Answer:
the first one
Step-by-step explanation:
I just took it on edge.
Answer:
It is B just took the unit quiz
Step-by-step explanation:
What’s the correct answer for this?
Answer:
D
Step-by-step explanation:
Length × Width = Area
So we'll substitute the Area of the circle having formula, πr²
I will mark brainly-ist to who ever helps me
Find the value of the logarithm.
log 110
Round your answer to the nearest thousandth.
Answer:
4.700
Step-by-step explanation:
Find the number in the thousandth place 0 and look one place to the right for the rounding digit 4. Round up if this number is greater than or equal to 5 and round down if it is less than 5.
brainliesssss plssssssssssssss
What are the solutions to the quadratic equation 2x^2 + 10x - 48 = 0?
A. x= -4 and x = 6
B. X= -8 and x = 2
c. x= -6 and x = 8
D. X = -8 and x = 3
What is the equation of the line perpendicular to y = 2/3 x +1 that passes through the point (12, – 6)?
Answer:
y= -3/2x+12
Step-by-step explanation:
the slope of perpendicular lines multiplied together would be -1, so the slope of the perpendicular line is -3/2. y=-3/2x+b, so -6=-18+b, so b= 12. the equation of the line is y=-3/2x+12.
Please help. I’ll mark you as brainliest if correct!
These are 2 math problems .
Answer:
-4 503/12 ≈ 41.91667Step-by-step explanation:
To find the average rate of change, find the change in function value, and divide that by the length of the interval.
1. ((g(1) -g(-1))/(1 -(-1)) = ((-4·1³ +4) -(-4(-1)³ +4)/(2) = (-8)/2 = -4
The average rate of change of g(x) on [-1, 1] is -4.
__
2. ((g(3) -g(-2))/(3 -(-2)) = ((6·3³ +3/3²) -(6·(-2)³ +3/(-2)²))/5
= (6·27 +1/3 -6·(-8) -3/4)/5 = (2515/12)/5
= 503/12 = 41 11/12
The average rate of change of g(x) on [-2, 3] is 41 11/12.
A rectangular piece of paper has a width that is 3 inches less than its length. It is cut in half along a diagonal to create two congruent right triangles with areas of 44 square inches. Which statements are true? Check all that apply.
The area of the rectangle is 88 square inches.
The equation x(x – 3) = 44 can be used to solve for the dimensions of the triangle.
The equation x2 – 3x – 88 = 0 can be used to solve for the length of the rectangle.
The triangle has a base of 11 inches and a height of 8 inches.
The rectangle has a width of 4 inches.
Answer:
⬇⬇⬇⬇⬇⬇
⬇⬇⬇⬇⬇⬇
Step-by-step explanation:
1, 3, 4
proof below
(1) The area of the rectangle is 88 square inches
(3) The equation x² – 3x – 88 = 0 can be used to solve for the length of the rectangle.
(4) The triangle has a base of 11 inches and a height of 8 inches.
Area of the rectangle
Area of a rectangle is the sum of the area of two equal right triangle.
Area of rectangle = 2(area of right triangle)
Area of rectangle = 2(44 sq inches) = 88 sq inches
Total area of the triangle with respect to length and width of the rectangleLet the length = x
then the width becomes, x - 3
Area = x(x - 3) = 88
x² - 3x = 88
x² - 3x - 88 = 0
x = 11
width = 11 - 3 = 8
Thus, the statements that are true include;
The area of the rectangle is 88 square inchesThe equation x² – 3x – 88 = 0 can be used to solve for the length of the rectangle.The triangle has a base of 11 inches and a height of 8 inches.Learn more about area of rectangle here: https://brainly.com/question/25292087
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What’s the correct answer for this question?
Answer: Choice C
Step-by-step explanation:
Events A and B are independent if the equation P(A∩B) = P(A) · P(B) holds true.
3/10≠3/5*1/4
so event A and B are not independent.
What is X:Compute
|x|=−4
Answer:
The answer is No Solution
Answer:
No solution
Step-by-step explanation:
There is no solution to this question.
