Answer:
[tex]\int (x+ 1) \sqrt{2x-1} dx = \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{15}(2x-1)^{\frac{5}{2}} + C[/tex]
Step-by-step explanation:
[tex]\int (x+1)\sqrt {(2x-1)} dx\\Integrate \ using \ integration \ by\ parts \\\\u = x + 1, v'= \sqrt{2x - 1}\\\\v'= \sqrt{2x - 1}\\\\integrate \ both \ sides \\\\\int v'= \int \sqrt{2x- 1}dx\\\\v = \int ( 2x - 1)^{\frac{1}{2} } \ dx\\\\v = \frac{(2x - 1)^{\frac{1}{2} + 1}}{\frac{1}{2} + 1}} \times \frac{1}{2}\\\\v= \frac{(2x - 1)^{\frac{3}{2}}}{\frac{3}{2}} \times \frac{1}{2}\\\\v = \frac{2 \times (2x - 1)^{\frac{3}{2}}}{3} \times \frac{1}{2}\\\\v = \frac{(2x - 1)^{\frac{3}{2}}}{3}[/tex]
[tex]\int (x+1)\sqrt(2x-1)dx\\\\ = uv - \int v du[/tex]
[tex]= (x +1 ) \cdot \frac{(2x - 1)^{\frac{3}{2}}}{3} - \int \frac{(2x - 1)^{\frac{3}{2}}}{3} dx \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [ \ u = x + 1 => du = dx \ ][/tex]
[tex]= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \int (2x - 1)^{\frac{3}{2}}} dx\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \times ( \frac{(2x-1)^{\frac{3}{2} + 1}}{\frac{3}{2} + 1}) \times \frac{1}{2}\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \times ( \frac{(2x-1)^{\frac{5}{2}}}{\frac{5}{2} }) \times \frac{1}{2}\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{15} \times (2x-1)^{\frac{5}{2}} + C\\\\[/tex]
A rectangular garden is 5 ft longer than it is wide. Its area is 1800ft^2. What are its dimensions?
Answer:
The dimensions are 45 feet by 40 feet.
Step-by-step explanation:
Recall that the area of a rectangle is given by:
[tex]\displaystyle A=w\ell[/tex]
Where w is the width and l is the length.
The length is five feet longer than the width. Thus, we can write that:
[tex]\ell = w+5[/tex]
The total area is 1800 square feet. Substitute:
[tex]1800=w(w+5)[/tex]
Solve for w. Distribute:
[tex]w^2+5w=1800[/tex]
Subtract 1800 from both sides:
[tex]w^2+5w-1800=0[/tex]
Factor. We can use 45 and -40. Hence:
[tex]\displaystyle (w+45)(w-40)=0[/tex]
Zero Product Property:
[tex]w+45=0\text{ or } w-40=0[/tex]
Solve for each case:
[tex]\displaystyle w=-45\text{ or } w=40[/tex]
Since the width cannot be negative, we can ignore the first solution.
So, the width is 40 feet. Since the length is five feet longer, the length is 45 feet.
The dimensions are 45 feet by 40 feet.
Answer pls:) I would really appreciate it
Answer:
1. C
2. B
3 A
4. A
Step-by-step explanation:
#1
Brady starts off with 12 coins
And buys 6 more coins every year
So add 6 to find number of coins he will have the next year until we've done it five times ( because we want to find how many he will have after 5 years )
12 ( 1st year )
Add 6
12 + 6 = 18 ( 2nd year )
Add 6
18 + 6 = 24 ( 3rd year )
Add 6
24 + 6 = 30 ( 4th year )
Add 6
30 + 6 = 36 ( 5th year )
By the fifth year he will have 36 coins and the sequence would be
12, 18, 24, 30, 36
Which corresponds with answer choice C
2
15, 19, 23, 27, ?
