Let:
x be the liters of 20% acid solution.
y be the liters of pure acid solution.
To find x and y, follow the steps below.
Step 01: Write an equation for the number of liters.
The number of liters of the solution is 44, which is the sum of x and y.
[tex]x+y=44[/tex]Step 02: Isolate y in the equation above.
To do it, subtract x from both sides.
[tex]\begin{gathered} x+y-x=44-x \\ y=44-x \end{gathered}[/tex]Step 03: Write an equation that expresses the total of acid.
The total of acid is 0.4*44, which is equal to 1y plus 0.2x.
[tex]\begin{gathered} 0.4\cdot44=1\cdot y+0.2\cdot x \\ 17.6=y+0.2x \end{gathered}[/tex]Step 04: Substitute y by 44 - x in the equation above and isolate x.
[tex]\begin{gathered} 17.6=44-x+0.2x \\ 17.6=44-0.8x \end{gathered}[/tex]To isolate x, subtract 44 from both sides.
[tex]\begin{gathered} 17.6-44=44-0.8x-44 \\ -26.4=-0.8x \\ \end{gathered}[/tex]Now, divide both sides by -0.8.
[tex]\begin{gathered} \frac{-26.4}{-0.8}=\frac{-0.8}{-0.8}x \\ 33=x \end{gathered}[/tex]Step 05: Use the equation from step 2 to find y.
[tex]\begin{gathered} y=44-x \\ y=44-33 \\ y=11 \end{gathered}[/tex]Answer:
x is the liters of 20% acid solution = 33 L.
y is the liters of pure acid solution = 11 L.
a circle with radius 12 mm is rotated around a diameter what is the volume of the solid formed
We know that the radius of the sphere will be equal to the radius of the circle:
Since the equation for the volume of the sphere is:
[tex]V=\frac{4}{3}\pi r^3[/tex]where r is the radius
r = 12 mm
and
π = 3.1416
We can replace it:
[tex]\begin{gathered} V=\frac{4}{3}\pi r^3 \\ \downarrow \\ V=\frac{4}{3}\pi\cdot(12\operatorname{mm})^3 \\ \downarrow\text{ since}(12\operatorname{mm})^3=1728\operatorname{mm}^3 \\ V=\frac{4}{3}\pi\cdot1728\operatorname{mm}^3 \\ \downarrow\text{ since }\frac{4}{3}\cdot1728=2304 \\ V=2304\pi\operatorname{mm}^3 \\ \downarrow\text{ since }\pi=3.1416 \\ V=7238.2\operatorname{mm}^3 \end{gathered}[/tex]AnswerThen, the volume is given by
2304π mm³
or
7238.2 mm³
Gabriella is a 11 years younger than Mikal the sum of their ages is 51 what is mikhails age
Answer:
30
Step-by-step explanation:
11 plus 30 is 51 therefor your sum is 30
16. - 2y +5=-1Is 3 the solution?17. 1.3m -5.6 = -3Is-2 the solution?
To find out if a certain value of the variable is the solution of the equation we plug this value into the equation:
[tex]\begin{gathered} 1.3(-2)-5.6=-3 \\ -2.6-5.6=-3 \\ -8.2=-3 \end{gathered}[/tex]Since the last line is not true, then we conclude that -2 IS NOT the solution.
A school band has 75 members. The band enters a band competiton at a rival school.1.there are $200 entrance fee each band pluse a $25 entrance fee for each drill team. The competion. has a total of 32 bands and 25 drill teams. write and evaluate an expresion for the total amount of money collected from entrance fees.
The expression that would describe the problem is
200x +25y = M
where x is the number of band
y is the number of drill teams and
M is the total money collected.
If there are 32 bands and 25 drill team, the total money collected ,M woul d be:
M = 200x + 25 y
M = 200 (32) + 25 (25)
M= 6400 + 625
M = $7025
ANSWER:
M = 200x + 25y
M = $ 7025
y=0.5x+3; what is the slope?
The given equation,
[tex]y=0.5x+3[/tex]Comparing it with the slope intercept equation
[tex]y=mx+c[/tex]where m is the slope.
Thus the slope is m=0.5.
