It has been observed that some persons who suffer acute heartburn, again suffer acute heartburn within one year of the first episode. This is due, in part, to damage from the first episode. The performance of a new drug designed to prevent a second episode is to be tested for its effectiveness in preventing a second episode. In order to do this two groups of people suffering a first episode are selected. There are 163 people in the first group and this group will be administered the new drug. There are 160 people in the second group and this group wil be administered a placebo. After one year, 13% of the first group has a second episode and 14% of the second group has a second episode. Select a 90% confidence interval for the difference in true proportion of the two groups.
a) [0.00590, 0.0251].
b) [0.00690, 0.0551].
c) [0.0890, 0.0551].
d) [0.00690, 0.0351].
e) [0.00890, 0.0651].
Answer:
90% confidence interval for the difference in true proportion of the two groups is (-0.0717, 0.0517).
Step-by-step explanation:
Before building the confidence interval, 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 between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
First group: Sample of 163, 13% has a second episode.
This means that:
[tex]p_1 = 0.13, s_1 = \sqrt{\frac{0.13*0.87}{163}} = 0.026[/tex]
Second group: Sample of 160, 14% has a second episode
This means that:
[tex]p_2 = 0.14, s_2 = \sqrt{\frac{0.14*0.86}{160}} = 0.027[/tex]
Distribution of the difference:
[tex]p = p_1 - p_2 = 0.13 - 0.14 = -0.01[/tex]
[tex]s = \sqrt{s_1^2+s_2^2} = \sqrt{0.026^2+0.027^2} = 0.0375[/tex]
Confidence interval:
The confidence interval is:
[tex]p \pm zs[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
90% confidence level
So [tex]\alpha = 0.1[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].
Lower bound:
[tex]p - 1.645s = -0.01 - 1.645*0.0375 = -0.0717[/tex]
Upper bound:
[tex]p + 1.645s = -0.01 + 1.645*0.0375 = 0.0517[/tex]
90% confidence interval for the difference in true proportion of the two groups is (-0.0717, 0.0517).
sin 0 =(8)/(9), tan 0 >0
find sec 0
Answer:
[tex]\displaystyle \sec(\theta)=\frac{9\sqrt{17}}{17}[/tex]
Step-by-step explanation:
We are given that:
[tex]\displaystyle \sin(\theta)=\frac{8}{9}\text{ and } \tan(\theta)>0[/tex]
And we want to find sec(θ).
First, note that both sine and tangent are positive. The only quadrant in which this can occur is QI. Hence, all trig ratios will be positive.
Also, recall that sine is the ratio of the opposite side to the hypotenuse. Using this information and the Pythagorean Theorem, we can determine the adjacent side:
[tex]a=\sqrt{9^2-8^2}=\sqrt{17}[/tex]
So, with respect to θ, the adjacent side is √(17), the opposite side is 8, and the hypotenuse is 9.
Secant is the ratio of the hypotenuse to the adjacent. Hence:
[tex]\displaystyle \sec(\theta)=\frac{9}{\sqrt{17}}=\frac{9\sqrt{17}}{17}[/tex]
Again, since θ is in QI, all trig ratios are positive.
10x -5 = 15
O X = 10
X =-1
x = 2
O X= -2
Answer:
0
Step-by-step explanation:
Anything multiplied by 0 is 0. sorry if i did it wrong
PLEASE HELP I DONT KNOW
Answer:
the answer is d circumference
HELP PLZ! WILL GIVE BRAINLIEST.
The table shows the percentage of users of a data tablet who returned the product to an Internet provider within a year after purchase, after a year, and the reasons for the return.
Answer:
ur answer is correct only
Step-by-step explanation:
mark me brainlist tq
Answer:
dependent events
is 2 a solution to the equation 1/2 x 4 = 5 ?
Answer:
yes it is good luck with your work
−
7
<
−
1
2 i really need help plz
Answer:
I'm guessing you mean -7 < -12 and if it's true and false, if so the answer would be false because -7 is larger than -12.
Step-by-step explanation:
I'm guessing you mean -7 < -12 and if it's true and false, if so the answer would be false because -7 is larger than -12.
(Tell me the question if this is incorrect. Thanks!!!)
Can I have brainliest? It would help me out, if not thanks anyways! Hope this helped and have a nice day!
x2 - 49 = 0 solve in factored form
Answer:
x = -7 or 7
Step-by-step explanation:
x² - 49 = 0
→ Factorise
( x + 7 ) ( x - 7 )
→ Solve
x = -7 or 7
Answer:
(x + 7) (x - 7) = 0
x + 7 = 0 and x - 7 = 0
So, x = +7 and -7
Hope this helps!
