Animal populations are not capable of unrestricted growth because of limited habitat and food supplies. Under such conditions the population follows a logistic growth model: P(t) = d 1 + ke−ct where c, d, and k are positive constants. For a certain fish population in a small pond d = 1200, k = 11, c = 0.2, and t is measured in years. The fish were introduced into the pond at time t = 0. (a) How many fish were originally put in the pond? 100 Correct: Your answer is correct. fish (b) Find the population after 10, 20, and 30 years. (Round your answers to the nearest whole number.) 10 years 1 Changed: Your submitted answer was incorrect. Your current answer has not been submitted. fish 20 years fish 30 years fish (c) Evaluate P(t) for large values of t. What value does the population approach as t → [infinity]? P(t) =
Answer:
(a) 100 fishes
(b) t = 10: 483 fishes
t = 20: 999 fishes
t = 30: 1168 fishes
(c)
[tex]P(\infty) = 1200[/tex]
Step-by-step explanation:
Given
[tex]P(t) =\frac{d}{1+ke^-{ct}}[/tex]
[tex]d = 1200\\k = 11\\c=0.2[/tex]
Solving (a): Fishes at t = 0
This gives:
[tex]P(0) =\frac{1200}{1+11*e^-{0.2*0}}[/tex]
[tex]P(0) =\frac{1200}{1+11*e^-{0}}[/tex]
[tex]P(0) =\frac{1200}{1+11*1}[/tex]
[tex]P(0) =\frac{1200}{1+11}[/tex]
[tex]P(0) =\frac{1200}{12}[/tex]
[tex]P(0) = 100[/tex]
Solving (a): Fishes at t = 10, 20, 30
[tex]t = 10[/tex]
[tex]P(10) =\frac{1200}{1+11*e^-{0.2*10}} =\frac{1200}{1+11*e^-{2}}\\\\P(10) =\frac{1200}{1+11*0.135}=\frac{1200}{2.485}\\\\P(10) =483[/tex]
[tex]t = 20[/tex]
[tex]P(20) =\frac{1200}{1+11*e^-{0.2*20}} =\frac{1200}{1+11*e^-{4}}\\\\P(20) =\frac{1200}{1+11*0.0183}=\frac{1200}{1.2013}\\\\P(20) =999[/tex]
[tex]t = 30[/tex]
[tex]P(30) =\frac{1200}{1+11*e^-{0.2*30}} =\frac{1200}{1+11*e^-{6}}\\\\P(30) =\frac{1200}{1+11*0.00247}=\frac{1200}{1.0273}\\\\P(30) =1168[/tex]
Solving (c): [tex]\lim_{t \to \infty} P(t)[/tex]
In (b) above.
Notice that as t increases from 10 to 20 to 30, the values of [tex]e^{-ct}[/tex] decreases
This implies that:
[tex]{t \to \infty} = {e^{-ct} \to 0}[/tex]
So:
The value of P(t) for large values is:
[tex]P(\infty) = \frac{1200}{1 + 11 * 0}[/tex]
[tex]P(\infty) = \frac{1200}{1 + 0}[/tex]
[tex]P(\infty) = \frac{1200}{1}[/tex]
[tex]P(\infty) = 1200[/tex]
Can u guys help me pls ill give u 20 points
Answer:
Its either L or N im not sure but if i had to guess out of the two i think its L.
Step-by-step explanation:
Given m= <3,7> and n=<1,5> what is m+3n?
Answer:
i thought it was one number
Step-by-step explanation:
My cousin needs help with this question.
Answer:
3 feet per minute
Step-by-step explanation:
Look at an easy to read point on a grid line intersection.
Then find the slope. Slope = constant of proportionality.
For example, look at point (2, 6) which means that when time = 2 minutes, distance = 6 feet.
(6 ft)/(2 sec) = 3 feet per minute
Answer: 3 feet per minute
Selena is a freelance graphic artist who charges $65 per hour for her services. A client paid her $195 for her last project. The equation below represents this situation.
