OLVE
(a) 3^2x+1=9^
2x-1
Answer:
x=2
Step-by-step explanation:
you first have to make the bases the same
3^2x+1=9^2x-1
3^2x+1=3^2(2x-1) if you make the bases the same you will use 3^2 because it's equal to 9
3^2x+1=3^4x-2
2x+1=4x-2
2x-4x=-2-1
-2x/-2=-4/-2
x=2
I hope this helps
A bacteria culture grows with a constant relative growth rate. After 2 hours there are 400 bacteria and after 8 hours the count is 50,000.
(a) Find the initial population. P(0) = 80 )ãbacteria
(b) Find an expression for the population after t hours. r(t) = 180( 125(6 Plt) =180(125(2))-
(c) Find the number of cells after 7 hours. (Round your answer to the nearest integer.) P(7)=72.358- bacteria
(d) Find the rate of growth after 7 hours. (Round your answer to the nearest integer.) P(7) 2x bacteria/hour
(e) When will the population reach 200,000? (Round your answer to one decimal place.) hours
Answer:
a) P(0) = 80
b) [tex]P(t) = 80(2.2361)^t[/tex]
c) 22,363 cells.
d) The rate of growth after 7 hours is of 18,000 bacteria per hour.
e) 9.7 hours.
Step-by-step explanation:
A bacteria culture grows with a constant relative growth rate.
This means that the population is given by:
[tex]P(t) = P(0)(1+r)^t[/tex]
In which P(0) is the initial population and r is the growth rate, as a decimal.
After 2 hours there are 400 bacteria and after 8 hours the count is 50,000.
This means that in 6 hours, the population went from 400 bacteria to 50,000 bacteria. We use this to find r. So
[tex]50000 = 400(1+r)^6[/tex]
[tex](1+r)^6 = \frac{50000}{400}[/tex]
[tex](1+r)^6 = 125[/tex]
[tex]\sqrt[6]{(1+r)^6} = \sqrt[6]{125}[/tex]
[tex]1 + r = 125^{\frac{1}{6}}[/tex]
[tex]1 + r = 2.2361[/tex]
So
[tex]P(t) = P(0)(2.2361)^t[/tex]
(a) Find the initial population. P(0)
We have that P(2) = 400. We use this to find P(0). So
[tex]P(t) = P(0)(2.2361)^t[/tex]
[tex]400 = P(0)(2.2361)^2[/tex]
[tex]P(0) = \frac{400}{(2.2361)^2}[/tex]
[tex]P(0) = 80[/tex]
So
[tex]P(t) = 80(2.2361)^t[/tex]
(b) Find an expression for the population after t hours.
[tex]P(t) = 80(2.2361)^t[/tex]
(c) Find the number of cells after 7 hours.
This is P(7). So
[tex]P(7) = 80(2.2361)^7 = 22363[/tex]
22,363 cells.
(d) Find the rate of growth after 7 hours.
We have to find the derivative when t = 7. So
[tex]P(t) = 80(2.2361)^t[/tex]
[tex]P^{\prime}(t) = 80\ln{2.2361}(2.2361)^t[/tex]
[tex]P^{\prime}(7) = 80\ln{2.2361}(2.2361)^7 = 18000[/tex]
The rate of growth after 7 hours is of 18,000 bacteria per hour.
(e) When will the population reach 200,000?
This is t for which [tex]P(t) = 200000[/tex]. So
[tex]P(t) = 80(2.2361)^t[/tex]
[tex]200000 = 80(2.2361)^t[/tex]
[tex](2.2361)^t = \frac{200000}{80}[/tex]
[tex](2.2361)^t = 2500[/tex]
[tex]\log{(2.2361)^t} = \log{2500}[/tex]
[tex]t\log{2.2361} = \log{2500}[/tex]
[tex]t = \frac{\log{2500}}{\log{2.2361}}[/tex]
[tex]t = 9.7[/tex]
So 9.7 hours.
What is the surface area of a cylinder that has a radius of 7 m and a height of 18 m?
879.65 m2
1099.56 m2
615.75 m2
395.84 m2
1099.56m² is the surface area of a cylinder that has a radius of 7 m and a height of 18 m.
