Answer:
a) 8:3, b) no formula is there, c) 30
Step-by-step explanation:
because 200/75=8:3
because there formula being obtained
because 300/24=12.5
375/12.5=30
A statistics professor plans classes so carefully that the lengths of her classes are uniformly distributed between 47.0 and 57.0 minutes. Find the probability that a given class period runs between 51.25 and 51.5 minutes.
Answer:
0.025 = 2.5% probability that a given class period runs between 51.25 and 51.5 minutes.
Step-by-step explanation:
Uniform probability distribution:
An uniform distribution has two bounds, a and b.
The probability of finding a value between c and d is:
[tex]P(c \leq X \leq d) = \frac{d - c}{b - a}[/tex]
Uniformly distributed between 47.0 and 57.0 minutes.
This means that [tex]a = 47, b = 57[/tex]
Find the probability that a given class period runs between 51.25 and 51.5 minutes.
[tex]P(c \leq X \leq d) = \frac{51.5 - 51.25}{57 - 47} = 0.025[/tex]
0.025 = 2.5% probability that a given class period runs between 51.25 and 51.5 minutes.
Calculate the pH of a buffer solution made by mixing 300 mL of 0.2 M acetic acid, CH3COOH, and 200 mL of 0.3 M of its salt sodium acetate, CH3COONa, to make 500 mL of solution. Ka for CH3COOH = 1.76×10–5
Answer:
Approximately [tex]4.75[/tex].
Step-by-step explanation:
Remark: this approach make use of the fact that in the original solution, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] are equal.
[tex]{\rm CH_3COOH} \rightleftharpoons {\rm CH_3COO^{-}} + {\rm H^{+}}[/tex]
Since [tex]\rm CH_3COONa[/tex] is a salt soluble in water. Once in water, it would readily ionize to give [tex]\rm CH_3COO^{-}[/tex] and [tex]\rm Na^{+}[/tex] ions.
Assume that the [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] ions in this solution did not disintegrate at all. The solution would contain:
[tex]0.3\; \rm L \times 0.2\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COOH[/tex], and
[tex]0.06\; \rm mol[/tex] of [tex]\rm CH_3COO^{-}[/tex] from [tex]0.2\; \rm L \times 0.3\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COONa[/tex].
Accordingly, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] would be:
[tex]\begin{aligned} & c({\rm CH_3COOH}) \\ &= \frac{n({\rm CH_3COOH})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
[tex]\begin{aligned} & c({\rm CH_3COO^{-}}) \\ &= \frac{n({\rm CH_3COO^{-}})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
In other words, in this buffer solution, the initial concentration of the weak acid [tex]\rm CH_3COOH[/tex] is the same as that of its conjugate base, [tex]\rm CH_3COO^{-}[/tex].
Hence, once in equilibrium, the [tex]\rm pH[/tex] of this buffer solution would be the same as the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex].
Calculate the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex] from its [tex]{\rm K}_{a}[/tex]:
[tex]\begin{aligned} & {\rm pH}(\text{solution}) \\ &= {\rm pK}_{a} \\ &= -\log_{10}({\rm K}_{a}) \\ &= -\log_{10} (1.76 \times 10^{-5}) \\ &\approx 4.75\end{aligned}[/tex].
Applying the translation (x, y) - (x - 3, y + 7) maps the point (-4,7) onto the point
9
O A) (14, -7)
12
B) (7, -14)
15
C) (14, 7)
D) (-7, 14)
Answer: Choice D. (-7, 14)
Work Shown:
[tex](x,y) \to (x-3, y+7)\\\\(-4,7) \to (-4-3, 7+7)\\\\(-4,7) \to (-7, 14)\\\\[/tex]
The point has moved 3 units to the left and 7 units up. See the diagram below.
