f(1) = 10
Explanation:Given f(x) = 3x + 7
To find f(1), replace x by 1 in the equation above
f(1) = 3(1) + 7
= 3 + 7
= 10
IF LA = LB and LB = LC, then LA = LC. What property has been illustrated? a. Transitive b. Substitutionc. Distributived. Reflexive
The transitive property states that if x = y and y = z, then x = z
Considering the given scenario, IF LA = LB and LB = LC, then LA = LC, by comparing this statement with the earlier statement, we can see that
LA = x
LB = y
LC = z
Thus, the property being illustrated is
a. Transitive
at 3:00 the temperature is 8°C the temperature increases 2 degrees each hour for the next 3 hours. what is the temperature at 6:00?
We know that at 3:00 the temperature is 8°C, and the temperature increases 2°C each hour for the next 3 hours.
This means that after 3 hours, the temperature will increase:
[tex]2^{\circ}C+2^{\circ}C+2^{\circ}C=6^{\circ}C[/tex]Thus, the temperature at 6:00 will be:
[tex]8^{\circ}C+6^{\circ}C=14^{\circ}C[/tex]Select the correct answer.What is the domain of the function f(x) = x + 3x + 5?A. all whole numbersB. all positive real numbersC. all integersD. all real numbersRasatWats the answer
The given function is:
[tex]f(x)=x+3x+5[/tex]The domain is the set of all x-values for which the function is defined.
We can observe in this function, we don't have any restrictions on the domain, since the function is defined for any real number.
So, the domain is all real numbers.
Answer: D.
please help me solve. blank I have 9 and blank 2 I have 5. blank 2 is correct but not blank 1.
We have that
[tex]\begin{gathered} 3\cdot\sqrt[]{45}=3\cdot(\sqrt[]{9\cdot5}) \\ =\text{ 3(}\sqrt[]{9}\cdot\sqrt[]{5}\text{)} \\ =\text{ 3(3 }\cdot\sqrt[]{5}) \\ =9\cdot\sqrt[]{5} \end{gathered}[/tex]So the answer is
[tex]9\cdot\sqrt[]{5}[/tex]Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the correct position in the answer box. Release your mouse button when the item is place. If you change your mind, drag the item to the trashcan. Click the trashcan to clear all your answers. Click on an item at the bottom of the problem. Click again to drop each statement in the appropriate spot in the flow chart for adding fractions.
Let's say we want to add 1/2 and 1/3. Since they both have different denominators, first we find the LCD:
[tex]\text{LCD}(2,3)=2\cdot3=6[/tex]Now that we have the LCD, we express the fractions with a common denominator:
[tex]\frac{1}{2}+\frac{1}{3}=\frac{3}{6}+\frac{2}{6}[/tex]Now that we have both fractions with the same denominator, we can add directly the numerators and keep the denominator:
[tex]\frac{3}{6}+\frac{2}{6}=\frac{5}{6}[/tex]We have that 1/2+1/3=5/6. Since 5/6 can't be reduced anymore, we have found the result.
To summarize, the algorithm to solve addition of fraction would be like this:
part 1- Selected Response
Which of the following linear equations
have a negative y- intercept? Circle all that
apply.
A. y = 6x
Cy=
-3x +2
2
E. y=
• X
3
B.y=-5 + 2x
D.y=-x+8
F.y=-5
Answer: B, C, D and F
Step-by-step explanation: The y-intercept of a linear equation is the point at which the line crosses the y-axis. The y-axis is the vertical axis on a graph, and it is the axis where the x-coordinate is always 0. To find the y-intercept of a linear equation, we can set the x-coordinate to 0 and solve for the y-coordinate.
For example, consider the linear equation y = 6x. If we set the x-coordinate to 0, we get the equation 0 = 6 * 0, which simplifies to 0 = 0. Therefore, the y-intercept of this equation is (0, 0).
On the other hand, consider the linear equation y = -3x + 2. If we set the x-coordinate to 0, we get the equation 0 = -3 * 0 + 2, which simplifies to 0 = 2. Therefore, the y-intercept of this equation is (0, -2).