Let and y be whole-number variables such that y is the greatest whole number less than or equal to the table below lists some valuesfor and y.xy79411 513 6Which of the following statements is true?A. y changes by a constant amount when r changes by 2.OB. z changes by a constant amount when y changes by 1.C. y changes by a constant amount when changes by 1.D. 2 changes by a constant amount when y changes by 2.
we have
Verify each statement
A -------> For (7,3) and (9,4) -----> x changes by 2 and y change by 1
(9,4) and (11,5) -------> x changes by 2 and y change by 1
(11,5) and (13,6) -----> x changes by 2 and y change by 1
option A is true
B ----> option B is true
C -----> is not true
D ----> (7,3) and (11,5) ------> y changes by 2 and x changes by 4
(9,4) and (13,6) ----> y changes by 2 and x changes by 4
option D is true
step 2
Verify A, B and D
For x=14 ------> y=7
For x=16 -------> y=8
For x=18 ------> y=9
the answer must be option AI’m not sure why I keep getting this question wrong?
The value of (3x + 27)/8x when x = 3 is $1.50. That is it costs $1.50 to make 3 dozens cookies (option C)
Explanation:[tex]\begin{gathered} \text{The cost model for making x dozens of cookies:} \\ \frac{3x\text{ + 27}}{8x} \end{gathered}[/tex][tex]\begin{gathered} \text{when x = 3, we substitute x with 3} \\ \frac{3x\text{ + 27}}{8x}\text{ = }\frac{3(3)\text{ + 27}}{8(3)} \\ =\text{ }\frac{\text{9 + 27}}{24} \\ =\text{ }\frac{36}{24}=\frac{3}{2} \\ =\text{ }1.50 \end{gathered}[/tex]Since the cost we got is for 3 dozens of cookies, we say the cost for making 3 dozens of cookies is $1.50
The value of (3x + 27)/8x when x = 3 is $1.50. That is it costs $1.50 to make 3 dozens cookies (option C)
X + 5y = 8, -x + 2y = -1
x+5y=8
-x+2y=-1 => x=2y+1
(2y+1)+5y=8 => 7y=7 => y=1 => x=3
The answer is x=3 and y=1
Rearrange the equation so r is the independent variable q-10=6(r+1)
find the real solution(s), if any, of the system by examining the graph
Given:
[tex]\begin{gathered} -6x-3y=18\ldots\ldots\ldots(1) \\ \frac{x^{2}}{9}+\frac{y^{2}}{36}=1\ldots\ldots\ldots\ldots(2) \end{gathered}[/tex]Let us consider the equation (1),
[tex]\begin{gathered} -6x-3y=18 \\ -2x-y=6 \\ -y=2x+6 \\ y=-(2x+6)\ldots\ldots\ldots(3) \end{gathered}[/tex]Substitute equation (3) in (2), we get
[tex]\begin{gathered} \frac{x^2}{9}+\frac{(-(2x+6))^2_{}}{36}=1 \\ \frac{4x^2}{36}+\frac{4x^2+36+24x}{36}=1 \\ \frac{4x^2+4x^2+36+24x}{36}=1 \\ 8x^2+36+24x=36 \\ 8x^2+24x=0 \\ 8x(x+3)=0 \\ x=0,x=-3 \end{gathered}[/tex]Substitute x=0 and x=-3 in equation (3) we get,
[tex]\begin{gathered} y=-(2(0)+6) \\ =-6 \\ y=-(2(-3)+6) \\ =0 \end{gathered}[/tex]Hence, the solutions are, (0,-6) and (-3,0).
Let us verify this, by substituting (0,-6) and (-3,0) in equation (1), we get
For (0, -6),
[tex]\begin{gathered} -6(0)-3(-6)=18 \\ 18=18 \end{gathered}[/tex]For (-3, 0)
[tex]\begin{gathered} -6(-3)-3(0)=18 \\ 18=18 \end{gathered}[/tex]Hence, it is verified.
Can you please help me with the following equation
a(1.50) + b(0.50) = $7.00
Answer:
1.50a+0.50b=7.00
2.00ab=7.00
ab=3.1
Determine the area of the shaded sector. Use 3.14 for 7. Round your answer to the nearest tenth.
