A recent article in a university newspaper claimed that the proportion of students who commute more than miles to school is no more than . Suppose that we suspect otherwise and carry out a hypothesis test. State the null hypothesis and the alternative hypothesis that we would use for this test.
Answer:
The null hypothesis is [tex]H_0: p \leq x[/tex], in which x is the proportion tested.
The alternative hypothesis is [tex]H_1: p > x[/tex]
Step-by-step explanation:
A recent article in a university newspaper claimed that the proportion of students who commute more than miles to school is no more than x.
This means that at the null hypothesis, we test if the proportion is of at most x, that is:
[tex]H_0: p \leq x[/tex]
Suppose that we suspect otherwise and carry out a hypothesis test.
The opposite of at most x is more than x, so the alternative hypothesis is:
[tex]H_1: p > x[/tex]
The radioactive isotope carbon-14 is present in small quantities in all life forms, and it is constantly replenished until the organism dies, after which it decays to stable carbon-12 at a rate proportional to the amount of carbon-14 present, with a half-life of 5549 years. Let C(t) be the amount of carbon-14 present at time t.
(a) Find the value of the constant k in the differential equation C' = -kC.
(b) In 1988 three teams of scientists found that the Shroud of Turin, which was reputed to be the burial cloth of Jesus, contained 91% of the amount of carbon-14 contained in freshly made cloth of the same material. How old was the Shroud of Turin at the time of this data?
Answer:
a) k = 0.00012491389
b) The Shroud of Turin was 755 years old at the time of this data.
Step-by-step explanation:
(a) Find the value of the constant k in the differential equation C' = -kC.
First we find the differential equation, by separation of variables. So
[tex]\int \frac{C^{\prime}}{C} dt = -\int k dt[/tex]
So
[tex]\ln{C} = -kt + K[/tex]
In which K is the constant of integration, representing the initial amount of substance. So
[tex]C(t) = C(0)e^{-kt}[/tex]
Half-life of 5549 years.
This means that [tex]C(5549) = 0.5C(0)[/tex]. We use this to find k. So
[tex]C(t) = C(0)e^{-kt}[/tex]
[tex]0.5C(0) = C(0)e^{-5549k}[/tex]
[tex]e^{-5549k} = 0.5[/tex]
[tex]\ln{e^{-5549k}} = \ln{0.5}[/tex]
[tex]-5549k = \ln{0.5}[/tex]
[tex]k = -\frac{\ln{0.5}}{5549}[/tex]
[tex]k = 0.00012491389[/tex]
So
[tex]C(t) = C(0)e^{-0.00012491389t}[/tex]
(b) In 1988 three teams of scientists found that the Shroud of Turin, which was reputed to be the burial cloth of Jesus, contained 91% of the amount of carbon-14 contained in freshly made cloth of the same material. How old was the Shroud of Turin at the time of this data?
This is t for which [tex]C(t) = 0.91C(0)[/tex]
So
[tex]C(t) = C(0)e^{-0.00012491389t}[/tex]
[tex]0.91C(0) = C(0)e^{-0.00012491389t}[/tex]
[tex]e^{-0.00012491389t} = 0.91[/tex]
[tex]\ln{e^{-0.00012491389t}} = \ln{0.91}[/tex]
[tex]-0.00012491389t = \ln{0.91}[/tex]
[tex]t = -\frac{\ln{0.91}}{0.00012491389}[/tex]
[tex]t = 755[/tex]
The Shroud of Turin was 755 years old at the time of this data.
Translate the following into an algebraic expression: If it would take Mark m hours to clean the house alone and with his brother Sam they can clean the house together in t hours. How many hours would it have taken Sam if he was working alone
An important factor in selling a residential property is the number of times real estate agents show a home. A sample of 15 homes recently sold in the Buffalo, New York, area revealed the mean number of times a home was shown was 24 and the standard deviation of the sample was 5 people.
a. What is the margin of error for a 98% confidence interval? (Round your answer to 3 decimal places.)
b. What is the 98% confidence interval for the population mean? (Use Student's t Distribution Table.) (Round your answers to 2 decimal places.)
Answer:
a) The margin of error for a 98% confidence interval is of 3.388 people.
b) The 98% confidence interval for the population mean is between 20.61 people and 27.39 people.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the hypergeometric distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 15 - 1 = 14
98% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 14 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.98}{2} = 0.99[/tex]. So we have T = 2.624
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 2.624\frac{5}{\sqrt{15}} = 3.388[/tex]
In which s is the standard deviation of the sample and n is the size of the sample. This means that the answer to question a is of 3.388.