In general, a linear equation will have a negative y-intercept if the constant term in the equation is negative. In this case, the linear equations that have a negative y-intercept are B, C, D, and F. Therefore, the correct answer is B, C, D, and F.
latethe average rate of change from x = -21 of the function below.x2²+5x-12find the change in y by evaluating theon at-2 and 1:✓mange in y isREF
The given function is:
[tex]f(x)=x^2+5x-12[/tex]At x = -2:
f(-2) = (-2)² + 5(-2) - 12
f(-2) = 4 - 10 - 12
f(-2) = -18
At x = 1
f(1) = (1)² + 5(1) - 12
f(1) = 1 + 5 - 12
f(1) = -6
The change in y = f(1) - f(-2)
The change in y = -6 - (-18)
The change in y = -6 + 18
The change in y = 12
11. Write ____ as a single radical using the smallest possible root.
Answer:
[tex]\sqrt[6]{n^{23}}[/tex]Explanation:
The given expression is
[tex]\sqrt{n^5}\sqrt[3]{n^4}[/tex]To simplify, we first need to write them in exponent form
[tex]n^{\frac{5}{2}}\cdot n^{\frac{4}{3}}[/tex]Now, we can add the exponents
[tex]\begin{gathered} n^{\frac{5}{2}}\cdot n^{\frac{4}{3}}=n^{\frac{5}{2}+\frac{4}{3}}=n^{\frac{23}{6}} \\ \\ Because \\ \frac{5}{2}+\frac{4}{3}=\frac{5(3)+2(4)}{2(3)}=\frac{15+8}{6}=\frac{23}{6} \end{gathered}[/tex]Finally, we can write the expression in radical form
[tex]n^{\frac{23}{6}}=\sqrt[6]{n^{23}}[/tex]Therefore, the answer is
[tex]\sqrt[6]{n^{23}}[/tex]help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me help me
Given:
Three numbers are 42, 90 and 144.
Required:
What is the highest common factor
Required:
We know the factors of 42
Answer: 42, 90 and 144.
Step-by-step explanation:
A store sells packages of candy for $52. Each packet cost $4 to make and contains $48 flavored gum and candy.Rolando knows how much each candy cost per pound and knows how many pounds of each candy are packed in each package. Let x represent the amount of gum per pound in each package and y represent the amount of candy per pound in each package.Use the following equation to complete the questions: x+y=180.75x+5.25y+4=52how many pounds of candy are in a box?what is the price per pound for a piece of candy?what does the term 0.75x represents in the second equation?
Let:
x be the amount of gum in pounds in each package.
y be the amount of candy in pounds in each package.
Each box or package cost $52: a packaging that cost $4 and $48 in gum and candy.
The amount of candy (in pounds) in each package is shown in the equation:
[tex]x+y=18[/tex]As this is the sum of the amount of gum x and the amount of candy y, we can say that each package has 18 pounds of candy and gum.
Then, the following equation,
[tex]0.75x+5.25y+4=52[/tex]seems to be the total cost, as it results in 52, that is the total cost of the box. There is also a term with value 4, that corresponds to the packaginf cost.
The other terms represent the cost of the gum (0.75 * x) and the candy (5.25 * y).
We can read from this equation that the price per pound of the gum is 0.75, because it is the factor that multiply the amount x to calculate the cost.
In the same way, we can say that 5.25 is the price per pound of the candy, as it is the factor that multiplies y.
Answers
How many pounds of candy are in a box? 18 pounds
What is the price per pound for a piece of candy? 5.25 $/lb
What does the term 0.75x represents in the second equation? The second equation represents the sum of all the costs (gum, candy and packaging cost). The term 0.75x represents the cost of the gum, as it multiplies the price of the gum per pound (0.74 $/lb) and the amount of gum (x, in lb/package).
could I get an explanation on what the answers are and why?
a) Given:
[tex]k(x)=-x-3[/tex]It is of the form, y=mx+c.
Comparing we get, m=-1. That is a negative slope.
So, the answer is
Line with a negative slope.
b) Given:
[tex]g(x)=-4x^2+1[/tex]Since the quadratic function and its sign of the leading term is negative.
So, the answer is,
Parabola oppening down.
C) Given:
[tex]f(x)=3[/tex]It is of the form, y=c.
Comparing we get, the y-intercept is c=3. It is parallel to the x-axis.
So, the answer is,
Horizontal line.
8 pounds of bananas cost $24. How much would 31 pounds cost
31 pounds cost $93
Explanation
you can easily solve this by using a rule of three.