answer quick it's urgent
Expand : (5xy+7)(5xy-7)
Answer:
[tex](5xy + 7)(5xy-7) = 25x^2 y^2 - 49[/tex]
Step-by-step explanation:
[tex](a - b)(a +b ) = a^2 - b^2 \\\\From \ given \ expression \ a = 5xy \ , \ b = 7\\\\Therefore , (5xy + 7 )(5xy - 7 ) = ( 5xy)^2 - ( 7)^2 \\[/tex]
[tex]= 25x^2 y^2 - 49[/tex]
Answer:
25x²y² - 49
Step-by-step explanation:
We can do this by using the a+b formula:
(a+b)(a-b)= a² - b²
So,
(5xy+7)(5xy-7)
=(5xy)² - 7²
= 25x²y² - 49
Another way we can do this by expanding the algebraic expression:
(5xy+7)(5xy-7)
= 5xy(5xy-7) + 7(5xy-7)
= 25x²y² - 35xy + 35xy - 49
= 25x²y²- 49
The sum of 5 consecutive integers is 505. What is the second number in this sequence?
Answer:
The second number is 100.
Step-by-step explanation:
Let the first integer be x.
Then since the five integers are consecutive, the second integer will be (x + 1), the third (x + 2), fourth (x + 3), and the fifth (x + 4).
They total 505. Hence:
[tex]\displaystyle x+(x+1)+(x+2)+(x+3)+(x+4)=505[/tex]
Solve for x. Combine like terms:
[tex]5x+10=505[/tex]
Subtract 10 from both sides:
[tex]5x=495[/tex]
And divide both sides by five. Hence:
[tex]x=99[/tex]
Thus, our sequence is 99, 100, 101, 102, and 103.
The second number is 100.
If X is a normal random variable with mean 6 and standard deviation 2.0, then find the value x such that P(X > x) is equal to .7054. Group of answer choices5.28
5.46
4.92
7.28
Answer:
Step-by-step explanation:
If X is a normal random variable with a mean of 6 and a standard deviation of 3.0, then find the value x such that P(Z>x)is equal to .7054.
-----
Find the z-value with a right tail of 0.7054
z = invNorm(1-0.7054) = -0.5400
x = zs+u
x = -5400*3+6 = 4.38
Translate the sentence into an inequality. The product of w and 2 is less than 23.
Answer:
2w<23
Step-by-step explanation:
The product of w and 2 mean that w multiplied by 2
Please help me i will give you brainlest
Answer:
19. - 4/11
21. 14
Step-by-step explanation:
Im sorry but i can't solve 20
Using law of sines please show process!!!
Let the <C=x
We know in a triangle
☆Sum of angles=180°
[tex]\\ \sf\longmapsto 51+26+x=180[/tex]
[tex]\\ \sf\longmapsto 77+x=180[/tex]
[tex]\\ \sf\longmapsto x=180-77[/tex]
[tex]\\ \sf\longmapsto x=103°[/tex]
Please answer i need help please i will give you brainlest please
Answer:
14) 4x+10=8x-26 (corresponding angles are equal)
4x-8x=-26-10
-4x=-36
x= -36/-4= 9
x=9
15) perimeter of rectangle= 2(l+b)
2( l+ [tex]\frac{2l}{3}[/tex]) = 40m
2l+ [tex]\frac{4l}{3}[/tex] =40
Take LCM as 3
[tex]\frac{2l}{1}[/tex] * [tex]\frac{3}{3}[/tex] + [tex]\frac{4l}{3}[/tex] =40
[tex]\frac{6l+4l}{3}[/tex] = 40
[tex]\frac{10l}{3}[/tex] = 40
10l=40*3
10l = 120
l= 120/10 =12 cm
l=12cm
b= 2/3 *12 = 8cm
16) 2:3:4
It can be written as 2x+3x+4x
sum of angles of a triangle =180 degree
so 2x+3x+4x=180
9x=180
x=180/9=20 degree
1st angle=2x=2*20= 40 degree
2nd angle= 3x=3*20 =60 degree
3rd angle= 4x=4*20= 80 degree
17) sum of interior angles of a pentagon is 540 degree
so, 125+88+128+60+x=540 degree
401 +x= 540 degree
x=540-401= 139 degree
Hope this helps
Please mark me as brainliest
The product of -3x and (2x+5) is …
[tex]\huge{\boxed{\boxed{ Solution ⎇}}} \ [/tex]
[tex] - 3x \times (2x + 5) \\ = - 3x \times 2x + - 3x \times 5 \\ = - 6x ^{2} - 15x[/tex]
ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ ツ
꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐
[tex] \huge\boxed{\mathfrak{Answer}}[/tex]
[tex] - 3x \times (2x + 5) \\ = - 3x \times 2x + - 3x \times 5 \\ = - 6x ^{2} - 15x [/tex]
Answer ⟶ - 6x² - 15x
Draw a line representing the "rise" and a line representing the "run" of the line. State the slope of the line in simplest form.
