Answer:
b
Step-by-step explanation:
30/3x=10
Marking Brainliest! 3(x-100)=?
Answer:
3x - 300
Step-by-step explanation:
Expand the brackets or use distribute law.
Answer:
[tex]3x - 300[/tex]solution,
[tex]3(x - 100) \\ = 3 \times x - 3 \times 100 \\ = 3x - 300[/tex]
hope this helps..
BIG Corporation advertises that its light bulbs have a mean lifetime, μ, of 2800 hours. Suppose that we have reason to doubt this claim and decide to do a statistical test of the claim. We choose a random sample of light bulbs manufactured by BIG and find that the mean lifetime for this sample is 2620 hours and that the sample standard deviation of the lifetimes is 650 hours.
In the context of this test, what is a Type II error?
A type II error is (rejecting/failing to reject) the hypothesis that μ is (less than/less than or equal to/greater than/greater than or equal to/not equal to/equal to) ____ when in fact, μ is (less than/less than or equal to/greater than/greater than or equal to/not equal to/equal to) ______.
Answer:
A type II error is failing to reject the hypothesis that μ is equal to 2800 when in fact, μ is less than 2800.
Step-by-step explanation:
A Type II error happens when a false null hypothesis is failed to be rejected.
The outcome (the sample) probability is still above the level of significance, so it is consider that the result can be due to chance (given that the null hypothesis is true) and there is no enough evidence to claim that the null hypothesis is false.
In this contest, a Type II error would be not rejecting the hypothesis that the mean lifetime of the light bulbs is 2800 hours, when in fact this is false: the mean lifetime is significantly lower than 2800 hours.
The time it takes me to wash the dishes is uniformly distributed between 10 minutes and 15 minutes. What is the probability that washing dishes tonight will take me between 12 and 14 minutes
Answer:
The probability that washing dishes tonight will take me between 12 and 14 minutes is 0.1333.
Step-by-step explanation:
Let the random variable X represent the time it takes to wash the dishes.
The random variable X is uniformly distributed with parameters a = 10 minutes and b = 15 minutes.
The probability density function of X is as follows:
[tex]f_{X}(x)=\frac{1}{b-a};\ a<X<b,\ a<b[/tex]
Compute the probability that washing dishes will take between 12 and 14 minutes as follows:
[tex]P(12\leq X\leq 14)=\int\limits^{12}_{14} {\frac{1}{15-10} \, dx[/tex]
[tex]=\frac{1}{5}\int\limits^{12}_{14} {1} \, dx \\\\=\frac{1}{5}\times [x]^{14}_{12}\\\\=\frac{1}{15}\times [14-12]\\\\=\frac{2}{15}\\\\=0.1333[/tex]
Thus, the probability that washing dishes tonight will take me between 12 and 14 minutes is 0.1333.
Which of the following represents the set of possible rational roots for the
polynomial shown below?
2^2+ 5^2 – 8x– 10 = 0
6.1.3
What requirements are necessary for a normal probability distribution to be a standard normal probability distribution?
Answer:
μ = 0σ = 1Step-by-step explanation:
A standard normal probability distribution is a normal distribution that has a mean of zero and a standard deviation of 1.
Which equation represents a line that passes through (2,-2) and has a slope of 3?
y-2 = 3(x +
y – 3 = 2(x + ?)
y +
= 3(x - 2)
y +
= 2(x - 3)
Make a matrix A whose action is described as follows: The hit by A rotates everything Pi/4 counterclockwise radians, then stretches by a factor of 1.8 along the x-axis and a factor of 0.7 along the y-axis and then rotates the result by Pi/3 clockwise radians.