Step 1
Let x represents the cost for 31 pounds,the proportion is
[tex]\frac{x}{31}[/tex]Now
[tex]\begin{gathered} 24\text{ usd}\rightarrow8\text{ Pounds} \\ \text{the proportion must be the same, then} \\ \frac{24}{8}=\frac{x}{31} \\ 3=\frac{x}{31} \\ \end{gathered}[/tex]Step 2
solve for x
[tex]\begin{gathered} 3=\frac{x}{31} \\ x=3\cdot31 \\ x=93 \end{gathered}[/tex]Hence, 31 pounds cost $93
I hope this helps you
Directoins: consider the leading coefficient of each polynomial function. what is the end behavior of the graph? can check using graphing calculator or Desmos.10. F(x) = 4×over 3 - 3x
Concept
We can find the degree of a polynomial by identifying the highest power of the variable that occurs in the polynomial. The term with the highest degree is called the leading term because it is usually written first. The coefficient of the leading term is called the leading coefficient.
From the function
[tex]f(x)=4x^3\text{ - 3x}[/tex]Therefore,
The leading coefficient = 4
The degree = 3
Next, the end behavior of the function
The end behavior of a polynomial function is the behavior of the graph of f(x) as x approaches positive infinity or negative infinity. So, the sign of the leading coefficient is sufficient to predict the end behavior of the function.
Interpretations:
As x tends to positive infinity, f(x) tend to positive infinity
As x tends to negative infinity, f(x) tend to positive infinity
What would be the angles for K, J, and L?
The given is a triangle. As we know that the sum of all the interior angles in a triangle is 180 degrees, we have,
[tex]\begin{gathered} 6x-5+x+8+2x-3=180 \\ 9x=180 \\ x=\frac{180}{9}=20 \end{gathered}[/tex]Therefore, the angles can be calculated as,
[tex]\begin{gathered} K=6\times20-5=115 \\ J=20+8=28 \\ L=2\times20-3=37 \end{gathered}[/tex]x - y + z = - 3x - y - z = - 35x - 5y + z = - 15Solution: _, _, _
Given -
x - y + z = -3
x - y - z = -3
5x - 5y + z = -15
To Find -
Solution =?
Step-by-Step Explanation -
x - y + z = -3 ........(1)
x - y - z = -3 ..........(2)
5x - 5y + z = -15 .........(3)
So, from equation 1:
z = -3 -x + y
Now, put the value of z in equation 2 and 3:
x - y - (-3 -x + y) = -3
2x - 2y = -6
x - y = -3 ........(4)
5x - 5y + (-3 -x + y) = -15
4x - 4y = -12
x - y = -3 ......(5)
Now, on subtracting equations (5) and (6):
x - y -(x - y) = -3 - (-3)
x - x + y - y = 3 - 3
0 = 0
So, The System of equations has infinitely many solutions
Final Answer -
Solution: infinitely many solutions
Beth had 1/3 hour to get ready for work.She spent 1/5 hour putting on makeup.How much time does Beth have left?Give your answer in simplest form.1 hourEnter
To find how much time Beth has left, substract the time she spends on make up to the time she had to get ready.
This means that you have to substract 1/5 hour, which is the time she spends in make up, to 1/3 hour which is the time she has to get ready. This is: 1/3-1/5.
Imagine that you spent certain time on doing any activity, then you have to substract that time you spent from the time you had to do all your activities and duties. That is exactly what happened with Beth, she had 1/3 hour, but she spent 1/5 on make up, she needs to substract that 1/5 hour spent to the total time she had to know how much time she has left.
This will be a substraction of not similar fractions, you solve it this way:
[tex]\begin{gathered} \frac{1}{3}-\frac{1}{5} \\ =\frac{1\cdot5-1\cdot3}{3\cdot5} \\ =\frac{5-3}{15} \\ =\frac{2}{15} \end{gathered}[/tex]Now, she has 2/15 hours left.
7. Triangle MNQ is similar to triangle MOP. N 30 cm 9 cm M 0 12 cm P M M 24 cm Find the length of NQ. O A. 9.6 cm O B. 15 cm O C. 60 cm O D. 22.5 cm Please help!!! :( It is due today !!!