Since the x is an absolute number, the answer cannot be -4. It would have to equal 4
So if that x was a -4 it would equal 4 since it is in absolute value brackets
Use the area to find the radius. If you could include steps that’ll be very helpful :)
Answer:
Radius = 13 m
Step-by-step explanation:
Formula for area of circle is given as:
[tex]A = \pi {r}^{2} \\ \\ \therefore \: 169\pi \: = \pi {r}^{2} \\ \\ \therefore \: {r}^{2} = \frac{169\pi }{\pi} \\ \\ \therefore \: {r}^{2} = 169 \\ \\ \therefore \: {r} = \pm \sqrt{169} \\ \\\therefore \: r = \pm \: 13 \: m \\ \\ \because \: radius \: of \: a \: circle \: can \: not \: be \: a \: negative \: \\quantity \\ \\ \huge \red{ \boxed{\therefore \: r = 13 \: m }}[/tex]
Use variation of parameters to find a general solution to the differential equation given that the functions y1 and y2 are linearly independent solutions to the corresponding homogeneous equation for t > 0. ty" + (2t - 1 )y' - 2y = 6t^2 e^-2t​; y1 = 22t −​1, y2 = e^-2t
Answer:
[tex]y_g(t) = c_1*( 2t - 1 ) + c_2*e^(^-^2^t^) - e^(^-^2^t^)* [ t^3 + \frac{3}{4}t^2 + \frac{3}{4}t ][/tex]
Step-by-step explanation:
Solution:-
- Given is the 2nd order linear ODE as follows:
[tex]ty'' + ( 2t - 1 )*y' - 2y = 6t^2 . e^(^-^2^t^)[/tex]
- The complementary two independent solution to the homogeneous 2nd order linear ODE are given as follows:
[tex]y_1(t) = 2t - 1\\\\y_2 (t ) = e^-^2^t[/tex]
- The particular solution ( yp ) to the non-homogeneous 2nd order linear ODE is expressed as:
[tex]y_p(t) = u_1(t)*y_1(t) + u_2(t)*y_2(t)[/tex]
Where,
[tex]u_1(t) , u_2(t)[/tex] are linearly independent functions of parameter ( t )
- To determine [ [tex]u_1(t) , u_2(t)[/tex] ], we will employ the use of wronskian ( W ).
- The functions [[tex]u_1(t) , u_2(t)[/tex] ] are defined as:
[tex]u_1(t) = - \int {\frac{F(t). y_2(t)}{W [ y_1(t) , y_2(t) ]} } \, dt \\\\u_2(t) = \int {\frac{F(t). y_1(t)}{W [ y_1(t) , y_2(t) ]} } \, dt \\[/tex]
Where,
F(t): Non-homogeneous part of the ODE
W [ y1(t) , y2(t) ]: the wronskian of independent complementary solutions
- To compute the wronskian W [ y1(t) , y2(t) ] we will follow the procedure to find the determinant of the matrix below:
[tex]W [ y_1 ( t ) , y_2(t) ] = | \left[\begin{array}{cc}y_1(t)&y_2(t)\\y'_1(t)&y'_2(t)\end{array}\right] |[/tex]
[tex]W [ (2t-1) , (e^-^2^t) ] = | \left[\begin{array}{cc}2t - 1&e^-^2^t\\2&-2e^-^2^t\end{array}\right] |\\\\W [ (2t-1) , (e^-^2^t) ]= [ (2t - 1 ) * (-2e^-^2^t) - ( e^-^2^t ) * (2 ) ]\\\\W [ (2t-1) , (e^-^2^t) ] = [ -4t*e^-^2^t ]\\[/tex]
- Now we will evaluate function. Using the relation given for u1(t) we have:
[tex]u_1 (t ) = - \int {\frac{6t^2*e^(^-^2^t^) . ( e^-^2^t)}{-4t*e^(^-^2^t^)} } \, dt\\\\u_1 (t ) = \frac{3}{2} \int [ t*e^(^-^2^t^) ] \, dt\\\\u_1 (t ) = \frac{3}{2}* [ ( -\frac{1}{2} t*e^(^-^2^t^) - \int {( -\frac{1}{2}*e^(^-^2^t^) )} \, dt] \\\\u_1 (t ) = -e^(^-^2^t^)* [ ( \frac{3}{4} t + \frac{3}{8} )] \\\\[/tex]
- Similarly for the function u2(t):
[tex]u_2 (t ) = \int {\frac{6t^2*e^(^-^2^t^) . ( 2t-1)}{-4t*e^(^-^2^t^)} } \, dt\\\\u_2 (t ) = -\frac{3}{2} \int [2t^2 -t ] \, dt\\\\u_2 (t ) = -\frac{3}{2}* [\frac{2}{3}t^3 - \frac{1}{2}t^2 ] \\\\u_2 (t ) = t^2 [\frac{3}{4} - t ][/tex]
- We can now express the particular solution ( yp ) in the form expressed initially:
[tex]y_p(t) = -e^(^-^2^t^)* [\frac{3}{2}t^2 + \frac{3}{4}t - \frac{3}{8} ] + e^(^-^2^t^)*[\frac{3}{4}t^2 - t^3 ]\\\\y_p(t) = -e^(^-^2^t^)* [t^3 + \frac{3}{4}t^2 + \frac{3}{4}t - \frac{3}{8} ] \\[/tex]
Where the term: 3/8 e^(-2t) is common to both complementary and particular solution; hence, dependent term is excluded from general solution.
