complementary solution and the particular solution. The solution is y(t) = sin(t) + H(t-2π)cos(t-2π), where H(t) is the Heaviside step function. This solution satisfies the given initial conditions y(0) = 0 and y'(0) = 1.
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Complete the Square
x2 + 10x +
Answer:
( + 10)
Hope this helps you out
-12/7 = 6w solve for w and simplify your answer as much as possible
cliff divers dive headfirst at 8 feet per second from the top of a cliff 87 feet above the pacific ocean. during which time period will the diver's height exceed that of the cliff?
The cliff divers dive headfirst from the top of cliff. 1/2 or 0.5 second is the time period will the diver's height exceed that of the cliff.
Free Fall Object :An object that moves along the vertical axis due to gravitational acceleration is called a free-falling object. The free fall position is given by the following equation of motion:
yₜ = y₀ + v₀t + 1/2(at²)
Where y₀--> the initial height of the object
v₀--> the initial velocity
t --> time
a --> the acceleration due to gravity and is equal to a = g = - 32.2 ft²/sec
We have given that,
Initial velocity of divers , v₀ = 8 feet/sec
Initial Height of top of cliff , s₀ = 87 feet
position function, s(t) = - 16t²+ v₀t +s₀
Plugging all known values in above position function,
s(t) = -16 t² + 8t + 87
The the diver's height exceed that of the cliff means, s(t) > 87
=> -16 t² + 8t + 87 > 87
Subtract 87 from both sides, we get
-16t^2 + 8t > 0 , now we solve this inequality by changing it in a equality,
-16 t² + 8t = 0
=> -8 t( 2t - 1) = 0 => -8t = 0 , 2t -1 = 0
=> either t = 0 or t = 1/2
So the first half second, the person is above the height of the cliff.
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Complete question:
Use the position function s(t)-16t2+ vot +so position, t time) to answer the following: Divers in Acapulco, Mexico, dive headfirst at 8 feet per second from the top of a cliff 87 feet above the Pacific Ocean. During which time period will a diver's height exceed that of the cliff? (vo initial velocity, so initial.
Which set of numbers is an example of an arithmetic sequence
a. 12, 19, 26, 33, 40
b. 1/3, 1/9, 1/15, 1/21, 1/27
c. -6, 18, - 54, 162
d. 1, 1, 2, 3, 5
An organized group of integers with a shared variance among each succeeding word is known as an arithmetic sequence. Hence, the right response is (b). 1/3, 1/9, 1/15, 1/21, 1/27.
Which collection of numbers doesn't fit the definition of an arithmetic sequence?
The following instances don't constitute arithmetic sequences: 1.) 2,4,8,16 is not true since the first with second terms differ by 2, while the third and fourth terms differ by 4, and the fifth and sixth terms differ by 8. There are no shared differences, hence the sequence is not arithmetic.
Is the number sequence 2 2 2 2 2 arithmetic?
The series cannot be an arithmetic sequence, however it may be defined. It does, nevertheless, have a common ratio across succeeding words, namely 1, which results in its geometric growth.
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(1) Using the Black/Scholes Option Pricing Model, calculate the value of the call option given: S=74; X=70;T=6 months; σ2=.50 Rf=10% (2) What is the intrinsic value of the call? (3) What stock price is necessary to break-even? 4 If volatility were to decrease, the value of the call would (5 If the exercise price would increase, the value of the call would ? 6 If the time to maturity were 3-months, the value of the call would ? 77 If the stock price were $62, the value of the call would ? 8 What is the maximum value that a call can take? Why?
(1) Using the Black/Scholes Option Pricing Model, the value of the call option is $7.70.
(2) The intrinsic value of the call is the difference between the stock price and the strike price of the option. Therefore, it is $4.
(3) The stock price required to break-even is the sum of the strike price and the option premium. Therefore, it is $74.
(4) If volatility were to decrease, the value of the call would decrease.
(5) If the exercise price would increase, the value of the call would decrease.
(6) If the time to maturity were 3-months, the value of the call would decrease.
(7) If the stock price were $62, the value of the call would be zero.
(8) The maximum value that a call option can take is unlimited.
In the Black/Scholes option pricing model, the value of a call option can be calculated using the formula:
C = S*N(d1) - X*e^(-rT)*N(d2)
where S is the stock price, X is the exercise price, r is the risk-free rate, T is the time to maturity, and σ2 is the variance of the stock's return.