If the diameter is 26, the radius is 26/2 = 13
The area of a circle is (pi)(radius)^2 = 3.14(13)^2 = 3.14(169) = 530.66
A complete circle has 360 degrees
Half a circle is 180 degrees
So the shaded area is (360 - 180 - 120)/360 of the complete circle
Doing the operations: (360 - 180 - 120)/360 = 60/360 = 1/6 of the complete circle
If the complete circle area is 530.66, the shaded area is (1/6)(530.66) = 88.443
They ask for the result to be rounded to the nearest tenth, so the result would be 88.4
Answer: 88.4
2 A cognitive psychologist conducted a study of whether familiarity of words (X) predicts the time it takes (in seconds) to press a button indicating whether the word is singular or plural (I), with all participants being given the same words. Familiarity with these words was rated at a later time on a 7-point scale (with higher numbers indicating more farniliarity). The participants' scores were 6 2 5 3 7 Y 0.3 1.5 0.8 1.4 0.1 a Figure the Pearson correlation coefficient (25 pts.).
We will have the following:
*Firts: We have that the correlation coefficient is given by:
[tex]r=\frac{\sum ^n_{i=1}X_iY_i-\frac{1}{n}(\sum ^n_{i=1}X_i)(\sum ^n_{i=1}Y_i)}{\sqrt[]{\sum^n_{i=1}X^2_i-\frac{1}{n}(\sum^n_{i=1}X_i)^2}\sqrt[]{\sum ^n_{i=1}Y^2_i-\frac{1}{n}(\sum ^n_{i=1}Y_i)^2}}[/tex]*Second: We calculate the means, that is:
[tex]x_m=4.6[/tex]&
[tex]y_m=\text{0}.82[/tex]*Third: We calculate the sums:
[tex]\sum ^n_{i=1}X^2_i-\frac{1}{n}(\sum ^n_{i=1}X_i)^2=123-\frac{23^2}{5}=17.2[/tex][tex]\sum ^n_{i=1}Y^2_i-\frac{1}{n}(\sum ^n_{i=1}Y_i)^2=4.95-\frac{4.1^2}{5}=1.588[/tex][tex]\sum ^n_{i=1}X_iY_i-\frac{1}{n}(\sum ^n_{i=1}X_i)(\sum ^n_{i=1}Y_i)=13.7-\frac{23\cdot4.1}{5}=-5.16[/tex]Fourth: We replace the data:
[tex]r=\frac{-5.16}{\sqrt[]{17.2\cdot1.588}}\Rightarrow r=-0.987[/tex]Thus making the coefficient r = -0.987.
And this would be the scatterplot:
Last season, your favorite basketball teamwon 60 games. So far this season, yourfavorite basketball team has won 72 games.What is the percent change in the numberof games that your favorite team won fromlast season to this season?
In order to determine the percent change in the number of games, you first calculate the difference between the number of games won last season and current season.
current season = 70 games won
last season = 60 games won
70 - 60 = 10
next, you determine what is the associated percent of 10 games to 60 games from the last season. You proceed as follow:
(10/60)(100) = 16.66
that is, you calculate the quotient between increase of games won, the number of games won last season, and to the result you multiply by 100.
Hence, the increase in the percent of games won is of 16.66%
Use the following information to fill out the entire two-way table.At PRHS, there are 450 students in the 9th and 10th grade taking geometry, and one third ofthem are 9th graders. The students were surveyed on which unit from quarter 4 they liked best.65 students said that unit 5 was their favorite, but only 25 of them were 9th graders. Unit 8 wasthe most popular for 9th graders, with 50 of them saying it was their favorite. Unit 7 was themost popular with 10th graders, with 100 of them saying it was their favorite. Unit 6 and Unit 8were equally popular for 10th grade students. A total of 125 students sald that Unit 6 was theirfavorite.Answer ALL 3 of the following questions.1. What is the probability that a randomly selected student will be a 9th grade student OR astudent that preferred unit 7? Show your work or explain how you know. Leave it insimplified fraction form.2. What is the probability that a randomly selected student will be a 10th grade student whoalso prefers unit 8? Show your work or explain how you know. Leave it in simplifiedfraction form.3. Given the student prefers Unit 5, what is the probability the student is in the 10th grade?Show your work and explain how you know. Leave it in simplified fraction form.