Question b:
The lower end of the interval is the sample mean subtracted by M. So it is 24 - 3.39 = 20.61 people
The upper end of the interval is the sample mean added to M. So it is 24 + 3.39 = 27.39 people.
The 98% confidence interval for the population mean is between 20.61 people and 27.39 people.
what is the formula for triangle
Answer:
BH/2
Step-by-step explanation:
For the area of the triangle, (BH)/2. B=base and H=height
Luke makes fruit cakes for a stall at a village fete. It costs Luke £1.80 for
the ingredients for each cake. If he wants to make exactly 35% profit on
each cake, how much money should Luke charge for each cake?
Answer:
2.43
Step-by-step explanation:
1.80 x 0.35 + 1.80
A field book is a private notepad used by a surveyor to transcribe notes and is not considered a legal document True False
Answer:
False
Step-by-step explanation:
A field book is a private notepad used by a surveyor to record measurements and notes.
Basically, the size of a field book is 200 millimeters × 120 millimeters (20 centimeters × 12 centimeters) and it's typically opened lengthwise. There are two (2) main types of field book and these includes;
I. Double-line field book.
II. Single-line field book.
As a general rule, it's best that all findings, entries (notes) and observations are recorded or made into a field book after each and every measurement have been taken by a surveyor.
In conclusion, a field book is considered to be a legal document used by surveyors to keep records of accomplished field work or work done in the field. Thus, it's not a private notepad used by a surveyor to transcribe notes.
Answer:
False
Step-by-step explanation:
A field book is a private notepad used by a surveyor to transcribe notes and is not considered a legal document is False.
The functions f (x) = 1/2x-3 and g(x) = -2x+ 2 intersect
at x = -2. True or false?
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Answer:
False
Step-by-step explanation:
f(-2) = (1/2)(-2) -3 = -1 -3 = -4
g(-2) = -2(-2) +2 = 4 +2 = 6
The function values are not the same at x=-2, so the graphs do not intersect there.
__
The graphs intersect at x=2.
Mathematics I need help
Answer:A
Step-by-step explanation:
When studying radioactive material, a nuclear engineer found that over 365 days,
1,000,000 radioactive atoms decayed to 970,258 radioactive atoms, so 29,742 atoms
decayed during 365 days.
a. Find the mean number of radioactive atoms that decayed in a day.
b. Find the probability that on a given day, 50 radioactive atoms decayed.
a. The mean number of radioactive atoms that decay per day is
(Round to three decimal places as needed.)
Answer:
a) The mean number of radioactive atoms that decay per day is 81.485.
b) 0% probability that on a given day, 50 radioactive atoms decayed.
Step-by-step explanation:
Poisson distribution:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\lambda}*\lambda^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
e = 2.71828 is the Euler number
[tex]\lambda[/tex] is the mean in the given interval.
a. Find the mean number of radioactive atoms that decayed in a day.
29,742 atoms decayed during 365 days, which means that:
[tex]\lambda = \frac{29742}{365} = 81.485[/tex]
The mean number of radioactive atoms that decay per day is 81.485.
b. Find the probability that on a given day, 50 radioactive atoms decayed.
This is P(X = 50). So
[tex]P(X = 50) = \frac{e^{-81.485}*(81.485)^{50}}{(50)!} = 0[/tex]
0% probability that on a given day, 50 radioactive atoms decayed.
Sticky buns sell for $1.25 each,or $10.89 per dozen. how much does each bun cost if purchased by the dozen? How much do you save on 12 sticky buns?
Answer:
If you buy per dozen, each buns costs about 91 cents.
You will save $4.11 if you buy per dozen.
Step-by-step explanation:
1.25 * 12= $15
10.89/12= .9075 = .91 cents
15-10.89= $4.11
Kayo earns a weekly salary of $372 at All Sports, Next month, she will be promoted from assistant buyer to head buyer. In her new position, she will be paid $831.33
semimonthly. How much more per year will Kayo earn as a head buyer than as assistant buyer?
Answer:
ok so if she gets paid 372 we just multiply this by 4 since there's 4 weeks in a month then we multiply by 4 so
372*4*12=17856
now we just multiply 831.33 by 2 since she is paid semimonthly and we multiply by 12
831.33*2*12=19951.92
now we just subtract
19951.92-17856=2095.92
so she gets paid 2095.92 more dollars per year
Hope This Helps!!!