Answer:
The required matrix is[tex]A = \left[\begin{array}{ccc}1.07&-0.21\\-0.86&1.35\end{array}\right][/tex]
Step-by-step explanation:
Matrix of rotation:
[tex]P = \left[\begin{array}{ccc}cos\pi/4&-sin\pi/4\\sin\pi/4&cos\pi/4\end{array}\right][/tex]
[tex]P = \left[\begin{array}{ccc}1/\sqrt{2} &-1/\sqrt{2} \\1/\sqrt{2} &1/\sqrt{2}\end{array}\right][/tex]
x' + iy' = (x + iy)(cosθ + isinθ)
x' = x cosθ - ysinθ
y' = x sinθ + ycosθ
In matrix form:
[tex]\left[\begin{array}{ccc}x'\\y'\end{array}\right] = \left[\begin{array}{ccc}cos\theta&-sin\theta\\sin \theta&cos\theta\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right][/tex]
The matrix stretches by 1.8 on the x axis and 0.7 on the y axis
i.e. x' = 1.8x
y' = 0.7y
[tex]\left[\begin{array}{ccc}x'\\y'\end{array}\right] = \left[\begin{array}{ccc}1.8&0\\0&0.7\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right][/tex]
[tex]Q = \left[\begin{array}{ccc}1.8&0\\0&0.7\end{array}\right][/tex]
According to the question, the result is rotated by pi/3 clockwise radians
[tex]R = \left[\begin{array}{ccc}cos(-\pi/3)& -sin(-\pi/3)\\-sin(\pi/3)&cos(\pi/3)\end{array}\right][/tex]
[tex]R = \left[\begin{array}{ccc}1/2&\sqrt{3}/2 \\-\sqrt{3}/2 &1/2\end{array}\right][/tex]
To get the matrix A, we would multiply matrices R, Q and P together.
[tex]A = RQP = \left[\begin{array}{ccc}1/2&\sqrt{3}/2 \\-\sqrt{3}/2 &1/2\end{array}\right] \left[\begin{array}{ccc}1.8&0\\0&0.7\end{array}\right] \left[\begin{array}{ccc}1/\sqrt{2} &-1/\sqrt{2} \\1/\sqrt{2} &1/\sqrt{2}\end{array}\right][/tex]
[tex]A = \left[\begin{array}{ccc}1.07&-0.21\\-0.86&1.35\end{array}\right][/tex]
Jennifer has carpet in her square bedroom. She decides to also purchase carpet for her living room which is rectangular in shape and 9 feet longer than her bedroom.
The area of the carpet required in the living room is given by the quadratic expression below, where x represents the side length, in feet, of the carpet in the bedroom.
X^2 + 9X
Match each part of the expression with what is represents.
Answer/Step-by-step explanation:
Let's highlight the dimensions of the bedroom and living room using the information given in the question:
==>Squared Bedroom dimensions:
Side length = w = x ft
Area = x*x = x²
==>Rectangular living room dimensions:
width = side length of the squared bedroom = x
length = (x + 9) ft
Area = L*W = x*(x+9) = x² + 9x
Now let's match each given expression with what they represent:
==>"the monomial, x, a factor of the expression x² + 9x" represents "the width of the carpet in the living room"
As we have shown in the dimensions of the squared bedroom above.
==>"the binomial, (x + 9), a factor of the expression x² + 9x" represents "the length of the carpet in the living room" as shown above in the dimensions for living room
==>"the second-degree term of the expression x² + 9x" represents "the area of the carpet in the bedroom"
i.e. the 2nd-degree term in the expression is x², which represents the area of the carpet of the given bedroom.
==>"the first-degree term of the expression x2 + 9x" represents "the increase in the area of carpet needed for the living room".
i.e. 1st-degree term in the expression is 9x. And it represents the increase in the area of the carpet for the living room. Area of bedroom is x². Area of carpet needed for living room increased by 9x. Thus, area of carpet needed for living room = x² + 9x
In a random sample 765 adults in the United States, 322 say they could not cover a $400 unexpected expense without borrowing money or going into debt. (a) What population is under consideration in the data set
Answer:
The population under consideration in the data set are all the adults in the United States.
Step-by-step explanation:
Sampling
This is a common statistics practice, when we want to study something from a population, we find a sample of this population.
For example:
I want to estimate the proportion of New York state residents who are Buffalo Bills fans. So i ask, lets say, 1000 randomly selected New York state residents wheter they are Buffalo Bills fans, and expand this to the entire population of New York State residents.