Here, we want to calculate probabilities;
We have this as follows;
1) We want to calculate the probability that a randomly selected student is a 9th grader or a student that preferred unit 7
From here, we need the number of students who are 9th graders and students that prefer unit 7
From the question, we have it that 1/3 of the total students are 9th graders
So, for a total of 450, the number of 9th graders will be 1/3 * 450 = 150 students
Secondly we need the number of students that prefers unit 7
Let us try and complete the table as follows;
From the completed table, the numbers that like unit 7 are 130
So the probability we want to calculate is the sum of the two divided by 450
We have this as;
[tex]\frac{130+150}{450}\text{ = }\frac{280}{450}\text{ = }\frac{28}{45}[/tex]2) Here, we want to calculate the probability that a randomly selected student is a 10th grader who also prefers unit 8
From the table, we can see that the number of students who are 10th graders and also prefer unit 8 is 80
So, we have the probability as;
[tex]\frac{80}{450}\text{ = }\frac{8}{45}[/tex]3) Here, we want to calculate the probability that given that a student prefers unit 5, what is the probability that he is a 10th grader
We use the conditional probability value here
Where event A is the probability that student is a 10th grader, while event B is the probability that a student prefers unit 5
We have the probability as;
[tex]\begin{gathered} P(A|B)\text{ = }\frac{P(AnB)}{P(B)} \\ \\ P(\text{AnB) = }\frac{40}{450};\text{ P(B) = }\frac{65}{450} \\ \\ P(A|B)\text{ = }\frac{40}{65} \end{gathered}[/tex]what is the domian of the graph
answer:
2 ≤ x ≤ 5
step-by-step explanation:
at the end of the piece-wise function (the short line), the circles are closed.
closed circles = ≤ or ≥
open circles = < or >
immediately, c and d are out of the equation.
the domain refers to what the range of x-values is (bottom line) so let's look. we have (2,5) and (5,3)
the x-values of those are 2 and 5, with x in between/including them.
(if we were to find the range it would be 5 and 3, with x in between/including them)
so, 2 ≤ x ≤ 5. we use ≤ because it is not smaller than 2, and not bigger than five. using ≥ would be all numbers except in between 2 and 5.
Two-Variable inequalities from their graph. (0,0) and (4,3)
Points (0,0) (4,3)
Find slope m of line y= mx + b
m = 4/3. Positive
b= 0
Then equation is
y = (4/3)x
Now find inequality
y ≤ (4/3)x
Blue zone represents inequality searched
Answer is y≤ (4/3)x
John cleans 3 apartments in a weekend.The apartment have 6,5 and 7 rooms .If he earns $425 for the weekend,how much does she earn per room?
Given:
The number of departments =3.
The number of rooms is 6,5 and 7.
The total number of rooms = 6+5+7 =18 rooms.
The earning amount = $ 425.
The earing amount per room is
[tex]\frac{425}{18}=\text{23}.611[/tex]The earing amount per room is $23.61.
solve the system of linear equations by substitution x+4y=-1 and -3x-14=y
Explanation
We are given the equations below:
[tex]\begin{gathered} x+4y=-1(equation\text{ }1) \\ -3x-14=y(equation\text{ }2) \end{gathered}[/tex]We are required to solve the equations above simultaneously using substitution. Thus, we have:
[tex]\begin{gathered} From\text{ }equation\text{ }1, \\ x+4y=-1 \\ Make\text{ }x\text{ }the\text{ }subject \\ x=-1-4y(equation\text{ }3) \\ Substitute\text{ }for\text{ }x\text{ }into\text{ }equation\text{ }2 \\ Equation\text{ }2:-3x-14=y \\ \Rightarrow-3(-1-4y)-14=y \\ 3+12y-14=y \\ 12y-11=y \\ Collect\text{ }like\text{ }terms \\ -11=y-12y \\ -11=-11y \\ \frac{-11}{-11}=\frac{-11y}{-11} \\ y=1 \end{gathered}[/tex][tex]\begin{gathered} From\text{ }equation\text{ }3, \\ x=-1-4y \\ Substitute\text{ }the\text{ }value\text{ }of\text{ }y \\ x=-1-4(1) \\ x=-1-4 \\ x=-5 \end{gathered}[/tex]Hence, the answer is:
[tex]x=-5;y=1[/tex]I need to know if A and B are CORRECT and I need HELP WITH C
The sum of all angles of a triangle is always equal to 180°. Therefore, looking at triangle A we have 3 angles, 53°, 68°, and x. The sum of them will be 180:
a)