We want to find the next term
To do so we must find the common difference
We can do this by subtracting the last given term by the term before it
27 - 23 = 4
Just to clarify we can do the terms before those
19 - 15 = 4
So the common difference is 4
Now to find the next term we simply add 4 to the last given term
27 + 4 = 31
The next term would be 31
3. Cumulative property of addition states that you can add any 3 numbers in a different order and they will be the same
a + b + 2 = 2 + a + b
Same variables and numbers just different order
Therefore this is an example of cumulative property of addition
4. The GCF ( greatest common factor ) is the greatest number that the two numbers can be divided by
18a and 24ab
Factors of 18
2 , 9 , 6, 3 , 1 and 18
Factors of 24
24, 1, 2, 12, 6, 4, 3 and 8
The greatest factor that both 18 and 24 have is 6
The GCF would be 6a ( not 6 ) because both numbers share a common variable (a) ( 18a , 24ab )
3x=4(c-d)/d make d the subject
Answer:
[tex]d = \frac{4c}{3x + 4} [/tex]
Step-by-step explanation:
[tex]3x = \frac{4(c - d)}{d} [/tex]
Multiply both sides by d:
[tex]3xd = 4(c - d)[/tex]
Expand:
[tex]3xd = 4c \: - 4d[/tex]
+4d on both sides:
[tex]3xd + 4d = 4c[/tex]
Factorise d out of the left-hand side:
[tex]d(3x + 4) = 4c[/tex]
Divide both sides by (3x +4):
[tex]d = \frac{4c}{3x + 4} [/tex]
find the Maclaurin series for f(x) using the definition of a Maclaurin series. [Assume that f has a power series expansion. Do not show that Rn(x) → 0.] Find the associated radius of convergence R. f(x) = 6(1 − x)−2 Step 1 The Maclaurin series formula is f(0) + f '(0)x + f ''(0) 2! x2 + f '''(0) 3! x3 + f (4)(0) 4! x4 + .
Answer:
= ∑ 6*n*x^n-1
Radius of convergence = 1
Step-by-step explanation:
f(x) = 6(1-x)^-2
Maclaurin series can be expressed using the formula
f(x) = f(0) + f '(0)x + f ''(0)/ 2! (x)^2 + f '''(0)/3! (x)^3 + f (4)(0) 4! x4 + .
attached below is the detailed solution
Radius of convergence = 1
The Maclaurin series for f(x) = 6 / (1 - x )^2 = ∑ 6*n*x^n-1 ( boundary ; ∞ and n = 1 )
A manufacturer of nails claims that only 4% of its nails are defective. A random sample of 20 nails is selected, and it is found that two of them, 10%, are defective. Is it fair to reject the manufacturer's claim based on this observation?
Answer:
The p-value of the test is 0.0853 > 0.05, which means that there is not enough evidence to reject the manufacturer's claim based on this observation.
Step-by-step explanation:
A manufacturer of nails claims that only 4% of its nails are defective.
At the null hypothesis, we test if the proportion is of 4%, that is:
[tex]H_0: p = 0.04[/tex]
At the alternative hypothesis, we test if the proportion is more than 4%, that is:
[tex]H_a: p > 0.04[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
4% is tested at the null hypothesis
This means that [tex]\mu = 0.04, \sigma = \sqrt{0.04*0.96}[/tex]
A random sample of 20 nails is selected, and it is found that two of them, 10%, are defective.
This means that [tex]n = 20, X = 0.1[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{0.1 - 0.04}{\frac{\sqrt{0.04*0.96}}{\sqrt{20}}}[/tex]
[tex]z = 1.37[/tex]
P-value of the test and decision:
Considering an standard significance level of 0.05.
The p-value of the test is the probability of finding a sample proportion above 0.1, which is 1 subtracted by the p-value of z = 1.37.
Looking at the z-table, z = 1.37 has a p-value of 0.9147
1 - 0.9147 = 0.0853
The p-value of the test is 0.0853 > 0.05, which means that there is not enough evidence to reject the manufacturer's claim based on this observation.
Answer:
Considering an standard significance level of 0.05.
The p-value of the test is the probability of finding a sample proportion above 0.1, which is 1 subtracted by the p-value of z = 1.37.
Looking at the z-table, z = 1.37 has a p-value of 0.9147
1 - 0.9147 = 0.0853
The p-value of the test is 0.0853 > 0.05, which means that there is not enough evidence to reject the manufacturer's claim based on this observation.