The population of interest are all the residents of New York State.
In this question:
Sample of 765 adults in the United states.
So the population under consideration in the data set are all the adults in the United States.
An expression is shown below: 3pf^2 − 21p^2f + 6pf − 42p^2 Part A: Rewrite the expression by factoring out the greatest common factor. (4 points) Part B: Factor the entire expression completely. Show the steps of your work. (6 points)
Hey there! I'm happy to help!
PART A
Let's break down each terms in the expression to find the factors that make it up and see the greatest thing they all have in common
To break up the numbers, we keep on dividing it until there are only prime numbers left.
TERM #1
Three is a prime number, so there is no need to split it up.
3pf²= 3·p·f·f
TERM #2
We have a negative coefficient here. First, let's ignore the negative sign and find all of the factors, which are just 7 and 3. One of them has to be negative and one has to be positive for it to be negative. It could be either way, and when comparing to other, we might want one to be negative or positive to match another part of the expression to find the greatest common factor. So, we will use the plus or minus sign ±, knowing that one must be positive and one must be negative.
-21p²2f= ±7·±3 (must be opposite operations) ·p·p·f
TERM #3
6pf= 2·3·p·f
TERM #4
Since 42 is made up of 3 prime factors (2,3,7), one of them or all three must be negative, because two negatives would make it positive. We will use the plus-minus sign again on all three because it could be just one is negative or all three are, but we don't know. We can use these later to find the greatest common factor when matching.
-42p²= ±2·±3·±7·p·p
Now, let's pull out all of our factors and see the greatest thing all four terms have in common
TERM 1: 3·p·f·f
TERM 2: ±7·±3·p·p·f (7 and 3 must end up opposite signs)
TERM 3: 2·3·p·f
TERM 4: ±2·±3·±7·p·p (one or three of the coefficients will be negative)
Let's first look at the numbers they share. All of them have a three. We will rewrite Term 2 as -7·3·p·p·f afterwards because 3 must be positive to match. With term four, the 3 has to positive so not all three can be negative, so that means that either the 2 or 7 has to be negative, but in the end we they will make a -14 so it does not matter which one because.
Now, with variables. All of them have one p, so we will keep this.
Almost all had an f except the fourth, so this cannot be part of the GCF.
So, all the terms have 3p in common. Let's take the 3p out of each term and see what we have left. In term 4 we will combine our ±7 and ±2 to be -14 because one has to be negative.
TERM 1: f·f
TERM 2: -7·p·f
TERM 3: 2·f
TERM 4: -14·p
The way we will write this is we will put 3p outside parentheses and put what is left of all of our terms on the inside of the parentheses.
3p(f·f+-7·p·f+2·f-14·p)
We simplify these new terms.
3p(f²-7pf+2f-14p)
Now we combine like terms.
3p(f²-7pf-14p)
If you used the distributive property to undo the parentheses you could end up with our original expression.
PART B
Completely factoring means the equation is factored enough that you cannot factor anymore. The only things we have left to factor more are the terms inside the parentheses. Although there won't be something common between all of them, one might have pairs with one and not another, and this can still be factored out, and this can be put into (a+b)(a+c). Let's find what we have in common with the three terms in the parentheses.
TERM 1: f·f
TERM 2: -7·p·f
TERM 3: 2· -7·p (I just put 7 as negative and 2 as positive already for matching)
Term 1 and 2 have an f in common.
Terms 2 and 3 have a -7p in common.
So, we see that the f and the -7p are what can be factored out among all of the terms, so let's take it out of all of them and see what is left.
Term 1: f
Term 2: nothing left here
Term 3: 2
So, this means that all we have left is f+2. If we multiply that by f-7p we will have what was in the parentheses in our answer from Part A, and we cannot simplify this any further. This means that our parentheses from Part A= (f-7p)(f+2). This shows that (f-7p) is multiplied by (f+2)
Don't forget the GCF 3p; that's still outside the parentheses!
Therefore, the answer here is 3p(f-7p)(f+2).