Using the given values, we can calculate d1 and d2:
d1 = [ln(S/X) + (r + σ2/2)T]/(σ2T^(1/2))
= [ln(74/70) + (0.10 + 0.50/2)*0.5]/(0.50*0.5^(1/2))
= 0.9827
d2 = d1 - σ2T^(1/2) = 0.7327
Using these values, we can calculate the value of the call option:
C = S*N(d1) - X*e^(-rT)*N(d2)
= 74*N(0.9827) - 70*e^(-0.10*0.5)*N(0.7327)
= $7.70
The intrinsic value of the call is the difference between the stock price and the strike price of the option. Therefore, it is $4.
The stock price required to break-even is the sum of the strike price and the option premium. Therefore, it is $74.If volatility were to decrease, the value of the call would decrease. This is because the option's value is directly proportional to the volatility of the stock.
If the exercise price would increase, the value of the call would decrease. This is because the option's value is inversely proportional to the exercise price of the option.
If the time to maturity were 3-months, the value of the call would decrease. This is because the option's value is inversely proportional to the time to maturity of the option.If the stock price were $62, the value of the call would be zero. This is because the intrinsic value of the call is zero when the stock price is less than the strike price.
The maximum value that a call option can take is unlimited. This is because the value of a call option is directly proportional to the stock price. As the stock price increases, the value of the call option also increases.
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find the edge of cube whose volume is 1728cm³
Answer:
12cm long
Step-by-step explanation:
Given data
Volume of cube= 1728cm^3
We know that the expression for the volume is
V=l^3
substitute and solve for l
1728=l^3
cube root both sides
l=∛1728
l=12cm
Hence the edge is 12cm long
Find the volume of the figure below. 5 cm 11 cm 66 cm 82.5 cm 132 cm 165 cm
Answer:
A) 66cm³
Step-by-step explanation:
Using the Pythagorean Theorem, the base of the triangle is 4. The area of a triangle is 1/2 base times height. Then you multiply times 11 to get the volume.
1/2(3)(4)(11)=66
URGENT AND EASY 8TH GRADE MATH
Answer:
k<-62/7
Step-by-step explanation:
I hope it helps.
Answer:
k> 56
Step-by-step explanation:
-35 -k + 6< -85
-29-k < -85
+29 +29
_______________
-k> -56
/-1
k> 56
HELP PLEASE!!! i do not understand
Answer:
a)-3>-7
b)3>-4 The symbol was preserved.
c)-6<8 The symbol was reversed.
Step-by-step explanation:
Hope this helps! :)
Assume the random variable x is normally distributed with mean 50 and standard 7 deviation . Find the indicated probability.
In a normal distribution, the mean represents the center of the distribution and the standard deviation represents the spread of the distribution.
The higher the standard deviation, the more spread out the data is. The probability of a specific outcome occurring is given by the area under the curve of the normal distribution that corresponds to that outcome.
For example, if we wanted to find the probability of x being between 45 and 55, we would find the area under the normal curve between those two values. This can be done using a table of standard normal probabilities or by using a calculator or statistical software.
In general, if we know the mean and standard deviation of a normally distributed random variable, we can use that information to find probabilities for specific outcomes or ranges of outcomes.
you'll need to provide a specific range or value of X. Once you have that, you can use the Z-score formula or a standard normal distribution table to determine the probability.
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Hometown Gym charges a $200 membership fee and $45 per month. Local Gym charges a $50 membership fee and $55 per month. Write an equation to represent the situation. After how many months will the total amount of money paid to both gyms be the same?
Answer:
=> membership fee = $50
=> monthly fee = $55
=> First month = 105$
=> 50 + 55(x)
=> 50 + 55 (15)
=> 50 + 825
=> 875
Workout gym
=> membership fee = $200
=> monthly fee = $45
=> First month = 245$
=> 200 + 45(x)
=> 200 + 45(15)
=> 200 + 675
=> 875
On the first day it was posted online, a music video got 1090 views. The number of views that the video got each day increased by 20% per day. How many total views did the video get over the course of the first 21 days, to the nearest whole number?
Answer:
245278Step-by-step explanation:
The number of views make a GP since increase 20% or 1.2 times per day
1090, 1090*1.2, 1090*1.2², ...The first term is t = 1090 and common ratio is r = 1.2
Find the sum of the first 21 terms
Sₙ = t(rⁿ - 1)/(r - 1) = 1090*(1.2²¹ - 1)/(1.2 - 1) = 245278 (rounded)Answer: 245278 views
Series built : 1090, 1308, 1569.6, 1883.52, 2260.224, 2712.2688,...