If the triangles MNQ and MOP are similar, then you know that the corresponding sides are at the same ratio. Because of this property, we can determine that:
[tex]\frac{MN}{MO}=\frac{MQ}{MP}=\frac{NQ}{OP}[/tex]We know the measure of the corresponding sides MQ=12cm and MO=24cm, and the measure of the corresponding side to NQ, using these measures we can calculate NQ as follows:
[tex]\begin{gathered} \frac{MQ}{MO}=\frac{NQ}{OP} \\ \frac{12}{24}=\frac{x}{30} \\ 30(\frac{12}{24})=x \\ x=15 \end{gathered}[/tex]Side NQ measures 15 cm
The correct option is B.
Solve the equation. -2/3 (x - 7) = 1/6 (x + 1) - 3
Given:
[tex]\frac{-2}{3}(x-7)=\frac{1}{6}(x+1)-3[/tex]Solving it,
[tex]\begin{gathered} \frac{-2}{3}x+\frac{14}{3}=\frac{x}{6}+\frac{1}{6}-3 \\ \end{gathered}[/tex]Solving further,
[tex]\begin{gathered} \frac{-2}{3}x-\frac{x}{6}=\frac{1}{6}-3-\frac{14}{3} \\ \frac{-4x-x}{6}=\frac{1-18-28}{6} \\ \frac{-5x}{6}=\frac{-45}{6} \\ -5x=-45 \\ x=\frac{45}{5} \\ x=9 \end{gathered}[/tex]Therefore, the value of x = 9
Really need help solving this, having trouble with it. It is trigonometry and it is from my online ACT prep guide
Solution
For this case we have the following:
Statement True False
sin (60º)= sqrt(3)/2 X
cot (pi)= 1 X
cos (-240º)= 1/2 X
csc(3pi/4)= sqrt(2)/2 X
What is the volume of the triangular prism?3.2 cm length 6 cm height5.4 cm width A: 8.64 cmB: 17.28 cmC: 51.84 cmD: 103.68 cm
The volume of a prism can be calculated by multiplying the area of the base of the prism times its height:
[tex]V=A\cdot h[/tex]On the other hand, the area of the base of a triangle can be found by multiplying 1/2 times its base times its height (don't confuse the height of the triangle with the height of the prism):
[tex]A=\frac{1}{2}b\times h[/tex]Substitute the values for the base of the triangle and its height to find the area of the base. Then, substitute the result for the area and the value of the height of the prism to find the volume of the triangular prism.
If the base of the triangle has a length of 5.4cm, and its height is 3.2cm, then:
[tex]\begin{gathered} A=\frac{1}{2}\times5.4\operatorname{cm}\times3.2\operatorname{cm} \\ =8.64cm^2 \end{gathered}[/tex]If the height of the prism is 6cm, then its volume is:
[tex]\begin{gathered} V=8.64cm^2\times6\operatorname{cm} \\ =51.84cm^3 \end{gathered}[/tex]Therefore, the volume of the triangular prism, is:
[tex]51.84cm^3[/tex]A bag contains 31 coins, some dimes and some quarters. The total amount of money in the bag is $4.45. How many dimes and how many quarters are in the bag?_____dimes_____quarters
A bag contains 31 coins, some dimes and some quarters. The total amount of money in the bag is $4.45. How many dimes and how many quarters are in the bag?
_____dimes
_____quarters
we know that
1 quarter=$0.25
1 dime=$0.10
Let
x -----> the number of quarters
y ----> the number of dimes
we have that
x+y=31 ------> equation A
0.25x+0.10y=4.45 -----> equation B
Solve the system of equations
Isolate the variable x in equation A
x=31-y ------> equation C
Substitute equation C in equation B
so
0.25(31-y)+0.10y=4.45
solve for y
7.75-0.25y+0.10y=4.45
0.25y-0.10y=7.75-4.45
0.15y=3.30
y=22 dimes
Find the value of x
x=31-22
x=9 quarters
therefore
the answer is
22 dimes9 quartersWhat are the intercepts of the equation 18x - 9y + 3z = 18?1. (1, 0, 0), (0, 2, 0), (0, 0, 6)2.(1, 0, 0), (0, -2, 0), (0, 0, 6)3.(6, 0, 0), (0, 3, 0), (0, 0, 1)4.(6, 0, 0), (0, -3, 0), (0, 0, 1)
SOLUTION
Given the question in the image, the following are the solution steps to answer the question.
STEP 1: Write the given equation
[tex]18x-9y+3z=18[/tex]To get the intercepts, we pick a point and equate the others to zero and then solve for the point.