Have a wonderful day! :D
Find the volume & surface area of a cylinder with radius 4 cm and height 9 cm
Answer:
V= 452.39cm³ (to 2 d.p. )
S.A. = 326.73cm² (to 2 d.p. )
Step-by-step explanation:
Vcylinder = π r² h = π (4)² (9) = 144 π = 452.3893421cm³ = 452.39cm³ (to 2 d.p. )
S.A. cylinder = 2π r h + 2π r² = 2π (4)(9) + 2π (4)² = 104π = 326.725636cm² = 326.73cm² (to 2 d.p. )
Someone help me please
The Mathalot Company makes and sells textbooks. They have one linear function that represents the cost of producing textbooks and another linear function that models how much income they get from those textbooks. Describe the key features that would determine if these linear functions ever intercepted. (10 points)
The polynomial-7.5x^2 + 103 + 2142 models the yearly number of visitors (in thousands) x years after 2007 to a park. Use this polynomial to estimate the number of visitors to the park in 2021.
Answer:
In that year approximately 2114 thousand people visited the park.
Step-by-step explanation:
Since the expression [tex]y(x) = -7.5*x^2 + 103*x + 2142[/tex] models the number of visitors in the park, where x represents the number of years after 2007 and 2021 is 14 years after that, then we need to find "y" for that as shown below.
[tex]y(14) = -7.5*(14)^2 + 103*14 + 2142\\y(14) = -7.5*196 + 1442 + 2142\\y(14) = -1470 + 3584\\y(14) = 2114[/tex]
In that year approximately 2114 thousand people visited the park.
if a to the power x by y is equal to 1 then the value of x is
Answer:
a^x/y=1 x: 0
Step-by-step explanation: w.k.t, a^0=1( any variable raised to 0 is 1)
so, here the exponent is x/y which should have been 0 so that answer was 1.
When Vlad moved to his new home a few years ago, there was a young oak tree in his backyard. He measured it once a year and found that it grew by 26 centimeters each year. 4.5 years after he moved into the house, the tree was 292 centimeters tall. How tall was the tree when Vlad moved into the house? centimeters How many years passed from the time Vlad moved in until the tree was 357 centimeters tall? years
Answer:
The tree was 175 centimeters tall when Vlad moved into the house.
7 years passed from the time Vlad moved in until the tree was 357 centimeters tall.
Step-by-step explanation:
The height of the tree, in centimeters, in t years after Vlad moved into the house is given by an equation in the following format:
[tex]H(t) = H(0) + at[/tex]
In which H(0) is the height of the tree when Vlad moved into the house and a is the yearly increase.
He measured it once a year and found that it grew by 26 centimeters each year.
This means that [tex]a = 26[/tex]
So
[tex]H(t) = H(0) + 26t[/tex]
4.5 years after he moved into the house, the tree was 292 centimeters tall. How tall was the tree when Vlad moved into the house?
This means that when t = 4.5, H(t) = 292. We use this to find H(0).
[tex]H(t) = H(0) + 26t[/tex]
[tex]292 = H(0) + 26*4.5[/tex]
[tex]H(0) = 292 - 26*4.5[/tex]
[tex]H(0) = 175[/tex]
The tree was 175 centimeters tall when Vlad moved into the house.
How many years passed from the time Vlad moved in until the tree was 357 centimeters tall?
This is t for which H(t) = 357. So
[tex]H(t) = H(0) + 26t[/tex]
[tex]H(t) = 175 + 26t[/tex]
[tex]357 = 175 + 26t[/tex]
[tex]26t = 182[/tex]
[tex]t = \frac{182}{26}[/tex]
[tex]t = 7[/tex]
7 years passed from the time Vlad moved in until the tree was 357 centimeters tall.
