Answer:
C
Step-by-step explanation:
The number of people who have heard a rumor is modeled by the logistic function:
[tex]\displaystyle f(x)=\frac{260}{1+23e^{-0.06x}}[/tex]
And we want how many days has passed since the rate at which the rumor spread began to decrease.
First, the numerator tells us that the total number of people who will have heard the rumor by the end is 260.
Recall that the point of maximum growth is always half of the maximum capacity.
In this case, that point will be 260/2 = 130.
For a logistic function, the rate of all values to the left of the halfway point is increasing, (i.e. concave up), while the rate of all values to the right is decreasing (i.e. concave down). Therefore, we can solve for x when f(x) = 130:
[tex]\displaystyle 130=\frac{260}{1+23e^{-0.06x}}[/tex]
Cross-multiply:
[tex]130(1+23e^{-0.06x}})=260[/tex]
Distribute:
[tex]130+2990e^{-0.06x}=260[/tex]
Solving for x:
[tex]2990e^{-0.06x}=130[/tex]
Therefore:
[tex]\displaystyle e^{-0.06x}=\frac{130}{2990}=\frac{1}{23}[/tex]
Taking the natural log of both sides:
[tex]\displaystyle -0.06x=\ln\Big(\frac{1}{23}\Big)[/tex]
Therefore:
[tex]\displaystyle x=\frac{\ln(1/23)}{-0.06}\approx52.3[/tex]
After about 52.3 days, the rate at which the rumor started spreading will begin to decrease.
Evaluate the expression.
3×2⁴
The ratio of cats to dogs is 5:4 in Riverside. If there are 20 dogs, how many cats live in Riverside?
Select one:
25
20
30
16
Answer:
25
Step-by-step explanation:
c to d is 5 to 4
5x5=25
fffff
Answer:
25
Step-by-step explanation:
We need to divide 20 by 4 to see how much 1 equals in this problem.
20÷4=5
5 equals 1
Now we add 5 to 20 because the ratio is 5:4.
20+5=25
Our answer is 25.
[tex]1/5(6+3+1)^{2}[/tex]
Anyone help?
.....hgzgxhlflhf
Answer:
it should be 152, can i please get brainliest
Step-by-step explanation:
Using the expression you found in part a, how many minutes will it take to make and pack an order for 15 parts?
Answer:
It will take 40 minutes to make and pack an order for 15 parts.
Step-by-step explanation:
That's the answer.
Answer:
It will take 40 minutes to make and pack an order for 15 parts.
Step-by-step explanation:
Plz help it’s due tomorrow
Answer:
x=121 degrees
Step-by-step explanation:
Sorry if my work is a bit messy. If you need me to rewrite it i can
what is the measure of angle 1?
a. 36
b. 86
c. 89
d. 94
Answer:
D, 94
Step-by-step explanation:
Angles of a triangle add up to 180 degrees. 180 - 29 - 65 = 86 Angles 1 and 2 add up to 180 degrees. 86 = 2 180 - 86 = 94 94 = 1
Hope this helps! If it did, please mark it as brainliest! It would help me out a lot! :D
5. For the final touches, John wanted to paint the house using 3 colors. If he has 5
gallons of paint for each color, write an equation for the total number of gallons of
paint he has?
Answer:
3 x 5 = 15
Step-by-step explanation:
To explain this in short, John has 5 gallons of 3 colors, meaning that 3 x 5 = 15 would be the appropriate equation to finish this question. I hope this helps!
Which is the graph of the inequality: y is less than (1/2x - 2)^3
Answer:
A
Step-by-step explanation:
Tom is 10 years younger than Becky. In two years, Becky will be twice as old as Tom. How old is Tom now?
Answer:
20
Step-by-step explanation:
Answer:
tom is 8 and becky is 18 now
Step-by-step explanation:
in two years becky would be 20 and tom will be 10
hope this helps
help!!!!!!!!!!!!!!!!
Write the equation of a line in slope-intercept form if m=2 and b=8.
Answer:
y=2x+8
Step-by-step explanation:
The slope intercept form is:
y=mx+b
with m and b already given, just plug in m and b and you will get your answer.
what is 2 3/4 as a improper fraction
Answer:
11/4
Step-by-step explanation:
2x4=8
3+8=11
11/4
Which of the following options have the same value as 96% of 25?
