Answer:
-0.00411522633
Step-by-step explanation:
[tex]\int\limits^9_3 {\frac{1}{(x+21)\sqrt{x+22} } } \, dx[/tex]
Let y = x + 22 and dy = dx, so the integral becomes
[tex]\displaystyle \int_3^9 \frac{\mathrm dx}{(x+21)\sqrt{x+22}} = \int_{25}^{31} \frac{\mathrm dy}{(y-1)\sqrt{y}}[/tex]
Now let z = √y, so that z ² = y. Then 2z dz = dy, and the integral becomes
[tex]\displaystyle \int_3^9 \frac{\mathrm dx}{(x+21)\sqrt{x+22}} = \int_{\sqrt{25}}^{\sqrt{31}} \frac{2z}{(z^2-1)z} \\\\ = \int_5^{\sqrt{31}} \frac{2}{z^2-1}\,\mathrm dz[/tex]
Expand the integrand into partial fractions:
[tex]\dfrac{2}{z^2-1} = \dfrac1{z-1}-\dfrac1{z+1}[/tex]
Then we have
[tex]\displaystyle \int_3^9 \frac{\mathrm dx}{(x+21)\sqrt{x+22}} = \int_5^{\sqrt{31}}\left(\frac1{z-1}-\frac1{z+1}\right)\,\mathrm dz \\\\ = \left(\ln|z-1|-\ln|z+1|\right)\bigg|_5^{\sqrt{31}} \\\\ =\left[\ln\left|\frac{z-1}{z+1}\right|\right]\bigg|_5^{\sqrt{31}} \\\\ =\ln\left(\frac{\sqrt{31}-1}{\sqrt{31}+1}\right) - \ln\left(\frac{4}{6}\right) \\\\ =\ln\left(32-2\sqrt{31}\right) - \ln\left(\frac23\right) \\\\ =\boxed{\ln\left(48-3\sqrt{31}\right)}[/tex]
A research center project involved a survey of 851 Internet users. It provided a variety of statistics on Internet users. (a) The sample survey showed that 92% of respondents said the Internet has been a good thing for them personally. Develop a 95% confidence interval for the proportion of respondents who say the Internet has been a good thing for them personally. (Round your answers to four decimal places.)
Answer:
The answer is "(0.9193924 , 0.9206076)".
Step-by-step explanation:
[tex]\text{sample proportion}\ (SP) = 0.92\\\\\text{sample size}\ n = 851\\\\\text{Standard error} \ SE = \sqrt{\frac{(SP \times(1 - SP)}{n})}\\\\[/tex]
[tex]= \sqrt{\frac{(0.92 \times (0.08)}{851})}\\\\= \sqrt{\frac{0.0736}{851}}\\\\= \sqrt{8.648\times 10^{-5}}\\\\=0.00031[/tex]
[tex]\text{CI level is}\ 95\% \\\\\therefore\\\\ \alpha = 1 - 0.95 = 0.05\\\\\frac{\alpha}{2} = \frac{0.05}{2} = 0.025\\\\ Z_c = Z_{(\frac{\alpha}{2})} = 1.96[/tex]
Calculating the Margin of Error:
[tex]ME = z_{c} \times SE\\\\[/tex]
[tex]= 1.96 \times 0.00031\\\\ = 0.0006076[/tex]
[tex]CI = (SP - z*SE, SP + z*SE)[/tex]
[tex]= (0.92 - 1.96 * 0.00031 , 0.92 + 1.96 * 0.00031)\\\\ = (0.92 - 0.0006076 , 0.92 + 0.0006076)\\\\= (0.9193924 , 0.9206076)[/tex]
Martin writes down 4
numbers.
Their mean is 8.
The range is 6.
The largest value is 11.
There is no mode.
Write down the four
numbers.
Answer:
5, 7, 9, 11
or
5, 6, 10, 11.
Step-by-step explanation:
The mean is 8 so the total value of the 4 numbers = 4*8 = 32.
Range is 6 so largest number - smallest = 6
The largest value is 11 so the smallest is 11-6 = 5
The middle 2 numbers add up to 32-(11+5) = 32 - 16
= 16.
- and as there is no mode they must be 7 and 9
or 6 and 10.
