Data was collected on the amount of time that a random sample of 8 students spent studying for a test and the grades they earned on the test. A scatter plot and line of fit were created for the data.
scatter plot titled students' data, with points plotted at 1 comma 75, 2 comma 70, 2 comma 80, 2 comma 90, 3 comma 80, 3 comma 100, 4 comma 95, and 4 comma 100, and a line of fit drawn passing through the points 0 comma 60 and 2 comma 80
Find the y-intercept of the line of fit and explain its meaning in the context of the data.
5; for each additional hour a student studies, their grade is predicted to increase by 5% on the test
10; for each additional hour a student studies, their grade is predicted to increase by 10% on the test
60; a student who studies for 0 hours is predicted to earn 60% on the test
80; a student who studies for 0 hours is predicted to earn 80% on the test
The equatiοn οf the line οf best fit fοr this data-set is given as fοllοws:
y = 10x + 60.
Hοw tο οbtain the equatiοn fοr the line οf best fit?The slοpe-intercept definitiοn οf a linear functiοn is given as fοllοws:
y = mx + b.
In which the cοefficients are given as fοllοws:
m is the slοpe, representing the rate οf change οf the οutput οf the functiοn relative tο the input.
b is the y-intercept, representing the value assumed by the functiοn the input assumes a value οf zerο.
The functiοn gοes thrοugh pοint (0,60), hence the intercept b οf the line οf fit is given as fοllοws:
b = 60.
When x increases by 2, frοm 0 tο 2, y increases by 20, frοm 60 tο 80, hence the slοpe m is οbtained as fοllοws:
m = 20/2 = 10.
Hence the line οf fit is given as fοllοws:
y = 10x + 60.
Meaning that the third οptiοn is cοrrect.
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Complete question:
Data was cοllected οn the amοunt οf time that a randοm sample οf 8 students spent studying fοr a test and the grades they earned οn the test. A scatter plοt and line οf fit were created fοr the data.scatter plοt titled students' data, with pοints plοtted at 1 cοmma 75, 2 cοmma 70, 2 cοmma 80, 2 cοmma 90, 3 cοmma 80, 3 cοmma 100, 4 cοmma 95, and 4 cοmma 100, and a line οf fit drawn passing thrοugh the pοints 0 cοmma 60 and 2 cοmma 80
Determine the equatiοn οf the line οf fit.
y = 5x + 60
y = 5x + 80
y = 10x + 60
y = 10x + 80
Answer:
The equatiοn οf the line οf best fit fοr this data-set is given as fοllοws:
y = 10x + 60.
Step-by-step explanation:
If the area of a bookshelf is 216 in.² if the length of the bookshelf is 36 inches what is the width of the bookshelf
The width of the bookshelf will be 6 inches when the area and length are 216 in and 36 inches.
What is the width?
Width is a dimension of a geometrical figure that tells about the structure of the figure. In general, width is used to measure the object.
What is formulae of width?
Width is obtained by dividing area and length.
W=A/L
substitute values, 216/36= 6inches.
The width is gonna be 6 because all you have to do is divide 216 and 36
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help i don’t know how to solve number 11, please
Answer: 21, 32. 6, 12.
Step-by-step explanation:
10 + 3d = 43. 3d = 33. d = 11.
3 x [tex]r^{3}[/tex] = 24. [tex]r^{3}[/tex] = 8. r = 2.
Rewrite r=1.5 sin theta in rectangular form
The polar curve r = 1.5sinθ in rectangular form is x² + y² - 1.5y = 0
How to write the polar curve in rectangular form?Since we have the polar curve r = 1.5sinθ and we want to convert it to rectangular form, we proceed as follows
We know that in rectangular form the polar curve is
x = rcosθ (1) and y = rsinθ (2)x² + y² = r² (3)So, multiplying r = 1.5sinθ by r, have that
r = 1.5sinθ
r × r = r × 1.5sinθ
r² = 1.5rsinθ
Substituting this into equation (3), we have that
x² + y² = r² (3)
x² + y² = 1.5rsinθ (4)
From equation (2), y = rsinθ
So, substituting this into equation (4), we have that
x² + y² = 1.5rsinθ
x² + y² = 1.5y
x² + y² - 1.5y = 0
So, the rectangular form is x² + y² - 1.5y = 0
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is the given value a solution of the inequality t-7<10, t = 28
Answer:
28 is NOT a given solution to the equality
Step-by-step explanation:
For this inequality, we substitute 28 for t and see if the left side is less than the right side.