Choose 2 answers:
96
100
• 25
Pro
B
0.96 - 25
Tea
0.96 . 0.25
96 25
100 100
96 - 25
Answer:
A
Step-by-step explanation:
yyjvgyujjjjuyrcjkoiffffgy
What is the volume of this cube?
Answer:
50
Step-by-step explanation:
im not that sure sorry
Answer:
The answer is 0.125.
Step-by-step explanation:
The forumla to find volume of a cube is a3. (Let a repersent 0.5) 0.5x0.5x0.5 is 0.125
Find the volume of this rectangular pyramid.
Be sure to include the correct unit in your answer.
6yd,3yd,7yd,
Answer:
the volume is 42 yds
Step-by-step explanation:
multiply 6x3x7=126
divide 126 by 3
126/3=42
The ratio of two numbers is 7 to 5. The sum of the numbers is 36. What are the numbers?
A. 26 and 10
B. 18 and 8
C. 21 and 15
D. 14 and 10
Answer:
Step-by-step explanation:
a/b=7/5
a=7b/5
a+b=36, using 7b/5 for a we have
7b/5+b=36
7b/5+5b/5=36
12b/5=36
12b=180
b=15, and since a=7b/5
a=7(15)/5
a=21
So the numbers are 21 and 15
Answer:
C is the correct answer please like for more
If US $1.00 is equivalent to EC $ 2.70, how much in US would one get from EC 297.00?
how could i find the value of this expression?
Answer:
you plug in the numbers
Step-by-step explanation:
Please mark brainliest!!
Answer:
√x⁴-y²
x²-y²
(x+y)(x-y)
when
x=3
y=-6
√x⁴-y²=(3-6)(3+6)=-3×9=-27 is your answer
Corey records the temperature in degrees Celsius each morning. At 8am the temperature was 3 degrees below zero. It rose 3 degrees by 10am. Which equation shows the change in temperature from 8am to 10am?
A 3+3=6
B-3+3=0
C-3+3= -6
D-3-3= -6
what is it step by step 7a - 4a when a = 8
Answer:
Step-by-step explanation:
7a - 4a
a = 8
so
7(8) - 4(8)
56 - 32 = 23
FINALLY! Someone asks for a step-by-step! TYSM!
Since a=8, we ae going to replace the a variables with 8.
7(8)-4(8)
7x8=56
4x8=32.
Now we subtract.
56-32=24.
---
hope it helps
A cone has a volume of 350 cubic meters. The area of the baseis
70 square meters. What is the height of the cone?
Answer:
The height is 15
Joe ran 1 1/4 laps in 2 minutes. How many laps did Joe run on average per minute?
Answer
2.5/4
Step-by-step explanation:
If you do 1 1/4 divided by 2 that would equal 2.5/4 I hope that helps!
Nora made 15 gallons of lemonade for a community picnic. She served 100 pints to the people. How many pints are leftover? Please help!
Answer:
There are 8 pints to a gallon so she makes 120 gallons, and since she served 100 pints then there are 20 pints left over.
Brainliest please?
The recipe calls for 2 2/4 but jams only have 1/4 how many cups do jams need to measure out 2 2/4 cups of raisins
Answer:
brainliest
Step-by-step explanation:
she needs altogether 2 2/4.
that is 2 wholes and 2/4 fraction.
if we consider using 1/4 cup, 1 whole is made of four quarter cups.
Therefore 2 wholes require eight quarter cups. then theres a remaining fraction of 2/4 which is equivalent to two quarter cups.
1/4 + 1/4 = 2/4. therefore altogether 8 + 2 = 10 of the 1/4 cups are required for the recipe.
10 of 1/4 cups are needed
A rectangle measures 3 1/4 inches by 3 3/4 inches. What is the area
Answer:
12.1875 or 195/16 or 12 3/16
Step-by-step explanation:
All you must do is multiply them by each other
hope this helps
Answer:
12.19 inches
Step-by-step explanation:
please mark brainliest
We wish to modify the cellular telephone coding system in order to reduce the number of errors. In particular, if there are two or three zeroes in the received sequence of 5 bits, we will say that a deletion (event D) occurs. Otherwise, if at least 4 zeroes are received, then the receiver decides a zero was sent. Similarly, if at least 4 ones are received, then the receiver decides a one was sent. We say that an error occurs if either a one was sent and the receiver decides zero was sent or if a zero was sent and the receiver decides a one was sent. For this modified protocol, what is the probability P[E] of an error? What is the probability P[D] of a deletion?