A particular network service provider charges 50 Kobo per second to make a call. How many minutes will a caller with 300 naira airtime last.
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Answer:
10 minutes
Step-by-step explanation:
The current legal tender conversion rate is 50 kobo = 0.50 naira. Then the airtime balance is ...
(300 NGN)/(0.50 NGN/s) × (1 min)/(60 s) = 300/(0.50×60) min = 10 min
3z+8=12+3x-z
I need help someone help me
Answer:
z=3x/4+1 x=4z/3-4/3
Step-by-step explanation:
PLEASE HELP
The function in the table is quadratic
True
False
Answer:
True
Step-by-step explanation:
Each f(x) value increases by 5 so therefore this function would be linear
Hope you understand :)
²/₃ + ¹/₃ please answer
FINAL ANSWER:
1
Step-by-step explanation:
[tex]\frac{2}{3} +\frac{1}{3}[/tex]
the denominators are the same so all we need to do is add.
[tex]\frac{2}{3} + \frac{1}{3} =\frac{3}{3}[/tex]
[tex]\frac{3}{3} =[/tex] 1 whole
final answer: 1
hope this answer helps you :)
have a great day and may God Bless You!
Question
The sum of three consecutive even integers is -312. Find the Integers.
Answer:
-105, -104, -103
Step-by-step explanation:
lets the numbers be:
x
x+1
x+2
so:
x+(x+1)+(x+2)=-312
x+x+x+1+2=-312
3x+3=-312
3x=-312-3=-315
x=-315/3=-105
Need help with this one please
it right answer is Clovis 2.5% it answer
There are 3 boxes on stage that appear identical, but one is Lucky. The boxes are full of tickets; some are labeled "win" and the others are labeled "lose." In the Lucky box, ninety percent of the tickets are winners. In each of the other two boxes, only twelve percent of the tickets are winners.
1. You will pick a box at random and draw one ticket from it at random.2. What is the probability you will draw a winning ticket? 3. If you do draw a winning ticket, what is the chance it came from the Lucky box?
Answer:
2.-P = 0.38
3.-P [ Lb | Wt ] = 0.788
Step-by-step explanation:
1.-Probability of choosing any box is, 1/3. So the probability of choosing the lucky box is 1/3
Let´s say the lucky box is the number 2 box ( that consideration does not in any way change the problem generality)
Then we have
p₁ probability of choosing box 1 is 1/3 p₁´ Probability of win ticket is 0.12
p₂ probability of choosing box 2 is 1/3 p₂´Probability of win ticket is 0.90
p₃ probability of choosing box 3 is 1/3 p₃´ Probability of win ticket is 0.12
Then
P (of choosing a winning ticket is) = p₁*p₁´ + p₂*p₂´ + p₃*p₃´
P = 1/3*0.12 + 1/3*0.9 + 1/3*0.12
P = 0.04 + 0.3 + 0.04
P = 0.38
3.- if I draw a winning ticket what is the probability it came from Lucky box
According to Bayes theorem
P [ Lb | Wt ] = P(Lb) * P[ Wt|Lb]/ P(Wt)
P(Lb) = 1/3 = 0.33333
P[Wt|Lb] = 0.9
P(Wt) = 0.38
Then By substitution
P [ Lb | Wt ] = 0.333 * 0.9 / 0.38
P [ Lb | Wt ] = 0.788
A study of the pay of corporate chief executive officers (CEOs) examined the increase in cash compensation of the CEOs of 104 companies, adjusted for inflation, in a recent year. The mean increase in real compensation was x¯=6.9%, and the standard deviation of the increases was s=55%. Is this good evidence that the mean real compensation μ of all CEOs increased that year? The hypotheses are
Answer:
The p-value of the test is 0.1017, which is greater than the standard significance level of 0.05, which means that this is not good evidence that the mean real compensation μ of all CEOs increased that year.
Step-by-step explanation:
At the null hypothesis, we test if there was no increase, that is, the mean is 0, so:
[tex]H_0: \mu = 0[/tex]
At the alternative hypothesis, we test if there was an increase, that is, the mean is greater than 0, so:
[tex]H_1: \mu > 0[/tex]
The test statistic is:
[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, s is the standard deviation and n is the size of the sample.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
104 companies, adjusted for inflation, in a recent year. The mean increase in real compensation was x¯=6.9%, and the standard deviation of the increases was s=55%.