[tex]t - 7 < 10, t = 28\\(28) - 7 < 10\\21 < 10 \\False[/tex]
The statement is false, therefore the number provided is not a solution
a patient is purchasing acetaminophen 500 mg tablets over-the-counter and asks the pharmacist how many they can take. what is the maximum number of tablets the pharmacist will tell them they should take of this product per day?
8 is the maximum number of tablets the pharmacist will tell them they should take of this product per day.
According to FDA guidelines, the maximum daily dosage of acetaminophen for healthy adults should not exceed 4,000 milligrams. This equates to a maximum of eight 500 mg tablets per day. It's essential to remember that the recommended dosage may differ based on individual factors such as age, weight, and medical conditions. Therefore, it's crucial to consult with a healthcare provider or licensed pharmacist before taking any medication. Always follow the recommended dosage and avoid exceeding the daily limit to prevent potential health risks associated with acetaminophen overdose.
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Consider the equation − 2(x + 2) = x − 3(x + 1) − 1. Is it always true, sometimes true, or never true?
Answer: Always true.
Step-by-step explanation: Use algebra. They end up being the same statements, which means x could be whatever and the equation would still be true.
Show how to change 9^8/7 into a radical expression
Answer:
Rewrite the expression using the negative exponent rule b−n=1bn b - n = 1 b n . 1y98 1 y 9 8.
Step-by-step explanation:
What is the slope of the line through (–2,3) and (1,–3) in the standard (x,y) coordinate plane
The slope of the line through (-2,3) and (1,-3) is -2.
What is slope-intercept form?Y = mx + b, where m is the line's slope and b is the y-intercept, is the slope-intercept form of a linear equation (the point where the line intersects the y-axis). This form is helpful because, given a line's equation, it enables us to quickly determine the slope and y-intercept. By charting the y-intercept and utilising the slope to identify additional points on the line, we can also use this technique to graph a line. We can also create an equation for a line given its slope and y-intercept using this approach.
The slope of the line is given as:
slope = (y2 - y1) / (x2 - x1)
Substituting the value of the given coordinates we have:
slope = (-3 - 3) / (1 - (-2))
slope = -6 / 3
slope = -2
Hence, the slope of the line through (-2,3) and (1,-3) is -2.
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Find sin X pleaseeee
Answer:
sin(x) = 9/41
Step-by-step explanation:
Every person in a group of 1000 people has a 1% chance of being infected by a virus. The process of being infected is independent from person to person. Using random variables, write expressions for the following probabilities and solve them with R.
(a) The probability that exactly 10 people are infected.
(b) That probability that at least 16 people are infected.
(c) The probability that between 12 and 14 people are infected.
(d) The probability that someone is infected.
Every person in a group of 1000 people has a 1% chance of being infected by a virus. The process of being infected is independent from person to person. Using random variables, write expressions for the following probabilities and solve them with R(a) The probability that exactly 10 people are infected
Solution:
a)Let X be the number of people infected in a group of 1000 people.
Here, X follows a binomial distribution with n = 1000 and p = 0.01.
Then, P(X = 10) = dbinom {1000}{10} $ $(0.01)^{10}$ $(1-0.01)^{990}
Using R, the expression for the probability that exactly 10 people are infected is:
p1 <- dbinom(10, 1000, 0.01)Ans: p1
(b) That probability that at least 16 people are infected.
Let X be the number of people infected in a group of 1000 people.
Here, X follows a binomial distribution with n = 1000 and p = 0.01.
Then, P(X ≥ 16) = 1 - P(X ≤ 15) = 1 - $\sum\limits_{i=0}^{15}$ $ \dbinom {1000}{i} $ $(0.01)^i$ $(1-0.01)^{1000-i}$Using R, the expression for the probability that at least 16 people are infected is:
p2 <- 1-pbinom(15, 1000, 0.01)Ans: p2
c) The probability that between 12 and 14 people are infected
.Let X be the number of people infected in a group of 1000 people.