- The general solution is the superposition of complementary and particular solution as follows:
[tex]y_g(t) = y_c(t) + y_p(t)\\\\y_g(t) = c_1*( 2t - 1 ) + c_2*e^(^-^2^t^) - e^(^-^2^t^)* [ t^3 + \frac{3}{4}t^2 + \frac{3}{4}t ][/tex]
The combined SAT scores for the students at a local high school are normally distributed with a mean of 1527 and a standard deviation of 291. The local college includes a minimum score of 1207 in its admission requirements. What percentage of students from this school earn scores that satisfy the admission requirement? P(X > 1207) =
Answer:
Step-by-step explanation:
Let x be the random variable representing the SAT scores for the students at a local high school. Since it is normally distributed and the population mean and population standard deviation are known, we would apply the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = standard deviation
From the information given,
µ = 1527
σ = 291
the probability to be determined is expressed as P(x > 1207)
P(x > 1207) = 1 - P(x ≤ 1207)
For x < 1208
z = (1207 - 1527)/291 = - 1.1
Looking at the normal distribution table, the probability corresponding to the z score is 0.16
P(x > 1207) = 1 - 0.16 = 0.84
Therefore, the percentage of students from this school earn scores that satisfy the admission requirement is
0.84 × 100 = 84%
Use the formula v = u + at to find the velocity when the initial velocity is 3 m/s the acceleration is 1.5 m/s the time is 7 s
[tex]answer \\ 13.5 \: m/s \\ given \\ initial \: velocity(u) = \: 3 \: m/s \\ acceleration(a) = 1.5 \: m/s ^2\\ time(t) = 7 \: second \\ now \\ v = u + at \\ or \: v = 3 + 1.5 \times 7 \\ \: or \: v = 3 + 10.5 \\ v = 13.5 \: m/s \\ hope \: it \: helps[/tex]
2y + 5x – z = 4y + 6x solve for y
(show work)
Answer:
y = -z/2 - x/2
Step-by-step explanation:
2y + 5x – z = 4y + 6x
-5x. -5x
2y - z = 4y + x
+z. +z
2y = 4y + z + x
-4y -4y
-2y = z + x
÷-2. ÷-2
y = -z/2 - x/2
A company manager for a tire manufacturer is in charge of making sure there is the least amount of defective tires. If the tire manufacturing process is working properly, the average weight of a tire for a 4-door sedan is normally distributed with a mean of 22 pounds and a standard deviation of 0.76 pounds. The manager decides to reject a tire as underweight if it falls more than 1.5 interquartile ranges below the lower quartile of the specified shipment of tires. What proportion of tires will be rejected by this process?
Answer:
0.347% of the total tires will be rejected as underweight.
Step-by-step explanation:
For a standard normal distribution, (with mean 0 and standard deviation 1), the lower and upper quartiles are located at -0.67448 and +0.67448 respectively. Thus the interquartile range (IQR) is 1.34896.
And the manager decides to reject a tire as underweight if it falls more than 1.5 interquartile ranges below the lower quartile of the specified shipment of tires.
1.5 of the Interquartile range = 1.5 × 1.34896 = 2.02344
1.5 of the interquartile range below the lower quartile = (lower quartile) - (1.5 of Interquartile range) = -0.67448 - 2.02344 = -2.69792
The proportion of tires that will fall 1.5 of the interquartile range below the lower quartile = P(x < -2.69792) ≈ P(x < -2.70)
Using data from the normal distribution table
P(x < -2.70) = 0.00347 = 0.347% of the total tires will be rejected as underweight
Hope this Helps!!!