Help! Just a little more
Answer:
x = 7
y = 8
Step-by-step explanation:
4y-4 = 28
4y = 32
y = 8
10x+65 = 135
10x = 70
x = 7
Answer:
Step-by-step explanation:
(4y-4)=28
4y=32
y=8
(10x+65)=135
10x=70
x=7
is a parallelogram sometimes always or never a trapezoid
yes
Step-by-step explanation:
parallelogram are quadrilaterals with two sets of parallel sides. since square must be quadrilaterals with two sets of parallel sides ,then all squares are parallelogram ,a trapezoid is quadrilateral.
The scientist performs additional analyses and observes that the number of major earthquakes does appear to be decreasing but wonders whether the relationship is statistically significant. Based on the partial regression output below and a 5% significance level, is the year statistically significant in determining the number of earthquakes above magnitude 7.0?Dependent Variable: Earthquakes above Magnitude 7.0 Coefficients Standard t Stat P-value Lower 95% Upper 95% ErrorIntercept 64.67 38.08 4.32 89.22 240.12Year -0.07 0.02 -3.82 -0.11 -0.04
Answer:
Step-by-step explanation:
Hello!
A regression model was determined in order to predict the number of earthquakes above magnitude 7.0 regarding the year.
^Y= 164.67 - 0.07Xi
Y: earthquake above magnitude 7.0
X: year
The researcher wants to test the claim that the regression is statistically significant, i.e. if the year is a good predictor of the number of earthquakes with magnitude above 7.0 If he is correct, you'd expect the slope to be different from zero: β ≠ 0, if the claim is not correct, then the slope will be equal to zero: β = 0
The hypotheses are:
H₀: β = 0
H₁: β ≠ 0
α: 0.05
The statistic for this test is a student's t: [tex]t= \frac{b - \beta }{Sb} ~~t_{n-2}[/tex]
The calculated value is in the regression output [tex]t_{H_0}= -3.82[/tex]
This test is two-tailed, meaning that the rejection region is divided in two and you'll reject the null hypothesis to small values of t or to high values of t, the p-value for this test will also be divided in two.
The p-value is the probability of obtaining a value as extreme as the one calculated under the null hypothesis:
p-value: [tex]P(t_{n-2}\leq -3.82) + P(t_{n-2}\geq 3.82)[/tex]
As you can see to calculate it you need the information of the sample size to determine the degrees of freedom of the distribution.
If you want to use the rejection region approach, the sample size is also needed to determine the critical values.
But since this test is two tailed at α: 0.05 and there was a confidence interval with confidence level 0.95 (which is complementary to the level of significance) you can use it to decide whether to reject the null hypothesis.
Using the CI, the decision rule is as follows:
If the CI includes the "zero", do not reject the null hypothesis.
If the CI doesn't include the "zero", reject the null hypothesis.
The calculated interval for the slope is: [-0.11; -0.04]
As you can see, both limits of the interval are negative and do not include the zero, so the decision is to reject the null hypothesis.
At a 5% significance level, you can conclude that the relationship between the year and the number of earthquakes above magnitude 7.0 is statistically significant.
I hope this helps!
(full output in attachment)
Pls help me find the volume of this solid
Answer:
240cm³
Step-by-step explanation:
First, let's assume the entire shape is full rectangular prism without that has the middle being cut out.
What this means is that, to get the volume of the solid made out of clay, we would calculate the solid as a full rectangular prism, then find the volume of the assumed middle cut-out portion. Then find the difference between both.
Let's solve:
Find the volume of the rectangular prism assuming the solid is full:
Volume of prism = width (w) × height (h) × length (l)
w = 4cm
h = 7cm
l = 3+6+3 = 12cm
Volume of full solid = 4*7*12 = 336cm³
Next, find the volume of the assumed cut-out portion using same formula for volume of rectangular prism:
w = 4cm
h = 7-3 = 4cm
l = 6cm
Volume of assumed cut-out portion = 4*4*6 = 96cm³
Volume of solid made from clay = 336cm³ - 96cm³ = 240cm³
Will mark as brainliess and thanks for awnsering this simple question
Answer:
x=-2
Step-by-step explanation:
2 times -2=-4+3=-1
At a high school, 9th and 10th graders were asked whether they would prefer
robotics or art as an elective. The results are shown in the relative frequency
table.