Here, X follows a binomial distribution with n = 1000 and p = 0.01
. Then, P(12 ≤ X ≤ 14) = $\sum\limits_{i=12}^{14}$ $ \dbinom {1000}{i} $ $(0.01)^i$ $(1-0.01)^{1000-i}$Using R, the expression for the probability that between 12 and 14 people are infected is:
p3 <- sum(dbinom(12:14, 1000, 0.01))Ans: p3
d) The probability that someone is infected
.Let X be the number of people infected in a group of 1000 people.
Here, X follows a binomial distribution with n = 1000 and p = 0.01.
Then, P(X ≥ 1) = 1 - P(X = 0) = 1 - $ \dbinom {1000}{0} $ $(0.01)^0$ $(1-0.01)^{1000-0}$Using R, the expression for the probability that someone is infected is:
p4 <- 1-dbinom(0, 1000, 0.01)Ans: p4
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Ian went to dinner last night and remembers leaving a 6.50 tip. The tip was 20% of the cost of dinner. What was the cost of dinner before tip?
Answer:
$32.50
Step-by-step explanation:
20% * y = 6.5 =>
y =6.5 ÷ 20% =
6.5 ÷ (20 ÷ 100) =
(100 × 6.5) ÷ 20 =
650 ÷ 20 =
32.5
Percentage of 20% of what number = 6.5?
20% × ? = 6.5
20% of 32.5 = 6.5
Jackson is making lemonade for a class party. He uses 3 tablespoons (tbsp. ) of lemonade mix for each 6 ounces of water. He wants to make 4 quarts of lemonade. How much lemonade mix does Jackson need?
A
2 tbsp. B
16 tbsp. C
32 tbsp. D
64 tbsp
As per the unitary method, Jackson needs 64 tablespoons of lemonade mix to make 4 quarts of lemonade. (option D).
First, we need to convert the 4 quarts of lemonade into ounces since we know the ratio in terms of ounces. One quart is equal to 32 ounces (8 oz per cup and 4 cups per quart). So, 4 quarts would be equal to 128 ounces (32 oz x 4).
Next, we need to determine how much lemonade mix is needed for every 6 ounces of water.
Therefore, the ratio of lemonade mix to water is 3 tablespoons/6 ounces.
Now that we have the ratio, we can use it to find out how much lemonade mix is needed for 128 ounces of water (4 quarts). We can set up a proportion using the ratio we just found:
3 tbsp / 6 oz = x tbsp / 128 oz
We want to solve for x, which represents the amount of lemonade mix needed for 128 ounces of water. To solve for x, we can cross-multiply and simplify:
3 tbsp x 128 oz = 6 oz x
384 tbsp oz = 6x
x = 64 tbsp
So the answer is D) 64 tbsp.
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a 13 foot ladder is leaning against a wall. if the top slips down the wall at a rate of 1.25 ft/s, how fast will the bottom of the ladder be moving away from the wall when the top is 12 feet above the ground?
The top of the ladder is 12 feet above the ground, the bottom of the ladder will be moving away from the wall at a rate of 0.096 ft/s.
The question is: a 13 foot ladder is leaning against a wall. If the top slips down the wall at a rate of 1.25 ft/s, how fast will the bottom of the ladder be moving away from the wall when the top is 12 feet above the ground?
To answer this question, we can use the concept of right triangle geometry. We know that when the top of the ladder is 12 feet above the ground, the bottom of the ladder is 13 feet away from the wall.
We can use the Pythagorean Theorem to calculate the hypotenuse of this right triangle, which is the total length of the ladder. This will allow us to calculate the rate at which the bottom of the ladder is moving away from the wall.
The Pythagorean Theorem states that
a^2 + b^2 = c^2,
where a and b are the lengths of the legs of a right triangle, and c is the length of the hypotenuse.
In this case, a is 12 and b is 13.
Therefore,
122 + 132 = c^2, or c^2 = 169.
Therefore, c = 13.04 feet.
This is the total length of the ladder.
We now have the total length of the ladder, so we can calculate the rate at which the bottom is moving away from the wall.
Since we know the top is moving at a rate of 1.25 ft/s, and the total length of the ladder is 13.04 feet, the bottom must be moving at a rate of (1.25/13.04) = 0.096 ft/s.