STEP 2: Get the values of x when y and z are zeroes
[tex]\begin{gathered} 18x-9y+3z=1,z) \\ 18x-9(0)+3(0)=18 \\ 18x-0+0=18,18x=18 \\ Divide\text{ both sides by 18} \\ \frac{18x}{18}=\frac{18}{18} \\ x=1 \\ (x,y,z)\Rightarrow(1,0,0) \end{gathered}[/tex]STEP 3: Get the values of y when x and z are zeroes
[tex]\begin{gathered} 18x-9y+3z=18_{} \\ \text{Let x and z be 0} \\ 18(0)-9y+3(0)=18 \\ 0-9y+0=18 \\ -9y=18 \\ Divide\text{ both sides by -9} \\ \frac{-9y}{-9}=\frac{18}{-9} \\ y=-2 \\ (x,y,z)\Rightarrow(0,-2,0) \end{gathered}[/tex]STEP 4: Get the value of z when x and y are zeroes
[tex]\begin{gathered} 18x-9y+3z=18_{} \\ \text{Let x and y be 0} \\ 18(0)-9(0)+3z=18 \\ 3z=18 \\ Divide\text{ both sides by 3} \\ \frac{3z}{3}=\frac{18}{3} \\ z=6 \\ (x,y,z)\Rightarrow(0,0,6) \end{gathered}[/tex]Hence, the intercepts are:
[tex](1,0,0),(0,-2,0),(0,0,6)[/tex]solving a tax rate or interest rate problem using a system ofDonna bought a desktop computer and a laptop computer. Before finance charges, the laptop cost $150 more than the desktop. She paid for the computersusing two different financing plans. For the desktop the interest rate was 7% per year, and for the laptop it was 9.5% per year. The total finance charges forone year were S303. How much did each computer cost before finance charges?Note that the ALEKS graphing calculator can be used to make computations easier.
Answer
Cost of desktop = $1750
Cost of laptop = $1900
Explanation:
Let the price of the desktop computer be x
Let the price of laptop computer be y
Laptop cost $150 more than desktop
Therefore, the cost of laptop y is given mathematically below
y= x + 150 ------------ equation 1
The interest rate of laptop is 9.5%
The interest rate of desktop is 7%
A sum of $303 was paid for the total financial charges
This statement can be represented mathematically as
0.07x + 0.095y = 303 ------------------ equation 2
Combine the two system of equations together and solve simultaneously
y = x + 150 ------------ equation 1
0.07x + 0.095y = 303 ---equation 2
Substitute the value of y in equation 2
0.07x + 0.095(x + 150 ) = 303
Open the parentheses
0.07x + 0.095x + 14.25 = 303
Collect the like terms
0.07x + 0.095x = 303 - 14.25
0.165x = 288.75
Divide both sides by 0.165
0.165x / 0.165 = 288.75 / 0.165
x = $1750
Find y
Since y = x + 150
x = 1750
y = 1750 + 150
y = $1900
Therefore, the cost of a desktop is $1750 and the cost of a laptop is $1900Answer
Are The Ratios 1:2 and 18:16 equivalent?
The ratios given are;
1: 2 and 18: 16
To know it the ratios are equivalent , simplify the second pair until you can nologer express it in its simplest form then compare it with the he
Hi, can you help me answer this question please, thank you!
Given:
Two populations
Sample Size (n₁) = 202
Success (x₁) = 122
Sample size (n₂) = 340
Success (x₂) = 220
Find: test statistic and p-value of this sample
Solution:
Based on the given data, we have two proportions here and its sample size is large. The test statistic that is appropriate for this would be Test of Two Proportions and the formula is:
[tex]z=\frac{p_1-p_2+cont\text{ }}{\sqrt[]{\frac{p(1-p)}{n_1}+\frac{p(1-p)_{}}{n_2}}}[/tex]in which,
[tex]p=\frac{x_1+x_2}{n_1+n_2}[/tex]Let's solve the value of p first. Let's plug in the given data that we have above.
[tex]p=\frac{122+220}{202+340}=\frac{342}{542}=\frac{171}{271}[/tex]Now that we have the value of p, let's calculate p₁ and p₂. Formula is:
[tex]\begin{gathered} p_1=\frac{x_1}{n_1}=\frac{122}{202}=\frac{61}{101} \\ p_2=\frac{x_2}{n_2}=\frac{220}{340}=\frac{11}{17} \end{gathered}[/tex]Lastly, let's calculate the value of cont or continuity correction. Formula is:
[tex]cont=\frac{F}{2}(\frac{1}{n_1}+\frac{1}{n_2})\text{ }[/tex]For our claim p₁ < p₂, our F = 1.