6 + 7* log base 2 of x = 21
6 + 7* log base 2 of x = 21
Answer:
Step-by-step explanation:
16: The temperature yesterday at noon was 68.5 degrees. Today at noon
it was 59.9 degrees. What was the difference in temperature?
O A. 8.4 degrees
OB. 8.5 degrees
C. 8.6 degrees
O D. 8.7 degrees
Answer:
C
Step-by-step explanation:
It is 8.6 because we are finding the difference and using subtraction.
So I did 68.8-59.9 and I got 8.6
Find the length of the missing side. If necessary, round to the nearest tenth.
A. 22
B. 15.6
C. 44
D. 484
Answer:
Option B, 15.6
Step-by-step explanation:
Using the Pythagoras theorem,
√(11²+11²)
= √(121+121)
= √(2×121)
= √121×√2
= 11√2
= 15.6
Answered by GAUTHMATH
Option B - 15.6 is Correct.
We have a figure in which a right angled triangle is shown with it base (b) = 11 and perpendicular(p) = 11.
We have to find the value of c or hypotenuse (h).
What is Pythagoras theorem?According to the Pythagoras theorem : for a right angled triangle -
[tex](h)^{2} = (b)^{2} +(p)^{2}[/tex]
According to the question -
[tex]b =11\\p =11\\h=c[/tex]
Substituting the values, we get -
[tex]c^{2} = (11)^{2} + (11)^{2} \\c^{2} = 121 + 121\\c^{2} =242\\c=15.55[/tex]
Rounding to nearest 10, we get -
c = 15.6
Hence , Option B is correct.
To solve more questions on Pythagoras theorem, visit the following link -
https://brainly.com/question/8587612
#SPJ2
If A={2,3,5,7} and B={2,4,6,8} then what is AnB?
Answer:
A∩B = {2}Step-by-step explanation:
It asks for the common set of A and B.
There only one element common to both the given sets:
A={2,3,5,7} and B={2,4,6,8} ⇒ A∩B = {2}Answer:
A ∩ B = {2}Step-by-step explanation:
∩ == this symbol stands for the common element/set
So according to this question you have to find the element which is common for both A and B sets.
A = { 2,3,5,7}B = {2,4,6,8}So now you can see that only number 2 is common for both.
So, the answer is,
A ∩ B = {2}What is the answer to 6,1=? 8,2=20, 12,3=20, 10,5=52, 6,1=?
can u plz check if the question is right
Women athletes at a certain university have a long-term graduation rate of 67%. Over the past several years, a random sample of 36 women athletes at the school showed that 23 eventually graduated. Does this indicate that the population proportion of women athletes who graduate from the university is now less than 67%? Use a 5% level of significance.
(a) What is the level of significance?
State the null and alternate hypotheses.
A. H0: p = 0.67; H1: p < 0.67
B. H0: p = 0.67; H1: p ≠ 0.67
C. H0: p < 0.67; H1: p = 0.67
D. H0: p = 0.67; H1: p > 0.67
(b) What sampling distribution will you use?
A. The standard normal, since np > 5 and nq > 5.
B. The standard normal, since np < 5 and nq < 5.
C. The Student's t, since np > 5 and nq > 5.
D. The Student's t, since np < 5 and nq < 5.
What is the value of the sample test statistic?
(c) Find the P-value of the test statistic. (Round your answer to four decimal places.)
Sketch the sampling distribution and show the area corresponding to the P-value.
(d) Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis? Are the data statistically significant at level α?
A. At the α = 0.05 level, we reject the null hypothesis and conclude the data are statistically significant.
B. At the α = 0.05 level, we reject the null hypothesis and conclude the data are not statistically significant.
C. At the α = 0.05 level, we fail to reject the null hypothesis and conclude the data are statistically significant.
D. At the α = 0.05 level, we fail to reject the null hypothesis and conclude the data are not statistically significant.
(e) Interpret your conclusion in the context of the application.
A. There is sufficient evidence at the 0.05 level to conclude that the true proportion of women athletes who graduate is less than 0.67.