If ABCD is dilated by a factor of 3 the coordinates of A would be
Answer:
A'=(-9, - 3)
Step-by-step explanation:
A' will be 3*(the coordinates of A), A'=(-9, - 3)
Coordinates of A' are given by (-9,-3).
What is Coordinates?Coordinates of a point suggest the position of that particular point in the Cartesian Plane.
If the coordinates of a point are (x,y) then x is the distance of the point from Y-axis and y is the distance from the X-axis.
Here in the given graph, we can see that the coordinates of A of quadrilateral ABCD are (-3,-1)
ABCD is dilated by a factor of 3.
So the coordinates of the A' which is the point A after dilating by 3 are given by the product of 3 and corresponding original coordinations.
Hence the coordinates of A' are = (3*(-3),3*(-1)) = (-9,-3)
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Ashley, Milan, and Carlos sent a total of 131 text messages over their cell phones during the weekend. Carlos sent 7 times as many messages as Ashley. Ashley sent 4 more messages than Milan. How many messages did they each send?
Answer:
Ashley= 15
Milan= 11
Carlos= 105
Step-by-step explanation:
Let, A, M and C denotes Ashley, Milan and Carlos respectively.
A+M+C= 131 (according to the question)
Here,
C= 7A
A= M+ 4
So, M= A - 4
Now,
A+M+C = 131
or, A+ A-4+ 7A = 131 (putting the values)
or, 9A - 4 = 131 (adding like terms i.e. A + A + 7A)
or, 9A = 131 + 4
or, 9A = 135
or, A = 135 / 9
So, A = 15
C= 7A = 7×15= 105
M= A-4 = 15 - 4 = 11
Subtract 750 -389 plzzz help
Players A and B play a basketball game in which they take turns shooting the ball, and the first player to make their shot wins. Player A has probability 2/3 of making each of her shots. Player B has probability 1/2 of making each of his shots. If Player A shoots first, what is the probability that she will win
Answer:
Player A has a probability 2/3 of making each of her shots, then she has a probability 1/3 of missing each shot.
Player B has a probability 1/2 of making each of his shots, then he also has a probability 1/2 of missing each shot.
Let's separate each case.
Let's define:
P(x) = probability of winning at the "x" shot.
Player A wins on the first shot.
Because she has a probability 2/3 of making each of her shots, the probability of winning at the first shot is
P(1) = 2/3
Now let's see the next case, player A wins at her second shot.
This means that first, she misses her first shot, with a probability of:
p₁ = 1/3
Player B must miss his shot, the probability is:
p₂ = 1/2
Now player A must make her shot, so the probability is:
p₃ = 2/3
The joint probability is the product of the individual probabilities, so we have:
P(2) = (1/3)*(1/2)*(2/3) = 1/9
Now we can see the pattern, for P(3) we have
A misses: p₁ = 1/3 (first shot of A)
B misses: p₂ = 1/2
A misses: p₃ = 1/3 (Second shot of A)
B misses: p₄ = 1/2
A makes the shot: p₅ = 2/3
P(3) = (1/3)*(1/2)*(1/3)*(1/2)*(2/3) = 1/54
We already can see the pattern.
P(n) = (1/3)^(n - 1)*(1/2)*(n - 1)*(2/3)
Player A has a probability P of winning, and we can write P as:
P = P(1) + P(2) + P(3) + ...
Then we will have:
P = 2/3 + 1/9 + 1/54 + 1/324 + ... ≈ 0.8
Determine the positive integer values of k for which the following polynomia
over the integers given: c^2 – 7c+ k
look at the image for the question
Answer:
3166.7
Step-by-step explanation:
V = πr²h
V = π * (12 km)² * 7 km
V ≈ 3166.7 km³
Hey there!
First, let's review the formula for finding a cylinder's volume.
Formula: [tex]\pi r^2h[/tex]
Our new equation would look like this: [tex]\pi[/tex] x [tex]12^{2}[/tex] x 7.
The original answer would be 3166.72539482, but the question states that it want it rounded to the nearest tenth. So, your answer would be 3166.7.