[tex]x+53+68=180[/tex]Now we solve it for x
[tex]\begin{gathered} x=180-53-68 \\ \\ x=59\degree \end{gathered}[/tex]b)
Same thing here, the angles are 46°, 71°, and x, the sum is equal to 180°:
[tex]\begin{gathered} x+46+71=180 \\ \\ x=180-46-71 \\ \\ x=63\degree \end{gathered}[/tex]c)
Now for C, we have the angles x, x again, and 24°, therefore the sum will be
[tex]\begin{gathered} x+x+24=180 \\ \\ 2x+24=180 \\ \\ 2x=180-24 \\ \\ 2x=156 \\ \\ x=\frac{156}{2} \\ \\ x=78\degree \end{gathered}[/tex]Final answers:
a) x = 59°
b) x = 63°
c) x = 78°
-56/6+10x1
please answer it is for a test
Answer:
-0.6 repeating
Step-by-step explanation:
-56/6 + 10 x 1
-56/6 + 10
-9.3 repeating + 10
-0.6 repeating
Answer:
i think 0.666666667
Step-by-step explanation:
If two lines intersect and one angle measures 25°, what are the measures of the other angles?1. 1252. 1553. 754. 25
When two lines intersect, four angles are created. Opposite angles are equal, therefore, we have two sets of angles with the same measure. Adjacent angles are supplementary.
By definition, supplementary angles add up to 180º. Since in our intersection we have an angle of 25º, the adjacent angles will be 180º minus 25º.
[tex]180-25=155[/tex]The measure of the other angles are 155º.
Compare each pair of rationals using a <, >, or =. 7. 3/4 ____ 7/10 8. -1.6 ____ 0.3 9. 2.8 ____ 5/2
EXPLANATION:
To know when a fraction is greater than another, the following procedure must be done, they must be multiplied by a cross and the result in whole number will determine which of the two is greater.
[tex]\begin{gathered} 7.\frac{3}{4}\text{ }>\frac{7}{10}=(3\times10)=30(4\times7)=28 \\ \\ \end{gathered}[/tex]7.You must first cross multiply the denominator of the first fraction with the number of the second fraction, then multiply the denominator of the second fraction with the numerator of the first fraction,So you will have the exact answer of which is the greatest.
[tex]8.\text{ -1.6 }<0.3[/tex]8.Every negative number that moves away from zero is always less than zero.
9.To compare or know which is greater if a decimal or a fraction we must divide the fraction between itself and this will give me a decimal, now if I can compare;
[tex]\begin{gathered} \frac{5}{2}=2.5_{} \\ \text{Now }compare\text{ the two decimals:} \\ 2.8>2.5; \end{gathered}[/tex]that is, 2.8 is greater than the fraction 5/2
I need help on number 10, the faster u do it the more stars I’ll give u!
Given the equation;
[tex]P=(l+w)[/tex]At;
[tex]\begin{gathered} l=14ft \\ w=9ft \end{gathered}[/tex]substituting the given values;
[tex]undefined[/tex]Will anyone be willing to help me with this? i’ll give 10 points
Only first table correctly represents y as a function of x where each value of x is mapped to a unique value of y.
What is a function?A function is defined from a set x to a set y where each element of x receives exactly one element of y. The set x is referred to as the function's domain, while the set y is referred to as the codomain of the function. A popular representation of this connection is y = f(x), which is pronounced "f of x."
Consider the first table:
Any value of x is mapped to a single value of y. Therefore first table represents a function.
Consider the second table:
For x = -50, there are 2 different values of y which are 50 and -50. Therefore second table does not represent a function.
Consider the third table:
For x = 21, there are 4 different values of y. Therefore third table does not represent a function.
Consider the fourth table:
For x = -25, there are 2 different values of y which are 30 and 20. Therefore fourth table does not represent a function.
To learn more about functions visit the below link:
https://brainly.com/question/22340031
#SPJ13
Find the unit price in cents per diaper for each of the brands shown below. Round to the nearest tenth of a cent.Brand A: 36 Diapers, $ 11.99 ? : ¢ per diaper Brand B: 50 Diapers, $11.49? : ¢ per diaper Note: Rounding to the nearest tenth of a cent is the same as rounding to the nearest thousandth of a dollar.Which is the better buy?