Answer:
Slope = 2
Step-by-step explanation:
To find the slope of the line, you need to plot two points
My own two points will be: [tex](1,2)[/tex] and [tex](2,4)[/tex]
Now use the Slope-Formula to identify the slope of the line
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]
[tex]m=\frac{4-2}{2-1}[/tex]
[tex]m=\frac{2}{1}[/tex]
[tex]m=2[/tex]
so the slope of the line in simplest form will be 2.
Given that the area of a triangle ABC is 4.5 m², a=4, b=3, find two possible measures for angle C. Round your answer to the nearest tenth
Answer:
[tex]C = 48.6[/tex]
Step-by-step explanation:
Given
[tex]Area= 4.5m^2[/tex]
[tex]a =4[/tex]
[tex]b = 3[/tex]
Required
Find angle C
The area of the triangle will be calculated using:
[tex]Area = \frac{1}{2}ab \sin C[/tex]
So, we have:
[tex]4.5= \frac{1}{2} * 4 * 3 * \sin C[/tex]
[tex]4.5= 6 * \sin C[/tex]
Divide both sides by 6
[tex]0.75= \sin C[/tex]
Take arc sin of both sides
[tex]\sin^{-1}(0.75)= C[/tex]
[tex]48.6 = C[/tex]
[tex]C = 48.6[/tex]
please help to solve this in written format
Answer:
50 dozen total
Step-by-step explanation:
8/12 & 10/12.... average 9/12
11/12 - 9/12 =
2/12x = 100
2x = 1200
x = 600/12
50 dozen total
in the past year bill watch 64 movies that he thought were very good he watched 80 movies over the whole year of the movies he watched what percentage did he rate as very good
Answer:
he rate it 16%
Step-by-step explanation:
64-80\100=16
Which function represents the graph below?
Answer:
The answer is the third one below
Nina and Amy began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Nina took a test in English and earned a 71.8, and Amy took a test in Social Studies and earned a 60.7. Use the fact that all the students' test grades in the English class had a mean of 71.7 and a standard deviation of 11.7, and all the students' test grades in Social Studies had a mean of 60.6 and a standard deviation of 10.5 to answer the following questions.
a) Calculate the z-score for Nina's test grade.
b) Calculate the z-score for Amy's test grade.
c) Which person did relatively better?
i. Nina
ii. Amy
iii. They did equally well.
Answer:
a) [tex]Z = 0.0085[/tex]
b) [tex]Z = 0.0095[/tex]
c) ii. Amy
Step-by-step explanation:
Z-score:
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.
Question a:
Nina took a test in English and earned a 71.8. In the English class had a mean of 71.7 and a standard deviation of 11.7.
This means that [tex]X = 71.8, \mu = 71.7, \sigma = 11.7[/tex]
So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{71.8 - 71.7}{11.7}[/tex]
[tex]Z = 0.0085[/tex]
Question b:
Amy took a test in Social Studies and earned a 60.7. Students' test grades in Social Studies had a mean of 60.6 and a standard deviation of 10.5.
This means that [tex]X = 60.7, \mu = 60.6, \sigma = 10.5[/tex]
So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{60.7 - 60.6}{10.5}[/tex]
[tex]Z = 0.0095[/tex]
c) Which person did relatively better?
Amy had a higher z-score, so she did relatively better.