B. There is insufficient evidence at the 0.05 level to conclude that the true proportion of women athletes who graduate is less than 0.67.
Answer:
A. H0: p = 0.67; H1: p < 0.67
A. The standard normal, since np > 5 and nq > 5.;
Test statistic = - 0.397 ;
Pvalue = 0.3457;
D. At the α = 0.05 level, we fail to reject the null hypothesis and conclude the data are not statistically significant.
B. There is insufficient evidence at the 0.05 level to conclude that the true proportion of women athletes who graduate is less than 0.67.
Step-by-step explanation:
p = 0.67 ; q = 1 - p = 1 - 0.67
Sample size, n = 36
x = 23
Test for normality :
(36*0.67) = 24.12
(36 * (1-0.67)) = 11.88
For a normal distribution :
np ≥ 5 and n(1 - p) ≥ 5
The hypothesis :
H0 : p = 0.67
H1 : p < 0.67
The Test statistic :
Z = (phat - p) / √[(p(1 -p))/n]
Phat = x / n = 23 / 36
Z = ((24/36) - 0.67)) / √[(0.67(1 -0.67))/36]
Z = - 0.031 / 0.0783687
Z = - 0.396983
Z = - 0.397
Usong the Pvalue from Z calculator ;
Pvalue of Z = 0.3457
If Pvalue < α ; Reject H0 ; If otherwise, Fail to reject H0
What is x: |3x-1| = 4
Step-by-step explanation:
3x-1=4
3x=4+1
3x=5
x=5/3
Answer:
x = 5/3 x = -1
Step-by-step explanation:
|3x-1| = 4
There are two solutions, one positive and one negative
3x-1 =4 and 3x-1 = -4
Add 1 to each side
3x-1+1 = 4+1 3x-1+1 = -4+1
3x = 5 3x = -3
Divide by 3
3x/3 = 5/3 3x/3 = -3/3
x = 5/3 x = -1
Samuel had 12 red marbles , 15 blue marbles , and 13 green marbles . Which fraction represents the number of red marbles he has
Answer:
12/40 or simplified it would be 3/10
Step-by-step explanation:
What is the area of my lawn if it measures 4m x 4.5m
Answer:
18m squared
Step-by-step explanation:
4m x 4.5m = ?
What are the coordinates of point K?
A (-2,4)
B (-2,-4)
C (2,-4)
D (2, 4)
Answer:
A
Step-by-step explanation:
I guess that is the answer
A semi-circle sits on top of a rectangle to form the figure below. Find its area and perimeter. Use 3.14 for .
4 in.
6 in.
O A = 38.13 square inches, P = 32.84 inches
O A = 80.52 square inches, P = 32.84 inches
O A = 38.13 square inches, P = 23.42 inches
O A = 80.52 square inches, P = 23.42 inches
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Answer:
(c) A = 38.13 square inches; P = 23.42 inches
Step-by-step explanation:
The radius of the circle is half the diameter, so is 3 inches. This means the entire figure will fit in a rectangle 6 inches wide and 4+3 = 7 inches high. The perimeter of such a rectangle is ...
P = 2(L+W) = 2(7+6) = 26 inches
The area of that rectangle is ...
A = LW = (7)(6) = 42 square inches
Then area of the given figure is less than 42 square inches, and the perimeter is less than 26 inches. The only answer choice that matches these bounds is ...
A = 38.13 square inches; P = 23.42 inches
Bianca is planting trees along her driveway, and she has 55 sycamores and 55 palm trees to plant in one row. What is the probability that she randomly plants the trees so that all 55 sycamores are next to each other and all 55 palm trees are next to each other
Answer:
0.0079 = 0.79% probability that she randomly plants the trees so that all 5 sycamores are next to each other and all 5 palm trees are next to each other.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
The trees are arranged, so, to find the number of outcomes, the arrangements formula is used.
Arrangements formula:
The number of possible arrangements of n elements is given by:
[tex]A_n = n![/tex]
Desired outcomes:
5 sycamores(5! possible ways) and then the 5 palm trees(5! possible ways)
5 palm trees(5! possible ways) then the 5 sycamores(5! possible ways).