It is required that you find the unit price in cents per diaper.
To do this, convert the prices in dollars to cents by multiplying by 100.
[tex]\begin{gathered} \$11.99=11.99\times100\text{ cents} \\ =1199¢ \end{gathered}[/tex][tex]\begin{gathered} \$11.49=11.49\times100\text{ cents} \\ =1149¢ \end{gathered}[/tex]Next, divide the respective prices in cents by the corresponding number of diapers:
For brand A:
[tex]\frac{1199}{36}\approx33.3¢\text{ per diaper}[/tex]For brand B:
[tex]\frac{1149}{50}=22.98\approx23.0¢\text{ per diaper}[/tex]Next, notice that Brand B has a lower unit price. Hence, it is the better buy.
Brand B is the better buy,
Solve the equation 4x= 36
We are given the following equation
[tex]4x=36[/tex]Let us solve the equation for x
Divide both sides of the equation by 4 (this operation will cancel out the 4 on the left side)
[tex]\begin{gathered} 4x=36 \\ \frac{4x}{4}=\frac{36}{4} \\ x=\frac{36}{4} \\ x=9 \end{gathered}[/tex]Therefore, the value of x is 9
Answer: x = 9
Step-by-step explanation: 4 x 9 = 36
Which matrix represents the system of equations below? -12x-13y +132 = 15 7x-10 y– 3z = 11 7x+14y +5z =-5
The system of equations we have is:
[tex]\begin{gathered} -12x-13y+13z=15 \\ 7x-10y-3z=11 \\ 7x+14y+5x=-5 \end{gathered}[/tex]To write the matrix for the system of equations, we need to write only the coefficients of each variable in the matrix. Also, each column will belong to the coefficients of one variable, and each line will belong to each equation (the first line of the matrix will be for equation one, the second line for the second equation, and so on)
We start by writing the first equation into the matrix:
[tex]\begin{bmatrix}{-12} & {-13} & {13\text{ |15}} \\ {\square} & {\square} & \\ {\square} & {\square} & {\square}\end{bmatrix}[/tex]We write the coefficients of each variable x, y, and z, and then in the final column, we write the number that is after the equal symbol in this case 15 (also note that we put a line before 15 to separate the coefficients of the variables from the result of the equation).
Now we take the second equation of the system: 7x-10y-3z=11, and we write the coefficient number in the second line of the matrix:
[tex]\begin{bmatrix}{-12} & {-13} & {13\text{ |15}} \\ {7} & {-10} & {-3\text{ |11}} \\ {\square} & {\square} & {\square}\end{bmatrix}[/tex]And finally, we do the same with the third equation: 7x+14y+5z=-5, and we put the coefficients in order:
[tex]\begin{bmatrix}{-12} & {-13} & {13\text{ |15}} \\ {7} & {-10} & {-3\text{ |11}} \\ {7} & {14} & {5\text{ |-5}}\end{bmatrix}[/tex]According to psychologists, IQs are normally distributed, with a mean of 100 and a standard deviation of 18.a. What percentage of the population has IQs between 82 and 100?
To solve this question, we will have to find the Z score.
[tex]Z=\frac{x-\bar{x}}{s.d}[/tex]Where x is the value of the IQ
X-bar is the mean.
s.d is the standard deviation
[tex]\begin{gathered} Z_1=\frac{82-100}{18} \\ =-\frac{18}{18} \\ =-1 \end{gathered}[/tex][tex]Z_2=\frac{100-100}{18}[/tex][tex]\begin{gathered} Z_2=\frac{0}{18} \\ =0 \end{gathered}[/tex]The percentage of the population with IQs between 82 and 100 will be calculated thus:
[tex]\begin{gathered} P(-1-1) \\ =0.5-0.1587 \\ =0.34134 \\ \text{The percentage is}\colon \\ =0.34134\times100=34.134\text{ \%} \end{gathered}[/tex]9. A gallon of lemonade calls for 2 scoops of sugar. If you want to make 5 gallons, how much sugar should you put in? (2 pts)
Answer:10
Step-by-step explanation: if you need 2 for 1 gallon multiply it by 5
you have 1 gallon with 2 scoops
2 for 5 gallons gives you 10 scoops total for 5 gallons