[tex]cont=\frac{1}{2}(\frac{1}{202}+\frac{1}{340})=0.0039458[/tex]Let's plug these values to the test of two proportions formula:
[tex]\begin{gathered} z=\frac{p_1-p_2+cont\text{ }}{\sqrt[]{\frac{p(1-p)}{n_1}+\frac{p(1-p)_{}}{n_2}}} \\ z=\frac{\frac{61}{101}-\frac{11}{17}+0.0039458}{\sqrt[]{\frac{\frac{171}{271}(1-\frac{171}{271})}{202}+\frac{\frac{171}{271}(1-\frac{171}{271})_{}}{340}}} \end{gathered}[/tex][tex]z=\frac{-0.03915259}{\sqrt[]{\frac{0.2328399668}{202}+\frac{0.2328399668}{340}}}=\frac{-0.03915259}{0.04286603008}\approx-0.913[/tex]Hence, the test statistic is -0.913.
The equivalent p-value for this is 0.1805.
The p-value is greater than α = 0.05.
Since p-value is greater than α, we fail to reject the null hypothesis.
What is the correct answer to 9+(-3)= ?
To solve the question given, we will follow the steps below:
Open the parenthesis
9+(-3)
= 9 - 3
=6
The correct answer is 6
Keishas teacher gives her the following information: • m,n,p, and q are all integers and p =/ 0 and q =/ 0 • A= m/q and B = n/pAnswer: A+B = mp + nq / pq, so the sum of a rational number and an irrational number is an irrational number A•B = mp + nq / pq, so the product of two rational number is a rational number A + B = mp + nq / pq, so the sum of two rational number is a rational number. A•B = mp + nq / pq , so the product of two irrational number is an irrational number
Let A and B be the following fractions:
[tex]\begin{gathered} A=\frac{m}{q} \\ B=\frac{n}{p} \\ p,q\ne0 \end{gathered}[/tex]if we add A and B, we get:
[tex]A+B=\frac{m}{q}+\frac{n}{p}=\frac{mp+nq}{pq}[/tex]therefore, the sum of two rational numbers is a rational number
Sally can paint a room in 4 hours while it takes Steve 8 hours to paint the same room. How long would it take them to paint the room if they worked together?
Sally paints a room in 4 hours, so in 1 hour she paints 1/4 of a room.
Steve paints a room in 8 hours, so in 1 hour she paints 1/8 of a room.
So,
1 hour -----> 1/4 + 1/8 of a room
x hour -----> 1 of a room
3. A business account was opened with $225,000earning 6.25% interest compounded yearly. Whatis the balance in the account after 3 years? Howmuch interest is earned after 3 years?
Answer:
Balance = 269,897.15
Interest earned 44,879.15
Explanation:
The compound interest formula is
[tex]A=P(1+r)^t[/tex]where P is the principal amount, is the interest rate, and t is the time interval.
Now in our case, we have
P = $225,000
r = 6.25%/100
t = 3 years
therefore, the final amount is
[tex]A=225,000(1+\frac{6.25}{100})^3[/tex][tex]\boxed{A=\$269,879.15}[/tex]which is the balance earned in 3 years.
The interest earned is the final amount minus the initial amount
[tex]\begin{gathered} I=A-P \\ I=\$269,879.15-\$225,000 \end{gathered}[/tex][tex]\boxed{I=\$44,879.15}[/tex]which is the interest earned in 3 years.
15 is 20% of what numberOA 3O B. 60O C 75O D. 300
c)75
Explanation
to figure out this, we can use a rule of three
so,
let x represents the unknown value(
[tex]\begin{gathered} if \\ 15\Rightarrow20\text{ \%} \\ \text{then} \\ x\Rightarrow100\text{ \%} \end{gathered}[/tex]make the proportion and solve for x
[tex]\begin{gathered} \frac{15}{20}=\frac{x}{100} \\ \text{cross multiply} \\ 15\cdot100=20\cdot x \\ 1500=20x \\ \frac{1500}{20}=x \\ 75=x \end{gathered}[/tex]so, the answer is
C)75
I hope this helps you