[tex]D = 2*5!*5![/tex]
Total outcomes:
Arrangements of 10 plants, so:
[tex]T = 10![/tex]
What is the probability that she randomly plants the trees so that all 5 sycamores are next to each other and all 5 palm trees are next to each other?
[tex]p = \frac{D}{T} = \frac{2*5!*5!}{10!} = 0.0079[/tex]
0.0079 = 0.79% probability that she randomly plants the trees so that all 5 sycamores are next to each other and all 5 palm trees are next to each other.
Find the APR, rounded to the nearest tenth of a percent (one decimal place) for the loan. Purchase a living room set for $4,900 at 8% add-on interest for 4 years. Enter only the number without % sign.
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Answer:
14.3%
Step-by-step explanation:
We assume this question is asking for the annual interest rate for an amortized loan that would produce the same total repayment amount as if 8% simple interest were added to the $4900 loan amount. There is no formula for that, but there are a number of apps and spreadsheets that can calculate it. In the attached, we have use a graphing calculator.
The APR is about 14.3%.
_____
The amount to be repaid is calculated using the simple interest formula:
A = P(1 +rt) = $4900(1 +0.08·4) = $6468
Then the required monthly payment (for 48 months) is ...
$6468/48 = $134.75
__
The payment amount for a 48-payment loan at rate r on a principal of $4900 will be ...
A = 4900(r/12)/(1 -(1 +r/12)^-48)
In the attachment, we show the value of r (in percent) that would make the payment amount A be $134.75. We have done this by casting the problem in the form f(r) = 0 and looking for the x-intercept of f(r).
_____
Additional comment
The second attachment uses a spreadsheet for the same purpose. Here, we have used Go.ogle Sheets with a "Goal Seek" add-on to adjust the value in cell B5 so that the computed payment on the loan (cell B6) is the same as the value we calculated in cell B4.
We found the graphing calculator solution to be much quicker, though in that case we actually had to know the formula to use to calculate the payment. The payment formula is built into the spreadsheet.
If you wanted to make a game where you pay $5 if you can't guess a random dogs weight within 16lbs what payout should you offer you make the game zero-expected value
Answer:
Following are the solution to the given question:
Step-by-step explanation:
The population std. dev of the dog weight=8
[tex]\sigma=8\\\\P(\text{guess with in 16 lbs}) = P(|X-\mu|\leq 16)\\\\=P(-2 \leq Z \leq 2) = 0.9544\\\\[/tex]
Calculating the payout w s.t:
[tex]E[netpay]=0=(-5) \times 0.9544+w\times (1-0.9544)\\\\ w =(5 \times \frac{0.9544}{1-0.9544}) =\$ 104.65[/tex]
therefore, we assume that the weight of the dog is a normal distribution with std. deviation that is 8.
Which graph is a function?
Answer:
B
Step-by-step explanation:
A function is a relation in which each input, x, has only one output, y.
There are two ways to determine if a relation is a function:
1. If each x-input has only one, unique y-output, then it's a function. If some x-inputs share the same y-outputs, it's not a function.
2. Vertical Line Test on Graphs:
To determine whether y is a function of x, when given a graph of relation, use the following criterion: if every vertical line you can draw goes though only 1 point, the relation can be a function. If you can draw a vertical line that goes though more than 1 point, the relation cannot be a function.
Since we're given a graph relation, let's test both of the answers out.
If I were to draw a vertical line in a specific place on the first graph, I'd be hitting more than one point in the coordinate plane.
If I were to draw a vertical line in a specific place on the second graph, I'd only be hitting one point in the coordinate plane.
Therefore, choice B is a function.
You plan to charge $1 for each time a student plays, and the payout for a win is $5. According to your calculations, the probability of a win is .05. What is your expected value for this game? The expected value
Answer:
- $0.75Step-by-step explanation:
For each game played the chance of winning is 0.05 and losing is 0.95.
If the student wins, they get $5 -$1 = $4, but they lose $1.
Expected value is:
4*0.05 - 1*0.95 = -0.75It means you will make $0.75 per average game.