This means that [tex]n = 104, X = 6.9, s = 55[/tex]
Value of the test-statistic:
[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]
[tex]t = \frac{6.9 - 0}{\frac{55}{\sqrt{104}}}[/tex]
[tex]t = 1.28[/tex]
P-value of the test:
The p-value of the test is a right-tailed test(test if the mean is greater than a value), with 104 - 1 = 103 df and t = 1.28.
Using a t-distribution calculator, this p-value is of 0.1017.
The p-value of the test is 0.1017, which is greater than the standard significance level of 0.05, which means that this is not good evidence that the mean real compensation μ of all CEOs increased that year.
Why is the number of operators per shift multiplied by approximately 4.5 to obtain the total number of operators required to run the plant
I believe you meant "why is the number of shifts multiplied by approximately 4.5 to obtain the total number of operators required to run the plant"
Answer and Explanation:
There are 3 shifts per day, 49 weeks per year and 5 shifts per operator per week
To get total number of operators required to run the plant, we multiply number of shifts in a year by number if operators per shift.
49 weeks×5 shifts= 245 shifts per operator per year
365×3 shifts= 1095 shifts per year
1095/245=4.5 operators per shift
total number of operators required to run the plant(per day) = 4.5×3= 13.5 approximately 14
total number of operators required to run the plant(per year) =4.5×1095=4927.5 approximately 4928
What is the area of the trapezoid?
176 cm2
192 cm2
208 cm2
224 cm2
Answer:A. This is the formula for the area of a trapezoid: a+b/2 x height (a and b being the bases)
Step-by-step explanation: Use the formula. 10+12=22. 22/2 is 11. 11 x 16 is 176. Therefore, the answer is A.
math help plz
how to divide polynominals, how to understand and step by step with an example provided please
Answer:
I guess this is the answer hope it helps
please help! i need this ASAP!
Answer:
C. y=7/9x+17/9
Step-by-step explanation:
Take the slope. slope= m = y2-y1/x2-x1
=5-(-2)/4-(-5)
=7/9
Then put it into point-slope form.
y-y1=m(x-x1)
=y-5=7/9(x-4)
Simplify.
y=7/9x-28/9+5
y=7/9x+17/9
Answer:
C
Step-by-step explanation:
First find the slope (change in y/ change in x) which is positive 7/9.
Then use y=mx+b and plug in the slope, and one of the given points to solve for b.
5= 7/9*4+b
5=28/9+b
5-28/9=b
45/9-28/9=b
17/9=b
Then with the slope and y intercept(b) you get the equation shown in answer c.
Hope that helps!
What is the value of the expression [-7] + [-4]
Answer:
11
Step-by-step explanation:
I'm assuming that [.] fldenote absolute value even tho the absolute value function is represented by (|.|)
value of [-7] will be positive that us 7.
= 7 + 4
= 11
ASK YOUR TEACHER A 12-sided die can be made from a geometric solid called dodecahedron. Assume that a fair dodecahedron is rolled. (a) What is the probability of getting a number less than 10 on a single roll
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Answer:
3/4
Step-by-step explanation:
Assuming the faces are numbered 1 to 12, there are 9 faces with values less than 10. Since the outcomes are equally probable and mutually exclusive, the probability of any of the 9 is the sum of their individual probabilities:
P(n < 10) = 9×1/12 = 9/12 = 3/4
What is 12 x 12 ?
A. 12
b. 144
c. 147
d. 2574
Answer:
b
Step-by-step explanation:
I need help on this. Please someone help. I would appreciate it!
Use the circular formula and divide the volume by 2
Step-by-step explanation:
Answer:
12.56
Step-by-step explanation:
3.14(8)/2
=12.56
Round 790 to the nearest hundred? Hurry pls and please don't answer if you know you wrong
Answer:
HEY THERE!
Step-by-step explanation:
the answer is:800
hope it helps and have a great day!
Ans: 800
explanation:
20. In the image, ABC has measure 58°. What is the measure of ABD?
A. 116°
OB. 29°
O C. 58
OD. There is not enough information to determine LABD.
Answer:
Option B, 29°
Step-by-step explanation:
The diagram is a angle bisecting diagram which divides the 58° angle into two 29° angles.
Answered by GAUTHMATH