One angle of a triangle is twice as large as another. The measure of the third angle is 60° more than that of the smallest angle. Find the measure of each angle.
The measure of the smallest angle is º
Please help :)
Answer:
The measure of the smallest angle is 30º
Step-by-step explanation:
Let the angles be:
[tex]x \to[/tex] the first angle (the smallest)
[tex]y \to[/tex] the second angle
[tex]z \to[/tex] the third angle
So, we have:
[tex]y = 2x[/tex]
[tex]z=x + 60[/tex]
Required
Find x
The angles in a triangle is:
[tex]x + y +z = 180[/tex]
Substitute values for y and z
[tex]x + 2x +x + 60 = 180[/tex]
[tex]4x + 60 = 180[/tex]
Collect like terms
[tex]4x = 180-60[/tex]
[tex]4x = 120[/tex]
Divide by 4
[tex]x = 30[/tex]
The product of 2 integers is 72. One number is two less than five times the other. Which equation can be used?
Answer:
should be (5y-2)y = 72
Step-by-step explanation:
since the product of the two is 72, it's true that xy = 72. and it is also true that x is equal to five times y minus 2, so you can rewrite x as 5y-2. plug that in for x in the first equation, and you're set. hope this helps :)
Hello, please help me!!
Answer:
0.14
Step-by-step explanation:
P(A|B) asks for the probability of A, given that B has happened. This is equal to the probability of A and B over the probability of B (see picture)
Here, the question is asking if someone is taking the bus given that they are a senior.
The probability of someone being a senior and taking the bus is 5/100, or 0.05 . The probability of someone being a senior is 35/100, or 0.35
Our answer is then 0.05/0.35 = 1/7 = 0.14
A total of $20,000 is invested at an annual interest rate of 6%. No matter how many years this
money is invested, what is the best investment plan to earn the most money in the end?
Compounded continuously
Compounded daily
Compounded quarterly
Compounded monthly
PLS HELP please give an explanation if you don’t have one pls still give answer
An 80% confidence interval is (150, 170). What is the margin of error?
Answer:
10
Step-by-step explanation:
it is what it is
Give two examples of addition of two mixed numbers with different denominators
SHOW ALL STEPS
Answer:
First Example: 3 1/2 + 4 3/4, Second Example: 6 3/8 + 7 9/15
Extra Example: 8 4/20 + 3 5/10
Step-by-step explanation:
First Example:
1/2 + 3/4
1/2 is equal to 2/4 so it is now compatible to be added to 3/4.
2/4 + 3/4
= 5/4
Now for the mixed numbers since its 3 and 4, 3 + 4 = 7.
Final answer is 7 5/4.
Second Example:
3/8 + 9/15
9/15 can be reduced to 3/5
Now the equation is 3/8 + 3/5
= 15/40 + 24/40 is an equivalent equation
15/40 + 24/40
= 39/40
Now for the mixed numbers since its 6 and 7, 6 + 7 = 13
Final answer is 13 39/40.
I am going to include one last example just in case you need one:
Third Example:
4/20 + 5/10
We can reduce these to
1/5 + 1/2
= 2/10 + 5/10 is the equivalent equation
2/10 + 5/10
= 7/10
Now for the mixed numbers since its 8 and 3, 8 + 3 = 11.
Final answer is 11 7/10.
I Hope this helps!
The Statistical Abstract of the United States published by the U.S. Census Bureau reports that the average annual consumption of fresh fruit per person is 99.9 pounds. The standard deviation of fresh fruit consumption is about 30 pounds. Suppose a researcher took a random sample of 38 people and had them keep a record of the fresh fruit they ate for one year.
Appendix A Statistical Tables
(Round all z values to 2 decimal places. Round your answers to 4 decimal places.)
a. What is the probability that the sample average would be less than 90 pounds?
p =
b. What is the probability that the sample average would be between 98 and 105 pounds?
p =
c. What is the probability that the sample average would be less than 112 pounds?
p =
d. What is the probability that the sample average would be between 93 and 96 pounds?
p =
Answer:
Hence,
a) The probability that the sample average would be less than 90 pounds is 0.0210.
b) The probability that the sample average would be between 98 and 105 pounds is 0.5045.
c) The probability that the sample average would be less than 112 pounds is 0.9935.
d) The probability that the sample average would be between 93 and 96 pounds is 0.1341.