Answer:
21.8
Step-by-step explanation:
Step 1
This is a problem on finding the mean of continuous grouped data. We first find the midpoint of each interval. For example, the first interval or class is 0 - 10. The mid-point of this class will be (0 + 10)/2 = 5.
fullscreen
Step 2
We now calculate the product of mid-point and frequency for each class. Here, the number of athletes in each class is the frequency of that class. For example, for the first class 0 – 10, its frequency is 3.
fullscreen
Step 3
We can now use the formula to calculate mean. Note that t...
If y = sin 3x, find y" in terms of y.
Answer:
-0.54
Step-by-step explanation:
Hope it helped.
• • •
Jake has corn growing on 66 2/3% of his 330 acres. How many acres are being used for corn?
on 220 acres
66 ⅔% is just ⅔ of 100%
330 * 2 / 3 = 220
Please help me with this question
Find the difference between each number:
-11 to -3 is +8
-3 to 5 is +8
The difference is 8
Use the following formula:
Bn = b1 + d(b -1)
Answer: bn = -11 + 8( b-1)
What is the volume of the
cylinder? Use 3.14 for a.
A 1200 cubic inches
B 1884 cubic inches
C 3768 cubic inches
D 28,260 cubic inches
Answer:
Step-by-step explanation:
area of top face = π15² = 225π in²
volume = 225π × 40 = 9000π ≅28,260 in³
visually demonstrate the following value using the hundred square below
Answer:
just fill in 40 squres
Step-by-step explanation:
A decreasing inventory turnover ratio indicates:_______
a. a longer time span between the purchase and sale of inventory.
b. a shorter time span between the purchase and sale of inventory.
c. a longer time span between the ordering and receiving of inventory.
d. a shorter time span between the ordering and receiving of inventory.
what represent the relationship between the total mass of a crate
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Answer:
(a) M = 0.25n +100
Step-by-step explanation:
The distance between the dots on the graph is a rise of 1 grid square and a run of 2 grid squares. If we extend the sequence of dots to the left, we expect to place one at (0, 100). That is, the y-intercept of this function is 100 (eliminates choices C and D).
The rise of 1 grid square represents 25 kg, and the run of 2 grid squares represents 100 CDs. Then the slope of the function (rate of change) is ...
slope = rise/run = 25/100 kg/CD = 0.25
Then the equation describing the points on the graph will be ...
M = 0.25n +100
a. 1140
b. 1130
c. 1120
d. 115
Answer:
1130
Step-by-step explanation:
1109+7 = 1116
1116+7 = 1123
Adding 7 each time
1123+7 = 1130
Calculate the range and the standard deviation for the set of numbers.
6,5, 1, 5, 8, 5, 3, 5, 4,7
The range is
(Simplify your answer.)
Can I please get help with this problem?
Answer:
When time is short and you just want a rough estimate of the standard deviation, turn to the range rule to quickly estimate the standard deviation value. The standard deviation is approximately equal to the range of the data divided by 4. That's it, simple.
A line has a slope of 11 and passes through the point (5,7). Which of these is an equation for the line? O A. y-7 = -11(x - 5) B. y + 7 = 11(x + 5) O C. y-5 = -11(x - 7) O D. y - 7 = 11(x - 5) SUBMIT
Answer:
D. y - 7 = 11(x - 5)
Step-by-step explanation:
Use point slope form, y - y1 = m(x - x1), where m is the slope and (x1, y1) is a point on the line.
Plug in the given slope and point:
y - y1 = m(x - x1)
y - 7 = 11(x - 5)
So, the correct answer is D. y - 7 = 11(x - 5)
Một miếng đất hình chữ nhật có chu vi 80 mét.Nếu kéo dài thêm 8 mét nữa thì diện tích tăng thêm là 72 mét vuông.Tính chiều dài và chiều rộng hình chữ nhật ban đầu ?
Answer:
Step-by-step explanation:
(D+R) = 80:2 = 40
D = 40-R
(D+8) * R = 72X
Thay D=40-R
(40-R+8)*R = 72X
R=1.55, D=38.45