Hope this helps! Have a great day!
f=((-1,1),(1,-2),(3,-4)) g=((5,0),(-3,4),(1,1),(-4,1)) find (fg)(1)
Answer:
f(g(1)) = - 2
Step-by-step explanation:
Find g(1) then use the value obtained to find f(x)
g(1) = 1 ← value of y when x = 1 (1, 1 ) , then
f(1) = - 2 ← value of y when x = 1 (1, - 2 )
6. A car dealership would like to estimate the mean mpg of its new model car with 90% confidence. The population is normally distributed; however we are taking a sample of 25 cars with a sample mean of 96.52 and a sample standard deviation of 10.70. Calculate a 90% confidence interval for the population mean using this sample data.
Answer:
92.9997<[tex]\mu[/tex]<99.5203
Step-by-step explanation:
Using the formula for calculating the confidence interval expressed as:
CI = xbar ± Z * S/√n where;
xbar is the sample mean
Z is the z-score at 90% confidence interval
S is the sample standard deviation
n is the sample size
Given parameters
xbar = 96.52
Z at 90% CI = 1.645
S = 10.70.
n = 25
Required
90% confidence interval for the population mean using the sample data.
Substituting the given parameters into the formula, we will have;
CI = 96.52 ± (1.645 * 10.70/√25)
CI = 96.52 ± (1.645 * 10.70/5)
CI = 96.52 ± (1.645 * 2.14)
CI = 96.52 ± (3.5203)
CI = (96.52-3.5203, 96.52+3.5203)
CI = (92.9997, 99.5203)
Hence a 90% confidence interval for the population mean using this sample data is 92.9997<[tex]\mu[/tex]<99.5203
A restaurant is doing a special on burgers. If the home team get a sack, the next day, burgers will cost$1
Normally, they cost $3,99. If every fan who attended the game (86,047 people) buys a $1.00 burger, how™
money did the restaurant lose with this discount?
ans: 257,256.59
if it was sold for $3.99
it would have been 86,047 × $3.99 = 343,303.59 and it was sold for $1 instead so automatically it's $86,047
therefore
343, 303.59
-86, 047 which is equal to a loss of $257, 256.59
GIVING 15 POINTS PLS FAST
Drag the tiles to the boxes to form correct pairs.
Match each addition operation to the correct sum.
-24 8 + 30
131.87
28.98+(-52.22)
65
45%+39
-23.24
56.75 +75.12
Reset
Next
Next
Answer:
Hope this helps! All you needed to do was add and subtract. Go through the slides, I added the step by step explanation, as well as the final table which contains the answers.
The value of the expressions are:
24(5/9) +30(7/9) = 6(2/9)
45(2/9) +39(3/9) = 84(5/9)
28.98 + (-52.22) =-23.24
56.75 + 75.12 = 131.87
We have,
Expressions:
-24(5/9) +30(7/9)
Simplifying the fractions.
This can be written as,
= (-24 + 30) +(-5/9 + 7/9)
= 6 + 2/9
= 6(2/9)
45(2/9) +39(3/9)
= (45 + 39) + (2/9 + 3/9)
= 84 + 5/9
= 84(5/9)
28.98 + (-52.22)
= 28.98 - 52.22
= -23.24
56.75 + 75.12
= 131.87
Thus,
The value of the expressions are:
24(5/9) +30(7/9) = 6(2/9)
45(2/9) +39(3/9) = 84(5/9)
28.98 + (-52.22) =-23.24
56.75 + 75.12 = 131.87
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Help me please answer this, this will be my first grade for freshman year. The picture of the question is down below.
Answer:
D
Step-by-step explanation:
-0.81 is a high negative correlation, which means the y is decreasing with x increasing, which means y(the number of broken glass) decreases when x(amount of paper used) increased. So we can say that the toilet paper is surely helping.
make me brainly if you find it correct
evaluate the expression for -c-12=
Answer:
-10
Step-by-step explanation:
We can substitute c into the equation as -2.
[tex]-(-2) - 12[/tex]
Two negatives make a positive:
[tex]2-12[/tex]
And [tex]2 - 12 = -10[/tex].
Hope this helped!