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PLSSSS HELP IF YOU TURLY KNOW THISSS
Answer:
8
Step-by-step explanation:
4c ÷ 2 x 2 c=8
4 x 8 ÷ 2 x 2
4 x 8 ÷ 4
You can cancel the 4’s or multiply 4 x 8 then divide by 4, which is 8 :)
Given:-
[tex] \tt \: c = 8[/tex][tex] \: [/tex]
[tex] \tt{4c ÷ ( 2 \times 2 ) ---eqⁿ}[/tex][tex] \: [/tex]
Solution:-
[tex] \tt \: 4c ÷ ( 2 \times 2 )[/tex][tex] \: [/tex]
now , put the given value of c = 8 in equation
[tex] \tt \: 4 ( 8 ) ÷ ( 2 \times 2 )[/tex][tex] \: [/tex]
[tex] \tt \: 32 ÷ 4[/tex][tex] \: [/tex]
[tex] \boxed{ \tt{ \pink{ \: \: 8 \: \: }}}[/tex][tex] \: [/tex]
━━━━━━━━━━━━━━━━━━
hope it helps ⸙
A rectangular photograph is 8 inches by 10 inches. It will be put into a rectangular frame that is 2 inches wide on all sides. What is the area of the photograph when it is put into the
frame?
Answer:
the area of the photograph when it is put into the frame is 80 square inches, and the area of the frame is 88 square inches.
Step-by-step explanation:
Answer: 36 inches(2)
Step-by-step explanation:
Compounds angles identities
Answer:
Compound angle identities are trigonometric identities that relate the trigonometric functions of the sum or difference of two angles to the trigonometric functions of the individual angles.
The main compound angle identities are:
1. sin(A ± B) = sin(A)cos(B) ± cos(A)sin(B)
2. cos(A ± B) = cos(A)cos(B) ∓ sin(A)sin(B)
3. tan(A ± B) = (tan(A) ± tan(B)) / (1 ∓ tan(A)tan(B))
where A and B are any two angles.
These identities can be used to simplify trigonometric expressions, solve trigonometric equations, and prove other trigonometric identities.
For example, we can use the compound angle identity for sin(A + B) to find sin(π/4 + π/6):
sin(π/4 + π/6) = sin(π/4)cos(π/6) + cos(π/4)sin(π/6)
sin(π/4 + π/6) = (√2/2)(√3/2) + (√2/2)(1/2)
sin(π/4 + π/6) = (√6 + √2) / 4
Compound angle identities are an important part of trigonometry and are used in various fields such as physics, engineering, and mathematics.
is the number of linearly independent columns in a matrix a equal to the number of linearly independent rows in a? why?
Yes, the number of linearly independent columns in a matrix A is equal to the number of linearly independent rows in A.
This is because the definition of linear independence states that no linear combination of a set of vectors can equal the zero vector, so if one set of vectors is linearly independent, the other set of vectors must also be linearly independent.
To explain further, the number of linearly independent vectors in a matrix A is determined by the rank of the matrix. The rank of a matrix is the number of linearly independent rows and columns in the matrix.
So if the rank of A is n, then the number of linearly independent columns and rows of A must be n. This is because if there are n linearly independent columns in the matrix, the number of linearly independent rows must also be n.
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Which expression is equivalent to the following complex fraction?
The expression that is equivalent to the following complex fraction is this: B. -2y + 5x/3x -2y.
What is an equivalent expression?An equivalent expression is one that produces the same result as the given one when simplified. To get the equivalent expression, we simply need to simplify the expression above and the one underneath.
After finding the lowest common multiples of the figures underneath and the ones above, the next thing to do will be to multiply by the numerators.
-2/x + 5/y = -2y + 5x
Also:
3/y - 2/x = 3x - 2y
So, option B is an equivalent expression of the complex fraction.
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Oliver ask 20 children's how they travel to school you are other reasonOliver ask 20 children's how they travel to school here are the reason walkOliver ask 20 children's how they travel to school here are the reason what three bicycle 2 calculate the percentage of the children who travel to school by bicycle
From the given information provided, the percentage of children who travel by bicycle is 15%.
According to the given information, out of 20 children, 3 of them travel to school by bicycle. To calculate the percentage of children who travel to school by bicycle, we need to divide the number of children who travel by bicycle by the total number of children and multiply by 100.
Percentage of children who travel to school by bicycle = (Number of children who travel by bicycle / Total number of children) x 100%
= (3/20) x 100%
= 15%
Therefore, the percentage of children who travel to school by bicycle is 15%.
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Find the perimeter of the triangle shown below.