Solution :
Here, we have 5 trails that corresponds to the 5 times the binary symbol is sent. On each trail, success is said to occur when the binary symbol is received correctly. The probability of a success is p = 1 - q = 0.9 and q = 0.1
Now if the 0 is being transmitted, then the 0 is sent 5 number of times and then we call the decoding a 0 success. Let the repeated transmission are independent. In this case, we have 5 trails. Let each repeated bit the receiver decodes as 1 a success, using the binomial probabilities. We using the [tex]$S_{k,5}$[/tex] to denote an event of [tex]$k$[/tex] successes in the 5 trails, then the probability k are decoded at the receiver is:
[tex]$P[S_{k,5}]=\binom{5}{k}p^k(1-p)^{5-k}$[/tex]
[tex]$=\binom{5}{k}(0.9)^k(1-0.9)^{5-k}$[/tex]
[tex]$=\binom{5}{k}(0.9)^k(0.1)^{5-k}$[/tex]
Here, k = 1, 2, 3, 4, 5
The probability of the transmitted bit to be decoded correctly is:
[tex]$P[C]=P[S_{5,5}]+P[S_{2,5}]$[/tex]
[tex]$=\binom{5}{3}(0.9)^5(0.1)^{0}+\binom{5}{4}(0.9)^4(0.1)^1$[/tex]
[tex]$=(0.9)^5+5(0.9)^4(0.1)^1$[/tex]
= 0.91854
The probability that the deletion occurs is
[tex]$P[D]=P[S_{3,5}]+P[S_{2,5}]$[/tex]
[tex]$=\binom{5}{3}(0.9)^3(0.1)^{2}+\binom{5}{2}(0.9)^2(0.1)^3$[/tex]
[tex]$=10(0.9)^3(0.1)^2+10(0.9)^2(0.1)^3$[/tex]
= 0.081
The probability of an error is
[tex]$P[E]=P[S_{1,5}]+P[S_{0,5}]$[/tex]
[tex]$=\binom{5}{1}(0.9)^1(0.1)^{4}+\binom{5}{0}(0.9)^0(0.1)^5$[/tex]
[tex]$=5(0.9)^1(0.1)^4+(0.1)^5$[/tex]
= 0.00046
Anyone know this please I really need help
A rocket fired upward from some initial distance above the ground. Its height (in feet) h, above the ground t seconds after it is fired is given by h(t)=-16t^2+160t+384
What is the rockets maximum height?
After it is fired, The rocket reaches the ground at t=____ seconds
Answer:
Part A)
784 feet in the air (after five seconds).
Part B)
After 12 seconds.
Step-by-step explanation:
The height h (in feet) of a rocket t seconds after being fired is modeled by the function:
[tex]h(t)=-16t^2+160t+384[/tex]
Part A)
We want to find the rocket's maximum height.
Since our function is a quadratic, the maximum height will occur at its vertex. The vertex of a quadratic is given by:
[tex]\displaystyle \Big(-\frac{b}{2a}\, f\Big(-\frac{b}{2a}\Big)\Big)[/tex]
In this case, a = -16, b = 160, and c = 384.
So, the vertex occurs at:
[tex]\displaystyle t=-\frac{160}{2(-16)}=\frac{160}{32}=5\text{ seconds}[/tex]
The maximum height is reached after five seconds.
Then the maximum height is:
[tex]h(t)_\text{max}=h(5)=-16(5)^2+160(5)+384=784\text{ feet}[/tex]
Part B)
When the rocket reaches the ground, its height h above the ground will be 0. Hence:
[tex]h(t)_\text{ground}=0=-16t^2+160t+384[/tex]
Solve for t. We can first divide both sides by -16:
[tex]t^2-10t-24=0[/tex]
Factor:
[tex](t-12)(t+2)=0[/tex]
Zero Product Property:
[tex]t-12=0\text{ or } t+2=0[/tex]
Solve for each case:
[tex]t=12\text{ or } t=-2[/tex]
Time cannot be negative. Hence, our only solution is:
[tex]t=12\text{ seconds}[/tex]
The rocket reaches the ground 12 seconds after it is fired.
What is g(x)?
A. g(x) = -2
B. g(x) = -11
C. g(x) = -x
D. g(x) = -x
WILL MARK BRAINIEST!!
Step-by-step explanation:
g(x) = -X^2
which isn't an option.