The proportion of the tires that would be denied for being underweight through the given process would be:
[tex]0.347[/tex]% of the total tires will be rejected as underweight.
Given that,
Interquartile Range [tex]= 1.5[/tex]
Standard Deviation [tex]= 0.76[/tex]
Considering Mean = 0
and Standard Deviation = 1
Since lower quartile = -0.67448
Upper quartile = +0.67448
IQ range = 1.34896
To find,
The proportion of tires would be rejected due to being underweight through the process would be:
1.5 of Interquartile Range = 1.5 × [tex]1.34896 = 2.02344[/tex]
Now,
1.5 of the IQ range below the lower quartile [tex]= (lower quartile) - (1.5 of Interquartile range)[/tex]
[tex]= -0.67448 - 2.02344[/tex]
[tex]= -2.69792[/tex]
The proportion of tires that would be under 1.5 of the interquartile range below the lower quartile:
[tex]= P(x < -2.69792)[/tex] ≈ [tex]P(x < -2.70)[/tex]
Using data through the Normal Distribution Table,
[tex]P(x < -2.70)[/tex] [tex]= 0.00347[/tex]
[tex]= 0.347[/tex]%
Thus, 0.347% of the total tires would be rejected as underweight.
Learn more about "Proportion" here:
brainly.com/question/2548537
Please answer this correctly
Answer:
2
Step-by-step explanation:
Set the height of the bar to 2 since there are 2 numbers between 21-40.
Answer:
2 people.
Step-by-step explanation:
34 minutes and 40 minutes were recorded.
Therefore, 2 people.
The lifespan (in days) of the common housefly is best modeled using a normal curve having mean 22 days and standard deviation 5. Suppose a sample of 25 common houseflies are selected at random. Would it be unusual for this sample mean to be less than 19 days?
Answer:
Yes, it would be unusual.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
If [tex]Z \leq -2[/tex] or [tex]Z \geq 2[/tex], the outcome X is considered unusual.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
In this question, we have that:
[tex]\mu = 22, \sigma = 5, n = 25, s = \frac{5}{\sqrt{25}} = 1[/tex]
Would it be unusual for this sample mean to be less than 19 days?
We have to find Z when X = 19. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{19 - 22}{1}[/tex]
[tex]Z = -3[/tex]
[tex]Z = -3 \leq -2[/tex], so yes, the sample mean being less than 19 days would be considered an unusual outcome.
what is 0.035 as a simplified reduced fraction
Answer:
7/200
Step-by-step explanation:
0.035= 35/1000= 7*5/200*5=7/200
What role did youth play in the Civil Rights Movement?
Answer:
they played the pivotal role
Plz help me ASAP it’s important
Answer:
D. 6.3
Step-by-step explanation:
Well you can make a triangle with the line PQ with it's height as 2 and base as 6.
Then you can use the Pythagorean Theorem to find the length of PQ.
a²+b²=c²
2²+6²=c²
4+36=c²
40=c²
c²=40
Square root both sides
c=[tex]\sqrt{40}[/tex]
c≈6.3
Our answer is D. 6.3
Entrance to a prestigious MBA program in India is determined by a national test where only the top 10% of the examinees are admitted to the program. Suppose it is known that the scores on this test are normally distributed with a mean of 420 and a standard deviation of 80. Parul Monga is trying desperately to get into this program. What is the minimum score that she must earn to get admitted?
Answer:
The minimum score that she must earn to get admitted is 523.
Step-by-step explanation:
As the scores are normally distributed, we can calculate the probability using the z-score.
The distribution has a mean of 420 and a standard deviation of 80.
We have to calculate the z-score z* that satisfies:
[tex]P(z>z^*)=0.1[/tex]
This happens for z*=1.28155.
Then, we can calculate the score as:
[tex]X=\mu+z\cdot\sigma=420+1.28155\cdot 80=420+102.524=522.524[/tex]
What’s the correct answer for this question?
Answer:
B
Step-by-step explanation:
The triangular prism must have a larger base than the cylinder
A small college has 1460 students. What is the approximate probability that more than six students were born on Christmas day? Assume that birthrates are constant throughout the year and that each year has 365 days.