Suppose that a random sample of 16 measures from a normally distributed population gives a sample mean of x=13.5 and a sample standard deviation of s=6. the null hypothesis is equal to 15 and the alternative hypothesis is not equal to 15. using hypothesis testing for t values do you reject the null hypothesis at alpha=.10 level of significance?
Answer:
Step-by-step explanation:
The summary of the statistics given include:
population mean [tex]\mu[/tex] = 15
sample mean [tex]\oerline x[/tex] = 13.5
sample size n = 16
standard deviation s = 6
The level of significance ∝ = 0.10
The null and the alternative hypothesis can be computed as follows:
[tex]\mathtt{H_o: \mu = 15} \\ \\ \mathtt{H_1 : \mu \neq 15}[/tex]
Since this test is two tailed, the t- test can be calculated by using the formula:
[tex]t = \dfrac{\overline x - \mu}{\dfrac{\sigma }{\sqrt{n}}}[/tex]
[tex]t = \dfrac{13.5 - 15}{\dfrac{6}{\sqrt{16}}}[/tex]
[tex]t = \dfrac{- 1.5}{\dfrac{6}{4}}[/tex]
[tex]t = \dfrac{- 1.5\times 4}{6}}[/tex]
[tex]t = \dfrac{- 6.0}{6}}[/tex]
t = - 1
degree of freedom = n - 1
degree of freedom = 16 - 1
degree of freedom = 15
From the standard normal t probability distribution table, the p value when t = -1 at 0.10 level of significance, the p - value = 0.3332
Decision Rule: We fail to reject the null hypothesis since the p-value is greater than the level of significance at 0.10
Conclusion: Therefore, we can conclude that there is insufficient evidence at the 0.10 level of significance to conclude that the population mean μ is different than 15.
Fuller bought 4 cantaloupes at the grocery store. Each cantaloupe weighed between 4.5 and 6.3 pounds. Fuller estimates a reasonable weight of all the cantaloupes to be 21.2 pounds.
Answer:
Step-by-step explanation:
3w + 2c = 32
4w + 3c = 44
Multiply the 1st equation by 4 and 2nd equation by 3, we get:
12w + 8 c = 128
12w + 9 c = 132
Subtracting the top equation from the bottom equation, we get: c = 4
Substituting c = 4 in any one of the above equations and solving, we get: w = 8
Therefore, weight of 2w + 1c = 2(8) + 4 = 20 pounds (Answer)
All 20 children at a party were given one cookie, and then some were given an additional cookie. If a total of
32 cookies were given out, how many children received an additional cookie?
8
O 10
О о о
O 12
o 14
Answer:
If there were 20 children at a party, and each were given one cookie, then a total of 20 cookies were given out.
However, this is not the case, as 32 cookies were given out. So, we can see that 32 - 20 children, or 12 children, received one additional cookie.
Let me know if this helps!
in the diagram, POS,QOT and UOR are straight lines. Find the value of y.
Answer:
y = 15°
Step-by-step explanation:
Since ∠QOR and ∠UOT are vertical, they are congruent so ∠UOT = 5y. Since POS is a straight line (which has a measure of 180°) and ∠POS = ∠POU + ∠UOT + ∠TOS, we can write:
5y + 5y + 2y = 180
12y = 180
y = 15°
I need help with these
Answer:
2. 20 oranges
3. 18 yellow tulips
4. 23 students
17. what is the value of x?
18. what is the value of z?
please help me fast!!
for x ,
8x + 10x = 180°
[sum of linear pair is equal to 180°]
or, 18x = 180°
or, x = 180/18
therefore, x = 10°……
for z,
10z =8x
[ being corresponding angles are equal ]
or, 10z = 8 × 10°
( replacing x by 10°)
or, 10z = 80°
or, z = 80/10
thus z = 8°…………
Last year, Rob set up the Road Runner Race for his school.
The race was 1,200 meters long and 188 people signed up to
run the race. 38 people did not show up to run. This year,
there will be 3 times as many runners as last year. How
many people will run the race this year?
Answer:
450 people
Step-by-step explanation:
The number of people running a race this year will be 450.
What is an expression?
Mathematical expression is the combination of numerical variables and operations denoted by addition, subtraction, multiplication, and division signs.
Mathematical symbols can be used to represent numbers (constants), variables, operations, functions, brackets, punctuation, and grouping. They can also be used to denote the logical syntax's operation order and other properties.