Step-by-step explanation:
the least value of x²-3x+5 is..
11/4
Step-by-step explanation:
to find the minimum value we require to find the vertex and determine if max/min
for a quadratic in standard form ; ax² + bx + c
the coordinate of the vertex is..
xvertex = -b/2a
x² - 3x + 5 is in standard form with a = 1,b = - 3 and c = 5
xvertex = - , -3/2 = 3/2
substitute this value into the equation for y-coordinate
yvertex = ( 3/2 ) ² -3 (3/2) + 5 = 11/4
vertex = ( 3/2, 11/4 )
to determine whether max/min
• if a > 0 then minimum u
• ifa < 0 then maximum n
here a = 1 > 0 hence minimum
minimum value of x² - 3x + 5 is 11/4
hope you understand this :)
Floataway Tours has $420,000 that can be use to purchase new rental boats for hire during the summer. The boats can be purchased from two different manufacturers. Floataway Tours would like to purchase at least 50 boats and would like to purchase the same number from Sleekboat as from Racer to maintain goodwill. At the same time,Floataway Tours wishes to have a total seating capacity of at least 200.
Required:
Formulate this problem as a linear program.
Answer and explanation:
A linear problem is an equation based on known and unknown variables that follow a linear path, usually without exponents and look like this:
y=mx+b. To formulate the linear constraints of the problem above, we look at the unknown variables and known variables and define and equation using this.
From the problem, assume x and y are the prices of the different boat brands:
50x+50y=420000
Assume a and b are number of x brand boats and y brand boats supplied thus:
a+b>=200
Evaluate the given expression for x=7.
8x +9
The answer is ---
Answer:
The answer is 65
Step-by-step explanation:
Evaluate:
8x + 9
When x = 7
Use PEMDAS order of operations:
8x + 9
= 8(7) + 9
= 56 + 9
= 65
Hope this helps
x - 3y +3=0
a) The length of the perpendicular drawn from the point (a, 3) on the line
3x + 4y + 5 = 0 is 4. Find the value of a.
Answer:
We know that for a line:
y = a*x + b
where a is the slope and b is the y-intercept.
Any line with a slope equal to -(1/a) will be perpendicular to the one above.
So here we start with the line:
3x + 4y + 5 = 0
let's rewrite this as:
4y = -3x - 5
y = -(3/4)*x - (5/4)
So a line perpendicular to this one, has a slope equal to:
- (-4/3) = (4/3)
So the perpendicular line will be something like:
y = (4/3)*x + c
We know that this line passes through the point (a, 3)
this means that, when x = a, y must be equal to 3.
Replacing these in the above line equation, we get:
3 = (4/3)*a + c
c = 3 - (4/3)*a
Then the equation for our line is:
y = (4/3)*x + 3 - (4/3)*a
We can rewrite this as:
y = (4/3)*(x -a) + 3
now we need to find the point where this line ( y = -(3/4)*x - (5/4)) and the original line intersect.
We can find this by solving:
(4/3)*(x -a) + 3 = y = -(3/4)*x - (5/4)
(4/3)*(x -a) + 3 = -(3/4)*x - (5/4)
(4/3)*x - (3/4)*x = -(4/3)*a - 3 - (5/4)
(16/12)*x - (9/12)*x = -(4/3)*a - 12/4 - 5/4
(7/12)*x = -(4/13)*a - 17/4
x = (-(4/13)*a - 17/4)*(12/7) = - (48/91)*a - 51/7
And the y-value is given by inputin this in any of the two lines, for example with the first one we get:
y = -(3/4)*(- (48/91)*a - 51/7) - (5/4)
= (36/91)*a + (153/28) - 5/4
Then the intersection point is:
( - (48/91)*a - 51/7, (36/91)*a + (153/28) - 5/4)
And we want that the distance between this point, and our original point (3, a) to be equal to 4.