:48
:96
:120
:160
12
20 H
16
Answer:
48
Step-by-step explanation:
[tex]perimeter = a + b + c \\ = 12 + 20 + 16 \\ = 48[/tex]
What is the volume of the composite figure?
A complex figure comprised of 2 rectangular prisms. Prism A has a length of 2 centimeters, a width of 5 centimeters, and a height of 6 centimeters. Prism B has a length of 8 centimeters, width of 3 centimeters, and height of 6 centimeters.
204 cm3
342 cm3
604 cm3
4,211 cm3
Answer:
its 204cm3
Step-by-step explanation:
2x5x6=60
8x3x6=144
144+60=204
hope this helps!
using traditional methods, it takes 101 101 hours to receive a basic flying license. a new license training method using computer aided instruction (cai) has been proposed. a researcher used the technique with 140 140 students and observed that they had a mean of 100 100 hours. assume the standard deviation is known to be 6 6 . a level of significance of 0.01 0.01 will be used to determine if the technique performs differently than the traditional method. is there sufficient evidence to support the claim that the technique performs differently than the traditional method? what is the conclusion?
In the following question, Yes, there is sufficient evidence to support the claim that the computer-aided instruction (CAI) technique performs differently than the traditional method.
To determine this, a two-tailed hypothesis test can be performed using the sample data given. The null hypothesis is that the computer-aided instruction technique has the same mean as the traditional method (101 hours). The alternative hypothesis is that the computer-aided instruction technique has a different mean than the traditional method (101 hours). With a sample mean of 100 hours, a sample size of 140 students, a known population standard deviation of 6 hours, and a level of significance of 0.01, the hypothesis test is conducted and results in a p-value of less than 0.01. This suggests that there is sufficient evidence to reject the null hypothesis and support the alternative hypothesis, that the computer-aided instruction technique performs differently than the traditional method. The conclusion is that the computer-aided instruction technique has a different mean than the traditional method.
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There is sufficient evidence to support the claim that the new license training method using computer-aided instruction performs differently than the traditional method. Therefore, the researcher can proceed with the new method.
Hypothesis testing is a technique used to make inferences about the population based on the sample data. It is divided into two types, one-tailed and two-tailed. A two-tailed test involves testing for the difference between the two population means, while a one-tailed test involves testing for a higher or lower population mean. A level of significance is predetermined to accept or reject the null hypothesis.
Given, using traditional methods, it takes 101 hours to receive a basic flying license. A new license training method using computer-aided instruction (CAI) has been proposed. A researcher used the technique with 140 students and observed that they had a mean of 100 hours. Assume the standard deviation is known to be 6.
We have to determine if there is sufficient evidence to support the claim that the technique performs differently than the traditional method at a level of significance of 0.01.
Null Hypothesis H₀: μ₁ = μ₂ (The new technique and traditional method do not perform differently.)
Alternate Hypothesis H₁: μ₁ ≠ μ₂ (The new technique and traditional method perform differently.)
The test statistic for testing the difference in two population means with known standard deviation is given by:
z = (x₁ - x₂) / (σ/√n)
Where,
x₁ = sample mean of the new technique
x₂ = sample mean of the traditional method
σ = known standard deviation
n = sample size
z = test statistic
z = (100 - 101) / (6 / √140)
z = -2.624
The corresponding p-value can be obtained from the Z-table.
p-value = P(z < -2.624) + P(z > 2.624)
p-value = 0.0088 + 0.0088
p-value = 0.0176
The level of significance α = 0.01
Since p-value < α, we can reject the null hypothesis.
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write a linear equation with a slope of -7
PLEASE HELP
find the equation of the line
using exact numbers
Answer: y = -3x + 7
Step-by-step explanation:
slope = -3
y intercept = 7
the ages of students at a university are normally distributed with a mean of 20. what percentage of the student body is at least 20 years old?
The percentage of the student body that is at least 20 years old is 50%.
The ages of students at a university are normally distributed with a mean of 20. To find the percentage of the student body that is at least 20 years old solution to the is as follows: As the Mean of ages of students at a university, μ = 20. Age is normally distributed so it will be divided into two groups Therefore, the mean age is equal to the median age. As the age is normally distributed, 50% of the population will have an age greater than or equal to 20 years old. Thus, the percentage of the student body that is at least 20 years old is 50%. Hence, the required percentage of the student body that is at least 20 years old is 50%.