Given that last year, Rob set up the Road Runner Race for his school. The race was 1,200 meters long and 188 people signed up to run the race. 38 people did not show up to run. This year, there will be 3 times as many runners as last year.
The number of people running a race this year:-
Number = ( 188 - 38 ) x 3
Number = 150 x 3
Number = 450
Therefore, the number of people running a race this year will be 450.
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Layla is going to drive from her house to City A without stopping. Layla plans to drive
at a speed of 30 miles per hour and her house is 240 miles from City A. Write an
equation for D, in terms of t, representing Layla's distance from City A t hours after
leaving her house.
Answer:
D = 240 - 30t
Step-by-step explanation:
If the equation represents her distance from City A, we need to include 240 in the equation to represent the distance to the city.
Then, we need to subtract 30t from 240 in the equation because 30t represents how far she will have traveled in t hours.
So, D = 240 - 30t is the equation that will represent Layla's distance from the city.
I need help with this please if anyone know I will appreciate it
Answer:
290.44
Step-by-step explanation:
The whole figure area can be calculated by assuming that the whole floor is a complete square of 18.2 x 18.2 and subtracting the area of the rectangular cutout which is 10.2 x 4
Area of the the flooring=18.2 x 18.2 - (10.2*4)=290.44
Which of the following correctly shows the quotient of 80 divided by 5 ?
Answer:16
Step-by-step explanation:
Just divide 80 by 5 or skip count by fives.
How do you write 5.44 in words?
Answer:
five and forty-four hundredths
Step-by-step explanation:
Answer:
five point four four
Step-by-step explanation:
The heat evolved in calories per gram of a cement mixture is approximately normally distributed. The mean is thought to be 100, and the standard deviation is 2. You wish to test H0: μ = 100 versus H1: μ ≠ 100 with a sample of n = 9 specimens.
A. If the acceptance region is defined as 98.5 le x- 101.5, find the type I error probability alpha.
B. Find beta for the case where the true mean heat evolved is 103.
C. Find beta for the case where the true mean heat evolved is 105. This value of beta is smaller than the one found in part (b) above. Why?
Answer:
A.the type 1 error probability is [tex]\mathbf{\alpha = 0.0244 }[/tex]
B. β = 0.0122
C. β = 0.0000
Step-by-step explanation:
Given that:
Mean = 100
standard deviation = 2
sample size = 9
The null and the alternative hypothesis can be computed as follows:
[tex]\mathtt{H_o: \mu = 100}[/tex]
[tex]\mathtt{H_1: \mu \neq 100}[/tex]
A. If the acceptance region is defined as [tex]98.5 < \overline x > 101.5[/tex] , find the type I error probability [tex]\alpha[/tex] .
Assuming the critical region lies within [tex]\overline x < 98.5[/tex] or [tex]\overline x > 101.5[/tex], for a type 1 error to take place, then the sample average x will be within the critical region when the true mean heat evolved is [tex]\mu = 100[/tex]
∴
[tex]\mathtt{\alpha = P( type \ 1 \ error ) = P( reject \ H_o)}[/tex]
[tex]\mathtt{\alpha = P( \overline x < 98.5 ) + P( \overline x > 101.5 )}[/tex]
when [tex]\mu = 100[/tex]
[tex]\mathtt{\alpha = P \begin {pmatrix} \dfrac{\overline X - \mu}{\dfrac{\sigma}{\sqrt{n}}} < \dfrac{\overline 98.5 - 100}{\dfrac{2}{\sqrt{9}}} \end {pmatrix} + \begin {pmatrix}P(\dfrac{\overline X - \mu}{\dfrac{\sigma}{\sqrt{n}}} > \dfrac{101.5 - 100}{\dfrac{2}{\sqrt{9}}} \end {pmatrix} }[/tex]
[tex]\mathtt{\alpha = P ( Z < \dfrac{-1.5}{\dfrac{2}{3}} ) + P(Z > \dfrac{1.5}{\dfrac{2}{3}}) }[/tex]
[tex]\mathtt{\alpha = P ( Z <-2.25 ) + P(Z > 2.25) }[/tex]
[tex]\mathtt{\alpha = P ( Z <-2.25 ) +( 1- P(Z < 2.25) })[/tex]
From the standard normal distribution tables
[tex]\mathtt{\alpha = 0.0122+( 1- 0.9878) })[/tex]
[tex]\mathtt{\alpha = 0.0122+( 0.0122) })[/tex]
[tex]\mathbf{\alpha = 0.0244 }[/tex]
Thus, the type 1 error probability is [tex]\mathbf{\alpha = 0.0244 }[/tex]