Remember that the distance between two points (a, b) and (c, d) is:
distance = √( (a - c)^2 + (b - d)^2)
So here, the distance between (a, 3) and ( - (48/91)*a - 51/7, (36/91)*a + (153/28) - 5/4) is 4
4 = √( (a + (48/91)*a + 51/7)^2 + (3 - (36/91)*a + (153/28) - 5/4 )^2)
If we square both sides, we get:
4^2 = 16 = (a + (48/91)*a + 51/7)^2 + (3 - (36/91)*a - (153/28) + 5/4 )^2)
Now we need to solve this for a.
16 = (a*(1 + 48/91) + 51/7)^2 + ( -(36/91)*a + 3 - 5/4 + (153/28) )^2
16 = ( a*(139/91) + 51/7)^2 + ( -(36/91)*a - (43/28) )^2
16 = a^2*(139/91)^2 + 2*a*(139/91)*51/7 + (51/7)^2 + a^2*(36/91)^2 + 2*(36/91)*a*(43/28) + (43/28)^2
16 = a^2*( (139/91)^2 + (36/91)^2) + a*( 2*(139/91)*51/7 + 2*(36/91)*(43/28)) + (51/7)^2 + (43/28)^2
At this point we can see that this is really messy, so let's start solving these fractions.
16 = (2.49)*a^2 + a*(23.47) + 55.44
0 = (2.49)*a^2 + a*(23.47) + 55.44 - 16
0 = (2.49)*a^2 + a*(23.47) + 39.44
Now we can use the Bhaskara's formula for quadratic equations, the two solutions will be:
[tex]a = \frac{-23.47 \pm \sqrt{23.47^2 - 4*2.49*39.4} }{2*2.49} \\\\a = \frac{-23.47 \pm 12.57 }{4.98}[/tex]
Then the two possible values of a are:
a = (-23.47 + 12.57)/4.98 = -2.19
a = (-23.47 - 12.57)/4.98 = -7.23
what ordered pair makes both inequalities true
-3,5
-2,2
-1,-3
0,-1
Answer:
(-2, 2)
Step-by-step explanation:
(-2, 2) is the only ordered pair that makes both inequalities true.
Answer:
B
Step-by-step explanation:
got it right
WILL GIVE MOST BRAINIEST
Which of the following functions best describes this graph?
A. y (x + 4) (x + 5)
Answer:
D. y =
Step-by-step explanation:
The solutions to this graph (meaning when y equals 0 or when the graph crosses the x-axis) are 4 and 5.
The only answer choice that has the solutions 4 and 5 when you factor it out is D.
Here's the proof:
[tex]x^{2} -9x + 20[/tex]
Factors of 20: - 5 & -4
Sums that add up to -9: -5 + (-4)
[tex]x^{2} -4x-5x+20[/tex]
(factor the first two terms and the last two terms separately)
[tex](x^{2}-4x)(-5x+20)[/tex]
[tex]x(x-4) -5(x-4)[/tex]
(x - 5) (x - 4)
Hope it helps (●'◡'●)
09:30 am - 4:30 pm minus 30 minutes?
Answer:
4:30
because 9:30 minus 4:30 = 5:00 and 5:00 minus 30 =4:30
help me guys, I really need your help
Answer:
The answer should be like this;
a) A-B
b) BUC
c) C-A
HAVE A NİCE DAY
Step-by-step explanation:
GREETİNGS FROM TURKEY ツ
find the h.c.f. if 84 and 72
Answer:
12
Step-by-step explanation:
First lets list all the factors of these numbers
72: 1,2 3,4,6,8,9,12,18,24,36,72
84: 1 , 2 , 3 ,4 , 6 , 7 , 12 , 14 , 21 , 28 , 42 , 84
Now lets find the biggest number that is a factor of both 84 and 72
as we can see the highest number that is the factor of both 84 and 72 is 12
12 is the hcf
Sam wants to build a unique pyramid bookend for his study. It's an oblique pyramid
with a right triangular base. The sides of the base are 3, 4, and 5 inches long. The
pyramid will fit exactly inside his bookshelf, which has a height of 18 inches. He
wishes to build the pyramid out of modeling clay. How many cubic inches of clay
does Sam need to buy?