65h = 195
For how many hours did Selena work on that project?
Answer: 3 hours
Step-by-step explanation:
195/65=3
Answer:
3
Step-by-step explanation:
$195 divided by $65 is 3 hours of work
I keep looking and I can’t find the answer
Answer:
B
Step-by-step explanation:
sInce his average is equal or greater than league's average
PLEASE HELPPO?!!!! Look at the attachment below
Answer:
157
Step-by-step explanation:
just trust me bro
I need help asap please! 20 points!
Graph the parabola.
y=x²–2x-4
Plot five points on the parabola: the vertex, two points to the left of the vertex, and two points to the right of the vertex. Then click on the graph-a-function
button
This is the graph I hope this helps
A company that manufactures electronic components wants to know the mean discharge time of one particular type of capacitor that it makes. In order to estimate this value, they randomly select 100 capacitors and measure how long they take to discharge. The mean of this sample was 7.25 seconds with a standard deviation of 0.15 seconds. Assuming that this distribution is normal, construct a 99% confidence interval to estimate the mean discharge time for all capacitors of this type. Is this question asking for a confidence interval or hypothesis test
Answer:
99% confidence interval to estimate the mean discharge time for all capacitors of this type
(7.2146, 7.2854)
Step-by-step explanation:
Step(i):-
Given that the sample size 'n' = 100
Given that the mean of sample x⁻ = 7.25 seconds
Given that the standard deviation of the sample (S) = 0.15 seconds
Level of significance = 0.01
Degrees of freedom = n-1 =100-1 =99
t₀.₀₁ , ₉₉ = 2.3646
We have to find that the 99% of the confidence interval of the mean
Step(ii):-
99% confidence interval to estimate the mean discharge time for all capacitors
[tex](x^{-} - t_{0.01 , 99} \frac{S}{\sqrt{n} } , x^{-} + t_{0.01 , 99} \frac{S}{\sqrt{n} } )[/tex]
[tex](7.25 - 2.3646 \frac{0.15}{\sqrt{100} } , 7.25 + 2.3646 \frac{0.15}{\sqrt{100} } )[/tex]
(7.25 - 0.0354 , 7.25 + 0.0354)
(7.2146, 7.2854)
Final answer:-
99% confidence interval to estimate the mean discharge time for all capacitors of this type
(7.2146, 7.2854)
I have to go to a few places but my friend needs help with this specific equation!
Thank you!
~Hocus Pocus
Answer:
Hello, this would be a vertical angle graph. Since this graph is a supplementary graph since it stretches about 180 degrees, you would take both 7x and x+20 and set it equal to 180 like this:
7x+x+20=180
Then, you combine the xs and you would get this:
8x+20=180
Then, subtract 20 from both sides like this:
8x=160
Lastly, you would divide 8 by both sides and get x which is:
x=20
Step-by-step explanation:
I hope this helped you!
What is the equation of the line shown in the graph at the right?
Please hurry and help me
Answer:
The last option is your answer
Step-by-step explanation:
how many oz do you think this cup is
Answer:
I'm gonna say 12??
Step-by-step explanation:
Am I close?
Have a nice day! <3
A group of 15 people were surveyed about the month they were
born. How many of the students were born in March?
.
3/5 born in September
1/3 born in December
IF PASSPORT is written as RCUURQTV, then how will BOOKLET be coded?
Answer: DQQMNGV
Step-by-step explanation: Each letter is shifted two letters to the right on a letter strip (a -> b -> c), so BOOKLET would be DQQMNGV.
Hope this helps!
Answer please and explain
Answer:
C=84
Step-by-step explanation:
Since you use 3 for pi. You plug the radius into the formula. C=2×3x14=84
A family spends 1/10 of it's annual income for housing 1/4 for food and clothing 1/5 for general expenses and 2/15 for entertainment what fractional part of their income is spent on these items altogether.
Answer:
The family spends 41/60 of its income on these items altogether.