Answer:
The approximate probability that more than six students were born on Christmas day is P=0.105.
Step-by-step explanation:
This can be modeled as a binomial variable, with n=1460 and p=1/365.
The sample size n is the total amount of students and the probability of success p is the probability of each individual of being born on Christmas day.
As the sample size is too large to compute it as a binomial random variable, we approximate it to the normal distribution with the following parameters:
[tex]\mu=n\cdot p=1460\cdot (1/365)=4\\\\\sigma=\sqrt{n\cdot p(1-p)}=\sqrt{1460\cdot(1/365)\cdot(364/365)}=\sqrt{3.989}=1.997[/tex]
We want to calculate the probability that more than 6 students were born on Christmas day. Ww apply the continuity factor and we write the probability as:
[tex]P(X>6.5)[/tex]
We calculate the z-score for X=6.5 and then calculate the probability:
[tex]z=\dfrac{X-\mu}{\sigma}=\dfrac{6.5-4}{1.997}=\dfrac{2.5}{1.997}=1.252\\\\\\P(X>6.5)=P(z>1.252)=0.105[/tex]
You need a 55% alcohol solution. On hand, you have a 525 mL of a 45% alcohol mixture. You also have 90% alcohol mixture. How much of the 90% mixture will you need to add to obtain the desired solution? You will need _____mL of the 90% solution to obtain _____mL of the desired 55% solution.
Answer:
Let's call the amount of 90% solution x.
We can write:
45% * 525 + 90%x = 55%(x + 525)
0.45 * 525 + 0.9x = 0.55(x + 525)
Solving for x we get x = 150 so the first blank is 150 and the second blank is 525 + 150 = 675.
What is the value of n in the equation: 8n+9= -n+5?
Answer:
n = -1
Step-by-step explanation:
So first subtract 9 to both sides
8n = -n - 9
Now you want the n on one side and the constant on the other
so add the single n to the n side
9n = -9
Divide 9 to both sides to solve for n
n = -1
8. Mr. Azu invested an amount at rate of 12% per annum and invested another amount, GH¢
580.00 more than the first at 14%. If Mr. Azu had total accumulated amount of
GH¢2,358.60, how much was his total investment?
Answer:
GH¢. 18098.46
Step-by-step explanation:
Let the first investment giving 12% interest per annum be Bank A
Let the 2nd investment giving 10% per annum be bank B
Let the first amount invested be
GH¢. X and let the second amount invested be GH¢. X + 580
Thus; In bank A;
Principal amount in first = GH¢. x
rate = 12 %
time = 1 year
Formula for simple interest = PRT/100
Where P is principal, R is rate and T is time.
So, interest in his investment = 12X/100 = 0.12X
while in bank B;
principal amount = GH¢. X + 580
rate = 14%
time = 1 yr
So, interest in his investment = [(X + 580) × 14]/100
= 0.14(X + 580)
So, total accumulated interest is;
0.12X + 0.14(X + 580) = 0.12X + 0.14X + 81.2 = 0.26X + 81.2
Now, we are given accumulated interest = GH¢. 2,358.60
Thus;
2358.60 = (0.26X + 81.2)
2358.6 - 81.2 = 0.26X
X = 2277.4/0.26
X = 8759.23
So,
first amount invested = GH¢. 8759.23
Second amount invested = GH¢. 8759.23 + GH¢. 580 = GH¢. 9339.23
Total amount invested = GH¢. 8759.23 + GH¢. 9339.23 = GH¢. 18098.46
i need help asap!!!!!
Answer:
31 degrees
Step-by-step explanation:
Since RPS and QPR make up QPS, the sum of their angle measures must be 47. Therefore:
3x-38+7x-95=47
10x-133=47
10x=180
x=18
QPR=7(18)-95=126-95=31
Hope this helps!
These tables of values represent continuous functions. For which function will the y-values be the greatest for very large values of x?
Answer:
C
Step-by-step explanation:
The function of table A can be written as ...
y = 100x -92
__
The function of table B can be written as ...
y = 10x +446
__
The function of table C can be written as ...
y = (5/3)·3^x
__
The function of table D can be written as ...
y = 2x +413
__
The exponential function of Table C will have the largest y-values for any value of x greater than 6.