Step-by-step explanation:
a) [tex]P(X < 90) = P(Z < (90 - 99.9) / (30\sqrt(38)))[/tex]
= P(Z < -2.03) = 0.0210
b )[tex]P(98 < x <105) = P((98 -99.9) / (30 \sqrt(38)) < Z < (105 -99.9) / (30 \sqrt(38)))[/tex]
= P(-0.39 < Z < 1.05) = 0.5045
c ) [tex]P(X < 112) = P(Z < (112 - 99.9) / (30\sqrt(38)))[/tex]
= P(Z < 2.49) = 0.9935
d )[tex]P(93 < x < 96) = P((93 -99.9) / (30 \sqrt(38)) < Z < (96 -99.9) / (30 \sqrt(38)))[/tex]
= P( -1.42 < Z < -0.8 )
= 0.2119 - 0.0778 = 0.1341
you count after 2. What is the number?
4. When this 3-digit number is rounded to the
nearest hundred, it rounds to 200. Rounded
to the nearest ten, this number rounds to
200. The sum of the digits of this number
is 19. What is the number?
Answer:
I think the answer is 100 because nothing greater than 200 if its rounded hope this helped if not sorry
Identify the transformation that occurs to create the graph of g(x). g(x)=f(x)-7
Answer:
g(x) is obtained by shift the function f(x) down 7 units by subtracting 7 units from f(x).
Step-by-step explanation:
We are given that
[tex]g(x)=f(x)-7[/tex]
We have to identify the transformation that occurs to create the graph of g(x).
To identify the transformation that occurs to create the graph of g(x)
We will subtract the 7 from f(x).
Let f(x) be any function
[tex]g(x)=f(x)-k[/tex]
It means g(x) obtained by shift the function f(x) down k units by subtracting k units from f(x).
Therefore, g(x) is obtained by shift the function f(x) down 7 units by subtracting 7 units from f(x).
Solve for X.
-6x + 14 < -28
AND 3x + 28 < 25
Answer:
1. -6x + 14 < -28
6x<42
x<7
2. 3x + 28 < 25
3x < -3
x<-1
Hope This Helps!!!
what is the measure of an angle if it is 120 less than 5 times its own complement
Answer:
The measure of the angle is 55º.
Step-by-step explanation:
Complement of angle x:
If two angles are complementary, the sum of their measures is of 90º. Thus, the complement of an angle x is 90 - x.
In this question:
Angle is 120 less than 5 times its own complement, so:
[tex]x = 5(90 - x) - 120[/tex]
We have to solve for x
[tex]x = 450 - 5x - 120[/tex]
[tex]6x = 330[/tex]
[tex]x = \frac{330}{6}[/tex]
[tex]x = 55[/tex]
The measure of the angle is 55º.
Two different formulas of an oxygenated motor fuel are being tested to study their road octane numbers. The variance of road octane number for formula 1 is σ12=1.5, and for formula 2 it is σ22=1.2. Two random samples of size n1=15 and n2=20 are tested, and the mean octane numbers observed are x¯1=89.0 fluid ounces and x¯2=92.2 fluid ounces. Assume normality.
a. Test the hypothesis that the formulations are equal versus the hypothesis that formulation 2 produces a higher mean road octane number than formulation 1. Calculate z0=
b. Calculate a 95% two-sided confidence interval on the mean difference road octane number.
Answer:
Step-by-step explanation:
a)
zo=(89.0-92.2)/sqrt((1.5/15)+(1.2/20))
zo=-8.00
p-value=0.0000
Reject the null hypothesis.
b)
95% confidence interval for difference
=(89-92.2)+/-1.96*sqrt((1.5/15)+(1.2/20))
=-3.2+/-0.78
=(-3.98, -2.42)