36in^3
24in^3
62.8in^3
216in^3
Answer:
Volume of triangular pyramid = 36 inch³
Step-by-step explanation:
Given:
Sides of base triangle = 3, 4, 5 inches
Height of model = 18 inches
Find:
Volume of triangular pyramid
Computation:
Given base triangle is a right angle triangle
So,
Area of base = (1/2)(b)(h)
Area of base = (1/2)(3)(4)
Area of base = (1/2))(12)
Area of base = 6 inch²
Volume of triangular pyramid = (1/3)(Area of base)(Height of model)
Volume of triangular pyramid = (1/3)(6)(18)
Volume of triangular pyramid = 36 inch³
Write down the equation that could be a correct equation for linear regression prediction function?
If the question meant that we should write a linear prediction function ;
Answer:
y = bx + c
Step-by-step explanation:
The equation for a linear regression prediction function is stated in the form :
y = bx + c
Where ;
y = Predicted or dependent variable
b = slope Coefficient
c = The intercept value
x = predictor or independent variable
Therefore, the Linear function Given represents a simple linear model for one dependent variable, x
b : is the slope value of the equation, whuch represents a change in y per unit change in x
A tax form asks people to identify their age, annual income, number of dependents, and social security number. For each of these four variables, identify the scale of measurement that probably is used and identify whether the variable is continuous or discrete.
Variable Nominal Ordinal Interval Ratio
Social security number
Annual income
Number of dependents
Variable Discrete Continuous
Social security number
Annual income
Number of dependents
Answer:
Types of variables:
Continuous variable include: income
Discrete variable include: number of dependents
Scale of measurement:
Nominal data include: Social security number
There is no ordinal data included
There is no interval data included
Ratio data include: Annual income,
Number of dependents.
Explanation:
Continuous variables are variables that are obtained by just counting, example: counting the number of times someone eats in a day.
Discrete variables are simply variables that are measured and are usually more precise than continuous variables, example: time, weight, length etc.
Nominal data are data types that are in the form of labels or names and do not have any particular order, example :social security number basically identifies a person and is not ranked or ordered in any way.
Ordinal data are data types that also in the form of names but with ranking and order.
Interval data are data types that rank and order data but with continuous measurement that may take on negative values, example measure of temperature.
Ratio data is same as interval data but does not take negative values, example we can not say that someone is -6 years old.
I need help with this problem.
Answer:
-4
Step-by-step explanation:
2t=-1-7
t=-8/2
t=-4
i am not sure also
Given that m∠abc=70° and m∠bcd=110°. Is it possible (consider all cases): Line AB intersects line CD?
The line AB and CD are parallel. Then it is impossible that the line AB intersects the line CD.
What are parallel lines?When the distance between the lines is constant, then the lines are called parallel lines. The lines do not intersect when they are separated from each other. And the slope of the lines is equal.
Given that ∠ABC = 70° and ∠BCD = 110°.
Then the line AB and the line CD makes the same angle with the line BC.
Hence, the line AB and CD are parallel.
Then it is impossible that the line AB intersects the line CD.
More about the parallel lines link is given below.
https://brainly.com/question/16701300
#SPJ1
True/False Questions - one attempt tor each question
If f is a decreasing function on an interval, then f'(x) > 0 on that interval.
True
False
Submit Question
Answer:
False
Step-by-step explanation:
f'(x) would be a negative number. Hence less than zero.
A philosophy professor assigns letter grades on a test according to the following scheme. A: Top 12% of scores B: Scores below the top 12% and above the bottom 57% C: Scores below the top 43% and above the bottom 19% D: Scores below the top 81% and above the bottom 5% F: Bottom 5% of scores Scores on the test are normally distributed with a mean of 66.5 and a standard deviation of 9.9. Find the minimum score required for an A grade. Round your answer to the nearest whole number, if necessary.
Answer:
The minimum score required for an A grade is 80.
Step-by-step explanation:
According to the Question,
Given That, A philosophy professor assigns letter grades on a test according to the following scheme.A: Top 12% of scores
B: Scores below the top 12% and above the bottom 57%
C: Scores below the top 43% and above the bottom 19%
D: Scores below the top 81% and above the bottom 5%
F: Bottom 5% of scores Scores on the test
And The normally distributed with a mean of 66.5 and a standard deviation of 9.9.