As every term increases by 1.2, This is a geometric progression sequence.
\(\sf Geometric \ Sequence: a_1 \ x \ \dfrac{r^n - 1}{r -1}\)
Identify Variable's:
a1 = 1090
r = second term ÷ first term = 1308 ÷ 1090 = 1.2
n = 21
Explanation:
\(\rightarrow \sf 1090 \ x \ \dfrac{(1.2)^{21} - 1}{(1.2) -1}\)
\(\rightarrow \sf 245277.9035\)
\(\rightarrow \sf 245278 \ \ \ \ \ (rounded \ to \ nearest \ integer)\)
can somebody find the volume of the cone on #2?
thank you!!
Answer:
\( 4,220.16 \: {units}^{3} \)
Step-by-step explanation:
Diameter of cone = 24 units
Radius of cone (r) = 24/2 = 12 units
Height of cone (h) = 28 units
\(V_{cone} = \frac{1}{3} \pi {r}^{2}h \\ \\ = \frac{1}{ 3} \times 3.14 \times {(12)}^{2} \times 28 \\ \\ = \frac{1}{3} \times 3.14 \times 144 \times 28 \\ \\ = 3.14 \times 1,344 \\ \\ = 4,220.16\: {units}^{3} \)
Alex plays rugby and can burn approximately 650 calories in a 1.25-hour game. Danielle enjoys
kickboxing and can burn approximately 420 calories in a 45-minute class. Who burns calories at
a higher rate?
Answer:
Danielle burns calories at a higher rate
Step-by-step explanation:
Alex: 650/75=8 2/3 calories per minute
Danielle: 420/45=9 1/3 calories per minute
pls help me on this!
Answer:
5 2/3
Step-by-step explanation:
So because it is a mixed number that means you want to have a whole plus a fraction. You keep the 5 as the whole and because 2/3=.666666. You add them together making 5 2/3.
convert from standard form to slope intercept form
Answer:
its always C trush me on this one
Step-by-step explanation:
Answer:
Its y=-x-3
Step-by-step explanation:
x+y=-3
You would subtract the x to make it a y equals statement
y=-x-3
the -3 stays the same all thats different is the x which you will subtract over since its added to the y.
Problem 1 Find the acceptance angles of the right -angle prism (a) and corner reflector (b) made from the glass (n=1.5). Acceptance angle (2θ
out
) is the angle subtending the cone of the light rays that will be totally internally reflected by the prism. b
The acceptance angle of a right-angle prism made from glass (n=1.5) is approximately 41.8 degrees. The acceptance angle of a corner reflector made from glass (n=1.5) is approximately 90 degrees.
(a) For a right-angle prism, the acceptance angle (2θ_out) is the angle at which the incident light ray inside the prism reaches the critical angle and undergoes total internal reflection. The critical angle can be determined using Snell's law, which states that sin(θ_c) = 1/n, where n is the refractive index of the medium (in this case, n=1.5 for glass). Solving for θ_c, we find θ_c = sin^(-1)(1/n). Since the incident angle inside the prism is equal to the critical angle, the acceptance angle is 2θ_c. Substituting n=1.5, we find 2θ_out ≈ 2 * sin^(-1)(1/1.5) ≈ 41.8 degrees.
(b) A corner reflector is formed by three mutually perpendicular plane mirrors, such as those in a prism. In a corner reflector made from glass (n=1.5), each mirror surface will have an acceptance angle equal to the critical angle. Using the same formula as in (a), we find θ_c = sin^(-1)(1/1.5). Since each mirror is perpendicular to the others, the total acceptance angle of the corner reflector is the sum of the acceptance angles of the individual mirrors, which results in 2θ_out ≈ 2 * sin^(-1)(1/1.5) ≈ 90 degrees.
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A sinking fund is established to discharge a debt of $70,000 in 10 years. if deposits are made at the end of each 6-month period and interest is paid at the rate of 9%, compounded semiannually, what is the amount of each deposit? (round your answer to the nearest cent.)
The amount of each deposit is $210000
What is compound interest?Compound interest is when you reinvest your income. Compound interest distinctively means "interest on interest" and is the reason so many investors are so successful.
The computation of the each deposit is shown below:
Given that
Future value be $70,000
Time period = 10 × 2 = 20
And, the rate = 9% ÷ 2 = 4.5%
Now the formula is as follows
= (Future value × rate of interest) ÷ (1 + rate of interest)^time period - 1
= ($70,000 × 4.5) ÷ (1 + 0.025)²⁰⁻¹
= $315,000 ÷ 1.5
= $210000
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Please simplify the following expression while performing the given operation.