Step-by-step explanation:
Given that a family spends 1/10 of it's annual income for housing, 1/4 for food and clothing, 1/5 for general expenses and 2/15 for entertainment, to determine what fractional part of their income is spent on these items altogether the following calculation must be performed:
10, 4, 5, and 15 have a common least multiple at 60.
1/10 = 6/60
1/4 = 15/60
1/5 = 12/60
2/15 = 8/60
6 + 15 + 12 + 8 = 41
Therefore, the family spends 41/60 of its income on these items altogether.
30 POINTS!!!!! I WILL GIVE BRAINLIEST!!!!!!
What is the measure of angle PQR?
Answer:
40
Step-by-step explanation:
It tells you what Q, R is for the opening. That means that it is 40
The measure of angle PQR is 70 degrees
We have a right triangle - r is 90 degrees
based on geometric rules: angle RPQ = 20
40 : 2
90 + 20 = 110
110 + x = 180
What is the perimeter of the triangle?
The perimeter of the triangle is 180 degrees
The triangle has 180 degrees.
This means that 180 - 110 =70 degrees.
The measure of angle PQR is 70 degrees.
In this experiment researchers randomly assigned smokers to treatments. Of the 193 smokers taking a placebo, 29 stopped smoking by the 8th day. Of the 266 smokers taking only the antidepressant buproprion, 82 stopped smoking by the 8th day. Calculate the estimated standard error for the sampling distribution of differences in sample proportions.
Answer:
The estimated standard error for the sampling distribution of differences in sample proportions is 0.0382.
Step-by-step explanation:
To solve this question, we need to understand the Central Limit Theorem and subtraction of normal variables.
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.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction of normal variables:
When we subtract normal variables, the mean is the subtraction of the means, while the standard error is the square root of the sum of the variances:
Of the 193 smokers taking a placebo, 29 stopped smoking by the 8th day.
This means that:
[tex]p_S = \frac{29}{193} = 0.1503[/tex]
[tex]s_S = \sqrt{\frac{0.1503*0.8497}{193}} = 0.0257[/tex]
Of the 266 smokers taking only the antidepressant buproprion, 82 stopped smoking by the 8th day.
This means that:
[tex]p_A = \frac{82}{266} = 0.3083[/tex]
[tex]s_A = \sqrt{\frac{0.3083*0.6917}{266}} = 0.0283[/tex]
Calculate the estimated standard error for the sampling distribution of differences in sample proportions.
[tex]s = \sqrt{s_S^2 + s_A^2} = \sqrt{0.0257^2 + 0.0283^2} = 0.0382[/tex]
The estimated standard error for the sampling distribution of differences in sample proportions is 0.0382.
Find 0% of 44:
Find 100% of 44:
Find 50% of 44:
Find 25% of 44:
Find 75% of 44:
Answer:
0% of 44=0
100% if 44=44
50% of 44=22
25% of 44=11
75% of 44=33
Which equation goes with the t-chart below?
Answer:
y = 2 x^2 + 5
Step-by-step explanation:
y = 2x^2 + 5
y = 2(-2)^2 + 5
y= 2(4) + 5
y = 8 + 5
y = 13
you can try for yourself using the other values
HELPPPP ITS TIMEDDD WILL GIVE BRAINLYISTTTT
$102 headphones, 7.5% tax
Answer:
You are correct the tax would be that
Step-by-step explanation:
9 decreased by 4 times a number
Answer:
4x - 9
Step-by-step explanation:
4 times a number means 4x
9 decreased by means -9
Combined:
4x - 9
Answer:
9 - 4x
Step-by-step explanation:
this is so easy
Nevaeh invested $660 in an account paying an interest rate of 3% compounded
continuously. Jonathan invested $660 in an account paying an interest rate of 3 %
compounded monthly. After 14 years, how much more money would Nevaeh have in
her account than Jonathan, to the nearest dollar?