To the nearest percent, what percentage of 10th graders surveyed preferred robotics?
Using the percentage concept, it is found that 51% of 10th graders surveyed preferred robotics, hence option B is correct.
What is a percentage?The percentage of an amount a over a total amount b is given by a multiplied by 100% and divided by b, that is:
[tex]P = \frac{a}{b} \times 100\%[/tex]
In this problem, we have that 33% out of 65% of the students are 7th graders who preferred robotics, hence the percentage is given by:
[tex]P = \frac{33}{65} \times 100\% = 51%[/tex]
Which means that option B is correct.
More can be learned about percentages at https://brainly.com/question/14398287
#SPJ1
Answer:
It's A. 61% The dude above me is wrong.
Step-by-step explanation:
I just took the test
In how many ways can you put seven marbles in different colors into two jars? Note that the jars may be empty.
ith 0 identical marbles permitted to be included in any of the jars, An expression can be developed to determine the total of marbles in jar arrangements, which is:
E = [(n+j -1)!]*{1/[(j-1)!]*[(n)!]}, where n = number of identical balls and j =number of distinct jars, the contents of all of which must sum to n for each marbles in j jars arrangement. With n = 7 and j = 4. E = 10!/(3!)(7!) = 120= number of ways 7 identical marbles can be distributed to 4 distinct jars such that up to 3 boxes may be empty and the maximum to any box is 7 balls.i think is the answer
If TU = 6 units, what must be true? SU + UT = RT RT + TU = RS RS + SU = RU TU + US = RS
Answer:
Since RT = 12, TU = 6 and RS = 24, T and U are the midpoints of RS and TS respectively. This means that SU + UT = RT.
Answer:
su+ut=rt
Step-by-step explanation:
An experiment consists of dealing 7 cards from a standard deck of 52 playing cards. What is the probability of being dealt exactly 4 clubs and 3 spades?
Answer: 0.00153
Step-by-step explanation:
Given: An experiment consists of dealing 7 cards from a standard deck of 52 playing cards.
Number of ways of dealing 7 cards from 52 cards = [tex]^{52}C_7[/tex]
Since there are 13 clubs and 13 spades.
Number of ways of getting exactly 4 clubs and 3 spades=[tex]^{13}C_4\times\ ^{13}C_3[/tex]
Now, the probability of being dealt exactly 4 clubs and 3 spades
[tex]=\dfrac{^{13}C_4\times\ ^{13}C_3}{^{52}C_7}\\\\\\=\dfrac{{\dfrac{13!}{4!(9!)}\times\dfrac{13!}{3!10!}}}{\dfrac{52!}{7!45!}}\\\\=\dfrac{715\times286}{133784560}\\\\=0.00152850224271\approx0.00153[/tex]
Hence, the probability of being dealt exactly 4 clubs and 3 spades = 0.00153
The nth term of a geometric sequence is given by an = 27(0.1)n - 1. Write the first five terms of this sequence.
Answer:
The first first five terms of this sequence are
27 ,2.7 ,0.27 ,0.027 , 0.0027Step-by-step explanation:
[tex]a(n) = 27(0.1)^{n - 1} [/tex]
where n is the number of term
For the first term
n = 1
[tex]a(1) = 27(0.1)^{1 - 1} = 27(0.1) ^{0} [/tex]
= 27(1)
= 27Second term
n = 2
[tex]a(2) = 27(0.1)^{2 - 1} = 27(0.1)^{1} [/tex]
= 27(0.1)
= 2.7Third term
n = 3
[tex]a(3) = 27(0.1)^{3 - 1} = 27(0.1)^{2} [/tex]
= 0.27Fourth term
n = 4
[tex]a(4) = 27(0.1)^{4 - 1} = 27(0.1)^{3} [/tex]
= 0.027Fifth term
n = 5
[tex]a(5) = 27(0.1)^{5 - 1} = 27(0.1)^{4} [/tex]
= 0.0027Hope this helps you
Use the graph to find estimates of the solutions to the equation x2 + x-6=-2
Answer:
The solutions are the roots of the quadratic. They are found where the graph crosses the x-axis.