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It takes jerry 3 hours to clean all the tank in his section. It take hart x hours to clean all the tanks in his section. If they work together they can clean the tanks in 1 hour. What fraction does Jerry get done in 1 hour
The amount or fraction of work Jerry gets done in 1 hour is 1/3 when it takes him 3 hours to clean all the tank in his section and it take Hart x hours to clean all the tanks in his section.
We know that it takes jerry 3 hours to clean all the tank in his section and it take Hart x hours to clean all the tanks in his section,
when they work together, they can clean the tanks in 1 hour.
now let work be - 1
therefore,
work x Jerry = work x Hart
1×3 = 1×x
3 = 1x
3 = x
therefore in 1 hour work done by Jerry will be 1/3.
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Consider the following equivalent resonance structures for the carbonate anion. Charges have not been shown.
What is the average formal charge on each oxygen atom?
answerable question reference
A -0.33
B -0.67
C -1
D 0.33
E 0.67
This is an example of resonance where all three structures contribute to the description of the anion and none of them are more accurate than the others. The sum of the formal charges for each of the resonance structures is equal to the net charge of the anion.
The carbonate anion can be represented by three equivalent resonance structures. These structures differ in the placement of electrons and the distribution of formal charges on the individual atoms. Structure B has a formal charge of -0.67 on the oxygen atom and a formal charge of 0.33 on the carbon atom.
Structure D has a formal charge of 0.33 on the oxygen atom and a formal charge of -0.67 on the carbon atom. Structure E has a formal charge of 0.67 on the oxygen atom and a formal charge of -0.67 on the carbon atom.
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Please Help Quickly ASAP Hurry ASAP
What is the value of θ for the acute angle in a right triangle?
sin(θ)=cos(44°)
Therefore, the value of θ for the acute angle in a right triangle is 46°.We can use the fact that the sine and cosine of complementary angles are equal to find θ.
To find the value of θ for the acute angle in a right triangle, we need to use one of the trigonometric ratios. In this case, we are given the sine of θ and the cosine of 44°. Recall that the sine of an angle θ is defined as the ratio of the opposite side to the hypotenuse in a right triangle:
sin(θ) = opposite / hypotenuse
And the cosine of an angle φ is defined as the ratio of the adjacent side to the hypotenuse:
cos(φ) = adjacent / hypotenuse
In a right triangle, the two acute angles are complementary, which means that their sum is 90°. That is,θ + 90° = 90°
θ = 90° - 44°.Now we can use the given equation sin(θ) = cos(44°) and substitute θ: sin(90° - 44°) = cos(44°) => sin(46°) = cos(44°)
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the current in a certain river is known to be 2 kph. at full throttle, a boat makes a 4 km trip in this river (2 km upstream and 2 km downstream)in a total of 11 minutes. at full throttle, what is the speed of the boat in still water?
The speed of the boat in still water is 5 km/h.
Let's denote the speed of the boat in still water as "v" (in km/h). Since the boat travels 2 km upstream and 2 km downstream, we know that the total distance traveled is 4 km.
Let's first calculate the time taken to travel 2 km upstream. We know that the current is flowing at 2 km/h, so the effective speed of the boat relative to the river is (v - 2) km/h (since it is going against the current). Therefore, the time taken to travel 2 km upstream is
time taken = distance / speed = 2 / (v - 2) hours
Similarly, the time taken to travel 2 km downstream is
time taken = distance / speed = 2 / (v + 2) hours
The total time taken for the round trip (2 km upstream and 2 km downstream) is given as 11 minutes, which is equivalent to (11/60) hours. Therefore, we can write
2 / (v - 2) + 2 / (v + 2) = 11/60
Multiplying both sides by (v - 2)(v + 2) gives
2(v + 2) + 2(v - 2) = (v - 2)(v + 2)(11/60)
Simplifying the right-hand side gives
(v - 2)(v + 2)(11/60) = (11/3)v^2 - 44/3
Substituting this expression into the previous equation and simplifying gives
22v = (11/3)v^2 - 44/3
Multiplying both sides by 3 gives
66v = 11v^2 - 44
Rearranging and solving for v using the quadratic formula gives
v = (11 ± √(11^2 + 4×44))/22
Taking the positive solution (since v must be positive) gives
v = 5 km/h
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