_____
Comment on the functions
When trying to determine the nature of the function, it is often useful to look at the differences of the y-values for consecutive x-values. Here, the first-differences are constant for all tables except C. That means functions A, B, D are linear functions.
If the first differences are not constant, one can look at second differences and at ratios. For table C, we notice that each y-value is 3 times the previous one. That constant ratio means the function is exponential, hence will grow faster than any linear function.
Answer:
yes, what the other user is correct i just took the quiz
Step-by-step explanation:
Write a linear function f with f(−2)=6 and f(0)=−4 .
Answer:
y = -5(x) - 4
Step-by-step explanation:
Use the equation of a line and substitution.
Information given:
point 1: (-2,6)
x1 = -2 and y1 = 6
point 2: (0,4)
x2 = 0 and y2 = 4
Equation of a line: y = m(x) + b
m = slope
To find slope, you do the equation of a linear slope, which is:
m = [tex]\frac{rise}{run}[/tex] in other words m = [tex]\frac{Y2 - Y1}{X2-X1}[/tex]
plug in your values
[tex]\frac{6-(-4)}{-2-0}[/tex]
= -5
Great, we've found slope, now to find b
plug in the slope you found: y = -5(x) + b
Plug in and solve for each point given, aka (x,y) into the linear equation for both points.
FIRST POINT:
6 = -5(-2) + b
6 = 10 + b
6 - 10 = b
b = -4
SECOND POINT:
-4 = -5(0) + b
-4 = 0 + b
-4 - 0 = b
b = -4
We got -4 for both, meaning that this equation is correct, so if you add in b, your final equation will be y = -5(x) - 4.
Plug this into desmos.com/calculator, and you'll see this linear equation runs through both points given in the problem.
Answer:
f(x)=-5x-4
Step-by-step explanation:
You are given two points (-2, 6) and (0, -4)
Find the slope: m=(-4-6)/[(0-(-2)]=-5
So you have y=-5x+b
next, find the y intercept b.
the y intercept is when x=0. in this case, the y intercept is -4
so the linear function is f(x)=-5x-4
The differential equation below models the temperature of a 91°C cup of coffee in a 17°C room, where it is known that the coffee cools at a rate of 1°C per minute when its temperature is 70°C. Solve the differential equation to find an expression for the temperature of the coffee at time t. dy dt = − 1 53 (y − 17)\
Answer:
[tex]t \approx 17.690\,min[/tex]
Step-by-step explanation:
This differential equation is a first order linear differential equation with separable variables, whose solution is found as follows:
[tex]\frac{dy}{dt} = - \frac{1}{53} \cdot (y - 17)[/tex]
[tex]\frac{dy}{y-17} = -\frac{1}{53} \, dt[/tex]
[tex]\int\limits^{y}_{y_{o}} {\frac{dy}{y-17} } = -\frac{1}{53} \int\limits^{t}_{0}\, dx[/tex]
[tex]\ln \left |\frac{y-17}{y_{o}-17} \right | = -\frac{1}{53} \cdot t[/tex]
[tex]\frac{y-17}{y_{o}-17} = e^{-\frac{1}{53}\cdot t }[/tex]
[tex]y = 17 + (y_{o} - 17) \cdot e^{-\frac{1}{53}\cdot t }[/tex]
The solution of the differential equation is:
[tex]y = 17 + 74\cdot e^{-\frac{1}{53}\cdot t }[/tex]
Where:
[tex]y[/tex] - Temperature, measured in °C.
[tex]t[/tex] - Time, measured in minutes.
The time when the cup of coffee has the temperature of 70 °C is:
[tex]70 = 17 + 74 \cdot e^{-\frac{1}{53}\cdot t }[/tex]
[tex]53 = 74 \cdot e^{-\frac{1}{53}\cdot t }[/tex]
[tex]\frac{53}{74} = e^{-\frac{1}{53}\cdot t }[/tex]
[tex]\ln \frac{53}{74} = -\frac{1}{53}\cdot t[/tex]
[tex]t = - 53\cdot \ln \frac{53}{74}[/tex]
[tex]t \approx 17.690\,min[/tex]
John works 21 hours a week and earns $157.50. How much does john earn per hour?
Answer:
D. $7.50
Step-by-step explanation:
$157.50 / 21 hours = $7.50 per hour