B. Find beta for the case where the true mean heat evolved is 103.
The probability of type II error is represented by β. Type II error implies that we fail to reject null hypothesis [tex]\mathtt{H_o}[/tex]
Thus;
β = P( type II error) - P( fail to reject [tex]\mathtt{H_o}[/tex] )
∴
[tex]\mathtt{\beta = P(98.5 \leq \overline x \leq 101.5) }[/tex]
Given that [tex]\mu = 103[/tex]
[tex]\mathtt{\beta = P( \dfrac{98.5 -103}{\dfrac{2}{\sqrt{9}}} \leq \dfrac{\overline X - \mu}{\dfrac{\sigma}{n}} \leq \dfrac{101.5-103}{\dfrac{2}{\sqrt{9}}}) }[/tex]
[tex]\mathtt{\beta = P( \dfrac{-4.5}{\dfrac{2}{3}} \leq Z \leq \dfrac{-1.5}{\dfrac{2}{3}}) }[/tex]
[tex]\mathtt{\beta = P(-6.75 \leq Z \leq -2.25) }[/tex]
[tex]\mathtt{\beta = P(z< -2.25) - P(z < -6.75 )}[/tex]
From standard normal distribution table
β = 0.0122 - 0.0000
β = 0.0122
C. Find beta for the case where the true mean heat evolved is 105. This value of beta is smaller than the one found in part (b) above. Why?
[tex]\mathtt{\beta = P(98.5 \leq \overline x \leq 101.5) }[/tex]
Given that [tex]\mu = 105[/tex]
[tex]\mathtt{\beta = P( \dfrac{98.5 -105}{\dfrac{2}{\sqrt{9}}} \leq \dfrac{\overline X - \mu}{\dfrac{\sigma}{n}} \leq \dfrac{101.5-105}{\dfrac{2}{\sqrt{9}}}) }[/tex]
[tex]\mathtt{\beta = P( \dfrac{-6.5}{\dfrac{2}{3}} \leq Z \leq \dfrac{-3.5}{\dfrac{2}{3}}) }[/tex]
[tex]\mathtt{\beta = P(-9.75 \leq Z \leq -5.25) }[/tex]
[tex]\mathtt{\beta = P(z< -5.25) - P(z < -9.75 )}[/tex]
From standard normal distribution table
β = 0.0000 - 0.0000
β = 0.0000
The reason why the value of beta is smaller here is that since the difference between the value for the true mean and the hypothesized value increases, the probability of type II error decreases.
A tin of tennis balls costs $6.99, and each tin contains 4
tennis balls.
If the tennis balls were sold individually, then
approximately how much would one tennis ball cost?
$
Answer:
About $1.75 per tennis balls
Step-by-step explanation:
A tin of 4 tennis balls costs $6.99. We are asked to find the price of one tennis ball.
We need to find the unit price, or price per ball.
Divide the cost by the number of tennis balls.
cost / tennis balls
cost = $6.99
tennis balls = 4 tennis balls
$6.99 / 4 tennis balls
Divide 6.99 by 4.
$1.7475 / 1 tennis ball
Round to the nearest cent or hundredth. The 7 in the thousandth place tells us to round the 4 to a 5 in the hundredth place.
$1.75 / 1 tennis ball
It would cost approximately $1.75 for one tennis ball.
If f(x) = 3x-1 and g(x)= x+2 find (f-g) (x)
Answer:
2x-3
Step-by-step explanation:
f(x) = 3x-1
g(x)= x+2
(f-g) (x) = 3x-1 - (x+2)
Distribute the minus sign
= 3x-1 -x-2
Combine like terms
= 3x-x -1-2
=2x -3
Complete the function table