Now,
In a set with mean and standard deviation, the Z score of a measure X is given by Z = (X-μ)/σwe have μ=66.5 , σ=9.9
Find the minimum score required for an A grade.Top 12%, so at least the 100-12 = 88th percentile, which is the value of X when Z has a p-value of 0.88. So it is X when Z = 1.175.
⇒ Z = (X-μ)/σ
⇒ 1.175×9.9 = X-66.5
⇒ X=78.132
Rounding to the nearest whole number, the answer is 80.
The minimum score required for an A grade is 80.
what is the cost to drive from san francisco to los angeles (405 mi) if the cost of gasoline is $2.34/gal and the automobile gets 8.5 mi/L
Answer:
The cost is $ 29.5.
Step-by-step explanation:
distance = 405 miles
Cost = $ 2.34 /gal
Average = 8.5 miles per litre
So, the amount of gasoline to travel for 405miles
= 405/8.5 = 47.65 liter
1 gal = 3.785 liters
So,
47.65 liter = 47.65 / 3.785 = 12.6 gal
So, the cots is
= $ 2.34 x 12.6 = $29.5
Jen recently rode her bicycle to visit her friend who lives 6 miles away. On her way there, her average speed was 8 miles per hour faster than on her way home. If jen
spent a total of 2 hours bicycling find the two rates.
the answer is in the picture above
1. Suppose half of all newborns are girls and half are boys. Hospital A, a large city hospital, records an average of 50 births a day. Hospital B, a small, rural hospital, records an average of 10 births a day. On a particular day, which hospital is less likely to record 80% or more female births?
Answer:
5%
Step-by-step explanation:
Hospital A (with 50 births a day), because the more births you see, the closer the proportions will be to 0.5.
Hospital B (with 10 births a day), because with fewer births there will be less variability.
The two hospitals are equally likely to record such an event, because the probability of a boy does not depend on the number of births
Two hospitals have an equal chance of recording such an event.
What is probability?The area of mathematics known as probability deals with numerical representations of the likelihood that an event will occur or that a statement is true. An event's probability is a number between 0 and 1, where, roughly speaking, 0 denotes the event's impossibility and 1 denotes certainty.
Given
Hospital A (with 50 births per day), as the proportions will be closer to 0.5 the more births you see.
Hospital B (with 10 births per day), thus there will be less unpredictability with fewer births.
Due to the fact that the likelihood of a boy does not rely on the number of births, the two hospitals have an equal chance of recording such an event.
To learn more about probability refer to:
https://brainly.com/question/13604758
#SPJ2
What is the area of 4cm×7cm×8cm
Answer:
[tex]224cm^3\\[/tex]
Step-by-step explanation:
[tex]4cm*7cm*8cm=[/tex]
[tex]=224cm^3[/tex]
Hope this is helpful.
LWH=A
Plug in the numbers:
4*7*8=224^2
The area would be 224cm^2.
HELP PLEASE. Will give maximum points (100). I’m desperate. Will give brainiest for the correct answer, if wrong answer is given on purpose, I will report. Plz help.
Answer:
C, D, D.
Step-by-step explanation:
Problem 6)
We want to determine the equation of the graphed inequality.
First, let's determine the equation of the line for the inequality. We can see that it passes through the points (-2, 0) and (0, 2). Find the slope:
[tex]\displaystyle m=\frac{\Delta y}{\Delta x}=\frac{2-0}{0-(-2)}=\frac{2}{2}=1[/tex]
So, the slope of the line is one.
And since it passes through the point (0, 2), our y-intercept is two. Therefore, the equation of the line is:
[tex]y=x+2[/tex]
Next, notice that the shaded region is below the line. Also, the line itself is also shaded.
Since the shaded region is below the line, y is less than the graph of the line and since the line itself is shaded, our sign is less than or equal to.
Hence:
[tex]y \leq x + 2[/tex]
Our answer is C.