Answer:
19
Step-by-step explanation:
Rate 1: 3
4
1
%=3+1/4=
\,\,3.25\%\rightarrow 0.0325
3.25%→0.0325
\text{Rate 2: }3\tfrac{1}{8}\%=3+1/8=
Rate 2: 3
8
1
%=3+1/8=
\,\,3.125\%\rightarrow 0.03125
3.125%→0.03125
\text{Calculate Final Amount for Nevaeh}
Calculate Final Amount for Nevaeh
\overline{\phantom{\text{Calculate Final Amount for Nevaeh}}}
Calculate Final Amount for Nevaeh
\text{Compounded Continuously:}
Compounded Continuously:
A=Pe^{rt}
A=Pe
rt
P=660\hspace{35px}r=0.0325\hspace{35px}t=14
P=660r=0.0325t=14
Given values
A=660e^{0.0325(14)}
A=660e
0.0325(14)
Plug in
A=660e^{0.455}
A=660e
0.455
Multiply
A=1040.2744
A=1040.2744
Use calculator (with e button)
\text{Calculate Final Amount for Jonathan}
Calculate Final Amount for Jonathan
\overline{\phantom{\text{Calculate Final Amount for Jonathan}}}
Calculate Final Amount for Jonathan
\text{Compounded Monthly:}
Compounded Monthly:
A=P\left(1+\frac{r}{n}\right)^{nt}
A=P(1+
n
r
)
nt
Compound interest formula
P=660\hspace{35px}r=0.03125\hspace{35px}t=14\hspace{35px}n=12
P=660r=0.03125t=14n=12
Given values
A=660\left(1+\frac{0.03125}{12}\right)^{12(14)}
A=660(1+
12
0.03125
)
12(14)
Plug in values
A=660(1.0026042)^{168}
A=660(1.0026042)
168
Simplify
A=1021.6468
A=1021.6468
Use calculator
\text{How much more money Nevaeh has:}
How much more money Nevaeh has:
1040.2744-1021.6468
1040.2744−1021.6468
18.6276
18.6276
\$ 19
$19
What is the equation of the graph below?
y = sec(x) + 2
y = csc(x) + 2
y = csc(x + 2)
y = sec(x + 2)
Answer:
y = csc(x) + 2
Step-by-step explanation:
The equation for the given graph is y = csc(x) + 2
What is an equation of a graph?'In graph theory, Graph equations are equations in which the unknowns are graphs. One of the central questions of graph theory concerns the notion of isomorphism. The graphs are expressed differently in terms of graph equations.'
According to the given problem,
We know, periodicity of a.csc( bx + c ) + d = [tex]\frac{periodicity of cscx}{[b]}[/tex]
The periodicity of csc(x) is 2π,
⇒ [tex]\frac{2\pi }{1}[/tex]
= 2π
Hence, we can conclude, the equation y = csc(x) + 2 represents the given graph.
Learn more about equations of graphs here: https://brainly.com/question/24866278
#SPJ2
A picture is to be printed onto a sheet of paper with dimensions of 81/2 x 11 inches, A margin of 1 1/2 inches is to be left on all sides of the picture. What is the area of the printed picture?
Answer:
The area of the printed picture is 172.5 square inches.
Step-by-step explanation:
Since a picture is to be printed onto a sheet of paper with dimensions of 81/2 x 11 inches, and a margin of 1 1/2 inches is to be left on all sides of the picture, to determine what is the area of the printed picture the following calculation must be carried out, knowing that the area of a rectangle is equal to the base multiplied by the height:
81/2 = 40.5
1/2 = 0.5
40.5 - 1.5 x 4 = 34.5
11 - 1.5 x 4 = 5
34.5 x 5 = 172.5
Therefore, the area of the printed picture is 172.5 square inches.
Help me I have this due today!!!
Answer:
The answer is 21/25.
Step-by-step explanation:
I hope this helps! Have a great rest of your day!
Please help very urgent
Answer:
it depends how many weeks look below
Step-by-step explanation:
1 week=$100.00
2 weeks=$115.00
3 weeks=$130.00
4 weeks=$145.00
and so on
pretty much every week you go up, she earns 15 bucks
hope this helps! have a good day :)
divide 12 unto two parts such that
their product is 35