Can someone help me with this part A: Members of a high school sports team are selling two popular items for a fundraiser:
candy bars and bags of chips. They earn $0.75 for every candy bar they sell and $0.50 for every
Dag of chips. The members want to earn at least $100 from all sales. The members of the sport
team estimate that they won't be able to sell more than 200 units in total.
Part A: Select all the inequalities that model the constraints for this situation, where x
represent the number of candy bars sold and y represent the number of bags of chips.
A. x 20
B. y20
C. x +y s 100
D. x + y < 200
E. 0.75x + 0.50y
100
F. 0.50x + 0.75y > 100
An
Step-by-step explanation:
Cx+y s 100
Answer:
All the inequalities that model the constraints for this situation:
(d) x + y < 200 ;
(e) 0.75 x + 0.50 y ≥ 100
Step-by-step explanation:
What is inequality ?A statement of an order relationship—greater than, greater than or equal to, less than, or less than or equal to—between two numbers or algebraic expressions.
As, x represent the number of candy bars sold & y represent the number of bags of chips sold.
It is given that,
price for one candy bar = $0.75
also, price for one dag of chips = $0.50
So, price for 'x' candy bar = $0.75x
also, price for 'y' of chips = $0.50 y
Is is mentioned in question, the sale of candy bar and bag of chips shoud be atleast $100.
the First ineqaulity be,
0.75 x + 0.50 y ≥100
(which should the sales of candy baar and dag of chips be equal to 100 dollar or greater than 100 dollar)
Now, the second situation
Again, it is mentioned in the question is number of units (candy bar and dag of chips) should be not more than 200 units.
the second inequality be,
x+ y < 200
(which shows that number of candy bar and dag of chips should be less than 200 units.)
All the inequalities that model the constraints for this situation
(d) x + y < 200
(e) 0.75 x + 0.50 y ≥100
Learn more about inequalities here:
https://brainly.com/question/20383699
#SPJ2
Shari bought 3 breath mints and received $2.76 change.Jamal bought 5 breath mints and received $1.20 change. If Shari and Jamal had the same amount of money how much does each breath mint cost?
Answer:
Step-by-step explanation:
Is anyone good at geometry if so can someone help me please ?
NO LINKS PLEASE
Answer: 9
Step-by-step explanation: h=2(A/a+b)=2(66.66/4.9+9.9)=9.01
What is the greatest common factor of 12 and 20?
OA) 2
O B) 3
4
D) 6
Answer:
4
Step-by-step explanation:
You can divide both numbers by four and get an even answer
Answer:
4
Step-by-step explanation:
what is the measure of m
9514 1404 393
Answer:
m = 8
n = 4√3
Step-by-step explanation:
The right triangles in this figure are all similar, so the ratios of hypotenuse to short side are the same.
(12+4)/m = m/4
64 = m² . . . . multiply by 4m
8 = m . . . . . . square root
__
Likewise, the ratio of long side to short side is the same.
12/n = n/4
48 = n² . . . . . . multiply by 4n
4√3 = n . . . . . take the square root
_____
Additional comment
You may have noticed that the ratios of side lengths are ...
4 : n : m = 4 : 4√3 : 8 = 1 : √3 : 2 . . . . . side lengths of a 30°-60°-90° triangle
This means the unmarked side is 8√3.
__
We supplied all of the missing lengths because we know this problem is likely to be presented in different forms, asking for values other than m.
What is the domain?
A
B
C
D
Answer:
C
Step-by-step explanation:
1. The domain is the x-value of a function.
2. In that image, the x-values are the numbers on the left of each parenthesis.
3. You should put the domains in increasing order, so the final answer is -2, 0, 2, 4.
Grandma decides to pay for her new granddaughter's education. She gives
her one penny on her first birthday, and doubles the gift every year. Round
to the nearest hundredth. Do not use a dollar sign, numerical values only.
What will be the total of all the gifts on the girl's 18th birthday?
Answer:
Around 0.40
Step-by-step explanation
If she doubles the gift every year, do 18x2=36, 36 rounds to 40 or 0.40.
The total of all the gifts on the girl's 18th birthday given from her grandma for this considered case is evaluated as 2621.43 dollars
What is the sum of the terms of a geometric series till nth term?Lets suppose the geometric sequence has its initial term is [tex]a[/tex], multiplication factor is r, then, its sum is given as:
[tex]S_n = \dfrac{a(r^n-1)}{r-1}[/tex]
(sum till nth term)
The sequence would look like [tex]a, ar, \cdots, ar^{n-1},\cdots[/tex]
For this case, we are specified that:
Grandma gives 1 penny on first birthday of her granddaughterGrandma increases the gift by doubling the previous birthday gift.That shows that the gift amounts each year will form a geometric sequence where a = 1, and r = 2 (as amounts are doubled).