Problem 7)
We have the inequality:
[tex]-2x+8+5x>2x+1[/tex]
First, solve the inequality. Combine like terms:
[tex]3x+8>2x+1[/tex]
Subtract x from both sides:
[tex]x+8>1[/tex]
And subtract 8 from both sides:
[tex]x>-7[/tex]
Therefore, any value greater than -7 will satisfy the inequality.
Out of the choices, the only choice greater than -7 is -5.
So, our answer is D.
Problem 8)
We have the inequality:
[tex]5x+7\leq 8x-3+2x[/tex]
Again, solve the inequality. Combine like terms:
[tex]5x+7\leq 10x-3[/tex]
Subtract 5x from both sides:
[tex]7\leq 5x-3[/tex]
And add three to both sides:
[tex]10\leq 5x[/tex]
Divide both sides by five:
[tex]2\leq x[/tex]
Flip:
[tex]x\geq 2[/tex]
Therfore, any value greater than or equal to 2 will satisfy the inequality.
Out of the choices, the only choice greater than or equal to 2 is 2.
So, our answer is D.
You want to send postcards to 15 friends. In the shop there are only 3 kinds of postcards. In how many ways can you send the postcards, if
Answer:
455 ways
Step-by-step explanation:
Given
[tex]n = 15[/tex] --- friends
[tex]r = 3[/tex] -- available postcard kinds
Required
Ways of sending the cards
The question is an illustration of combination and the formula is:
[tex]^nC_r = \frac{n!}{(n - r)!r!}[/tex]
So, we have:
[tex]^{15}C_3 = \frac{15!}{(15 - 3)!3!}[/tex]
[tex]^{15}C_3 = \frac{15!}{12!*3!}[/tex]
Expand
[tex]^{15}C_3 = \frac{15*14*13*12!}{12!*3*2*1}[/tex]
[tex]^{15}C_3 = \frac{15*14*13}{3*2*1}[/tex]
[tex]^{15}C_3 = \frac{2730}{6}[/tex]
[tex]^{15}C_3 = 455[/tex]
Find the next number of the series 563, 647, 479, 812
Answer:
146
Step-by-step explanation:
next number is the last -666
A statistician calculates that 7% of Americans are vegetarians. If the statistician is correct, what is the probability that the proportion of vegetarians in a sample of 403 Americans would differ from the population proportion by more than 3%
Answer:
0.0182 = 1.82% probability that the proportion of vegetarians in a sample of 403 Americans would differ from the population proportion by more than 3%.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
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.
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]
A statistician calculates that 7% of Americans are vegetarians.
This means that [tex]p = 0.07[/tex]
Sample of 403 Americans
This means that [tex]n = 403[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.07[/tex]
[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.07*0.93}{403}} = 0.0127[/tex]
What is the probability that the proportion of vegetarians in a sample of 403 Americans would differ from the population proportion by more than 3%?
Proportion below 7 - 3 = 4% or above 7 + 3 = 10%. Since the normal distribution is symmetric, these probabilities are equal, which means that we find one of them, and multiply by 2.
Probability the proportion is below 4%
p-value of Z when X = 0.04.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.04 - 0.07}{0.0127}[/tex]
[tex]Z = -2.36[/tex]
[tex]Z = -2.36[/tex] has a p-value of 0.0091
2*0.0091 = 0.0182
0.0182 = 1.82% probability that the proportion of vegetarians in a sample of 403 Americans would differ from the population proportion by more than 3%.
A margin of error tells us how often the confidence interval estimates the parameter incorrectly. how often a confidence interval is correct. how accurate the statistic is when using it to estimate the parameter.
Answer:
how accurate the statistic is when using it to estimate the parameter.
Step-by-step explanation:
The margin of error may be referred to as a range or interval around a calculated statistic. The margin of error usually employed when calculating the confidence interval, will give a certain range of value within the sample statistic. This is sample statistic and margin is used to estimate the parameter albeit a certain percentage or proportion within the sample statistic. This provides the accuracy level at which the statistic will estimate the parameter.
Margin of Error :
Margin of Error = Zcritical * σ/√n ; OR
Margin of Error = Tcritical * s/√n
Where ;
σ = population standard deviation
s = sample standard deviation