Step-by-step explanation:
Simplify -4 • -4 • -4
Answer: -64
Step-by-step explanation: Since we know that -4 x -4 is a positive, it equals 16, then a positive plus a negative equals a negative, so 16 x -4 equals -64
Answer:
-64
Step-by-step explanation:
-4 • -4 • -4
-4*-4 = 16
16*-4
-64
What’s the probability of getting each card out of a deck?
Determine the probability of drawing the card(s) at random from a well-shuffled regular deck of 52 playing cards.
a. a seven __________
b. a six of clubs. ___________
c. a five or a queen ___________
d. a black card. ___________
e. a red card or a jack. ___________
f. a club or an ace. ___________
g. a diamond or a spade. ___________
Answer:
a. 1/13
b. 1/52
c. 2/13
d. 1/2
e. 15/26
f. 17/52
g. 1/2
Step-by-step explanation:
a. In a deck of cards, there are 4 suits and each of them has a 7. Therefore, the probability of drawing a 7 is:
P(7) = 4/52 = 1/13
b. There is only one 6 of clubs, therefore, the probability of drawing a 6 of clubs is:
P(6 of clubs) = 1/52
c. There 4 fives (one for each suit) and 4 queens in a deck of cards. Therefore, the probability of drawing a five or a queen is:
P(5 or Q) = P(5) + P(Q)
= 4/52 + 4/52
= 1/13 + 1/13
P(5 or Q) = 2/13
d. There are 2 suits that are black. Each suit has 13 cards. Therefore, there are 26 black cards. The probability of drawing a black card is:
P(B) = 26/52 = 1/2
e. There are 2 suits that are red. Each suit has 13 cards. Therefore, there are 26 red cards. There are 4 jacks. Therefore:
P(R or J) = P(R) + P(J)
= 26/52 + 4/52
= 30/52
P(R or J) = 15/26
f. There are 13 cards in clubs suit and there are 4 aces, therefore:
P(C or A) = P(C) + P(A)
= 13/52 + 4/52
P(C or A) = 17/52
g. There are 13 cards in the diamonds suit and there are 13 in the spades suit, therefore:
P(D or S) = P(D) + P(S)
= 13/52 + 13/52
= 26/52
P(D or S) = 1/2
Suppose a polling agency reported that 44.4% of registered voters were in favor of raising income taxes to pay down the national debt. The agency states that results are based on telephone interviews with a random sample of 1049 registered voters. Suppose the agency states the margin of error for 95% confidence is 3.0%. Determine and interpret the confidence interval for the proportion of registered voters who are in favor of raising income taxes to pay down the national debt.
Answer:
95% of confidence interval for the proportion of registered voters who are in favor of raising income taxes to pay down the national debt.
(0.414 ,0.474)
Step-by-step explanation:
Step(i):-
Given sample proportion
p⁻ = 44.4 % = 0.444
Random sample size 'n' = 1049
Given margin of error for 95% confidence level = 3 % = 0.03
Step(ii):-
95% of confidence interval for the proportion is determined by
[tex](p^{-} - Z_{\alpha }\sqrt{\frac{p^{-} (1-p^{-} }{n} } , p^{-} + Z_{\alpha }\sqrt{\frac{p^{-} (1-p^{-} }{n} })[/tex]
we know that
Margin of error for 95% confidence level is determined by
[tex]M.E = Z_{\alpha }\sqrt{\frac{p^{-} (1-p^{-}) }{n} }[/tex]
Step(iii):-
Now
95% of confidence interval for the proportion is determined by
[tex](p^{-} - M.E, p^{-} + M.E)[/tex]
Given Margin of error
M.E = 0.03
Now 95% of confidence interval for the proportion
[tex](0.444 - 0.03, 0.444+ 0.03)[/tex]
(0.414 ,0.474)
Conclusion:-
95% of confidence interval for the proportion of registered voters who are in favor of raising income taxes to pay down the national debt.
(0.414 ,0.474)