The gift amounts would look like:
[tex]\\1, 2, 4, \cdots\\or\\1, 2\times 1, 2^2 \times 1, \cdots[/tex]
We have to find these terms' sum till 18th term(18th term is the gift of her 18th birthday).
Thus, we have: n = 18, a = 1, and r = 2.
The sum will be:
[tex]S_n = \dfrac{a(r^n-1)}{r-1} = \dfrac{1(2^{18}-1)}{2-1} = 2^{18} - 1 = 262143 \: \rm cents[/tex]
There are 100 cents in 1 dollars,
Thus, 1 cent = 0.01 dollars,
and thus, 262143 cents form 2621.43 dollars.
Thus, the total of all the gifts on the girl's 18th birthday given from her grandma for this considered case is evaluated as 2621.43 dollars
Learn more about sum of terms of geometric sequence here:
https://brainly.com/question/1607203
Two fair 6-sided dice are rolled one at a time. Find the probability that
the first die lands on a value greater than 4 and the second die lands
on 2.
Answer:
Step-by-step explanation:
The lengths of adult males' hands are normally distributed with mean 187 mm and standard deviation is 7.1 mm. Suppose that 12 individuals are randomly chosen. Round all answers to 4 where possible. What is the distribution of ¯ x
Answer:
By the Central Limit Theorem, the distribution of ¯ x is approximately normal with mean 187 and standard deviation 2.05.
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem establishes 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.
The lengths of adult males' hands are normally distributed with mean 187 mm and standard deviation is 7.1 mm.
This means that [tex]\mu = 187, \sigma = 7.1[/tex]
Suppose that 12 individuals are randomly chosen.
This means that [tex]n = 12, s = \frac{7.1}{\sqrt{12}} = 2.05[/tex]
What is the distribution of ¯ x?
By the Central Limit Theorem, the distribution of ¯ x is approximately normal with mean 187 and standard deviation 2.05.
Robin has a rectangular picture frame that is 8 1/2 by 11 inches. What is the
approximate perimeter of the picture frame in centimeters?
Answer: 99.06cm
Step-by-step explanation:
Note that 1 inch = 2.54cm
Therefore, we'll convert the sides of the frame in inches to cm. This will be:
8 1/2 inch = 8.5 × 2.54cm = 21.59cm
11inches = 11 × 2.54cm = 27.94cm
Therefore, the perimeter of a rectangle will be:
= 2(length + width)
= 2(27.94 + 21.59)
= 2(49.53)
= 99.06cm
Please help me. Photo provided
Help me I’ll make you expert !
35 points
(algebra one)
describe and correct the error in comparing the graphs
question in the image
How many students scored below 80?
11
19
cannot be determined from the histogram
9
Answer:
11
Step-by-step explanation:
I need this please help me
Answer:
C. Reflection over x- axis, down 6 right 3
Step-by-step explanation:
Which phrase best describes the figure below?
Answer:
B.
Step-by-step explanation:
It only has one base and it's a pentagon. Therefore, it's a pentagonal pyramid.
Question 2 Solve the problem below using a graphing calculator. Estimate o points
your answer to four decimal places
X^2= 4/x + ln(x)
A 1.5874
B 1.4596
C. 1.7241
D. 1.6985
A countries population in 1993 was 253 million. In 1999 it was 237 million. Estimate the population in 2007 using the exponential growth formula. round your answer to the nearest million.
Note: When solving for k, round to four decimal places.
Answer:
240 million
Step-by-step explanation:
I took the application
In ΔQRS, q = 890 cm, s = 810 cm and ∠S=120°. Find all possible values of ∠Q, to the nearest degree.
Answer: no possible triangles
Step-by-step explanation:
PLS ANSWER RN
Pierre is making a mural. He wants to cut a piece of tile to fit in between two others. He knows that one angle has to be 46°. What must m
A. 23
B. 24
C. 67
D. 134
Carol is making a pattern with toothpicks. The first five terms of Carol's pattern are shown.
Which expression can be used to find the number of toothpicks in Term n?
A. n +1
B. n +2
C. nt3
Ο Ο
D. 3n
E. 3n + 1
Answer:
B
Step-by-step explanation:
Let's make a table:
Term 1: 3 toothpicks
Term 2: 4 toothpicks
Term 3: 5 toothpicks
Term 4: 6 toothpicks
Term 5: 7 toothpicks
Term N = N + 2 toothpicks