(-3+1)+(-4-i)
Answer:
To simplify the expression (-3+1)+(-4-i), we can perform the addition operation within the parentheses first:
(-3+1)+(-4-i) = -2 + (-4-i)
Next, we can simplify the addition of -2 and -4 by adding their numerical values:
-2 + (-4-i) = -6 - i
Therefore, (-3+1)+(-4-i) simplifies to -6-i.
Step-by-step explanation:
Can I get help with this
Answer:
Step-by-step explanation:
3(a^2 + a - 6)
3(a + 3)(a - 2)
answer is D
Can someone please help me with this question?
A semicircle has radius 5.6cm. Work out the perimeter of the semicircle.
Answer:
28.79 cm.
Step-by-step explanation:
The perimeter of a semicircle is equal to the sum of the diameter (which is twice the radius) and half of the circumference of the circle.
The diameter of the semicircle is 2 × 5.6cm = 11.2cm.
The circumference of a full circle with radius 5.6cm is 2π × 5.6cm = 11.2π cm.
Therefore, the circumference of the semicircle is 1/2 of the circumference of the full circle, which is 1/2 × 11.2π cm = 5.6π cm.
The perimeter of the semicircle is the sum of the diameter and the circumference, which is:
11.2cm + 5.6π cm ≈ 28.79cm (rounded to two decimal places)
Therefore, the perimeter of the semicircle is approximately 28.79 cm.
Answer:
pi ( 5.6 ) + 11.2 or approximately 28.79291 cm
Step-by-step explanation:
The outside of the semicircle or the perimeter is 1/2 of the circumference and the length that closes the circle is the diameter.
Perimeter = 1/2 C + d
= 1/2 *pi*d + d
The diameter is 2 times the radius.
= 1/2 ( pi) * (2r) + 2r
= pi r + 2 r
= pi ( 5.6 ) + 11.2
Approximating pi, we get approximately 28.79291
Solve. x/4 + ½ = 1/8
x = ____ (Simplify your answer.)
Answer:
\( \frac{x}{4} + \frac{1}{2} = \frac{1}{8} \)
\( \frac{x}{4} = - \frac{3}{8} \)
\(x = - \frac{3}{2} = - 1 \frac{1}{2} \)
The solution to the equation x/4 + 1/2 = 1/8 is x = -3/2.
Consider the equation, we have only one x term, so taking all the terms without x to the other side and terms with x on one side.
x/4 + 1/2 = 1/8
Take the 1/2 term on the other side,
x/4=1/8 - 1/2
Taking the LCM on the Right side,
x/4 = (1-4) / 8
x/4 = -3/8
Now, we have x/4 so what we can do is, shift the 4 to the other side too, we get,
x = ( -3/8) * 4
x = -3/2
The solution to the equation x/4 + 1/2 = 1/8 is x = -3/2.
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Petra’s electricity supply company charges her a fixed quarterly sum plus a rate per unit for electricity used. In the most expensive quarter last year (January to March), she used 2 000 units and her bill was $250. In the least expensive quarter (July to September), she used 600 units and her bill was $138. She is now adding extra insulation to her home which is expected to reduce her overall electricity consumption by 25%. What can she expect her January to March bill to be next year (if there are no increases in overall tariffs)? *
Answer:
$210
Step-by-step explanation:
(January - March) charge last year :
Unit consumed = 2000
Bill = $250
(July - September) charge last year:
Unit consumed = 600 units
Bill = $138
Billing :
Fixed charge + rate per unit ;
Let fixed charge = c ; rate per unit = m
Billing can be represented by the equation :
mx + c = y
x = unit consumed ; y = total charge
Expensive quarter:
2000x + c = 250 - - - (1)
Least expensive quarter:
600x + c = 138 - - - (2)
From (2)
c = 138 - 600x ; plug into (1)
2000x + 138 - 600x = 250
1400x = 250 - 138
1400x = 112
x = 0.08
0.08 = x = rate per unit
From ; c = 138 - 600x
c = 138 - 600(0.08)
c = 90
Fixed charge = 90
Billing equation :
y = 0.08x + 90
If insulation will reduce unit consumption by 25%
Then, consumption in most expensive quarter will be :
(100 - 25)% * 2000
0.75 * 2000 = 1500 units
Charge will be :
(0.08*1500) + 90
= $210