Answer:
a. SST = 1816
SSR = 1511.804
SSE = 465.804
b. Coefficient of determination, R² = 0.832491079
c. The correlation coefficient r = 0.8636
Step-by-step explanation:
y = 23.194 + 0.318·x
Where:
x = Price
y = Overall score
The observed data are given as follows;
Brand Price Score
Bose 180 76
Scullcandy 150 71
Koss 95 62
Phillips/O'Neill 70 57
Denon 70 30
JVC 35 34
[tex]SST = \sum \left (y - \bar{y} \right )^{2}[/tex]= 1816
[tex]SSR = \sum \left ({y}'-\bar{y{}'} \right )^{2}[/tex] = 1511.804
[tex]SSE = \sum \left (y - {y}' \right )^{2}[/tex] = 465.804
Coefficient of determination
[tex]Coefficient \, of \, determination = \dfrac{SSR}{SST}[/tex]= 0.832
Coefficient of correlation =
[tex]r = \dfrac{n\left (\sum xy \right )-\left (\sum x \right )\left (\sum y \right )}{\sqrt{\left [n\sum x^{2}-\left (\sum x \right )^{2} \right ]\left [n\sum y^{2}-\left (\sum y \right )^{2} \right ]}}[/tex]
Ʃxy = 37500
Ʃx =600
Ʃy = 330
Ʃx² = 74950
Ʃy² = 19966
[tex]r = \dfrac{6 \left (37500 \right )-\left (600 \right )\left (330 \right )}{\sqrt{\left [6\times 74950-\left (600 \right )^{2} \right ]\left [6 \times 19966-\left (330 \right )^{2} \right ]}} = 0.8636[/tex]
Here's a graph of a linear function. Write the
equation that describes that function.
Express it in slope-intercept form.
PLEASE HELP
Answer: [tex]y=\frac{3}{2} x - 3[/tex]
Step-by-step explanation:
Looking at the graph we could locate the y intercept at point (0,-3) and we can locate another point (4,3) which also passes through the line. So using these coordinates we already know the the y-intercept as -3 but we need to find the slope to write it in slope intercept form.
To find the slope, we will need to find the difference in the y values and divide it by the difference in the x values.
(0,-3)
(4,3)
-3 - 3 = -6
0-4 = -4
-6 /-4 = 3/2 so now we know that the slope is 3 over 2
so we could write the equation as y = 3/2x -3
Answer: Thank you (nermay7)
Step-by-step explanation: They are correct!!!!!!!
y=2x−4y=−12x+1 Question 1 options: a) (3, 2) b) (0, 2) c) (2, 0) d) (2, 3)
Classify the following triangle .check all that apply
Answer:
Isosceles right triangle
Answer:
It is a scalene triangle because 2 angles are equal and one angle is different .
Step-by-step explanation:
please mark as brainliest and follow me!!!!!...
Suppose a county’s population can be approximated with the function () = 34(1.00804) where is the number of years since 2000, and is measured in millions of citizens.
Answer:
Population = 34.27336
Step-by-step explanation:
Given:
Population function (t) = 34(1.00804)^t
Number of year = 2000
Find:
Number of citizen in year 2000
Computation:
We know that, base year is 2000
So, t = 1
Population function (t) = 34(1.00804)^t
Population function (1) = 34(1.00804)^1
Population = 34(1.00804)
Population = 34.27336
Therefore, Population is 34.273636 million
{(1,3),(2,5)(3,-4),(4-3),(5,1)} a function or not a function
Answer:
yes the above is a function.
A stack of 4 identical books is 6.28 high. What is the heigh of 30 of these books?
Answer:47.1
Step-by-step explanation:6.28/4=x/30
188.4=4x
47.1=x
Answer:
47.1
Step-by-step explanation:
height of 1 book=6.28÷4=1.57
height of 30 books=1.57×30=47.1
Erythropoietin (EPO) is a banned drug used by athletes to increase the oxygen-carrying capacity of their blood. New tests for EPO were first introduced prior to the 2000 Olympic Games held in Sydney, Australia. Chance (Spring 2004) reported that of a sample of 830 world-class athletes, 159 did not compete in the 1999 World Championships (a year prior to the new EPO test). Similarly, 133 of 82:5 potential athletes did not compete in the 2000 Olympic Games. Was the new test effective in deterring an athlete's participation in the 2000 Olympics? If so, then the proportion of nonparticipating athletes in 2000 will be greater than the proportion of nonparticipating athletes in 1999, Use a 98% confidence interval to compare the two proportions and make the proper conclusion.
Answer:
Step-by-step
The null and the alternative hypothesis can be define as follows,
Null Hypothesis; There is no significance difference between the proportions of non participating athletes in 1999 and 2000
[tex]H_0:(p_1-p_2)\neq 0[/tex]
Alternative Hypothesis: The proportion of non participating athletes in 2000 will be more than the proportion of non participating athletes in 1999
[tex]H_1:(p_1-p_2)<0[/tex]
The proportion of nonparticipating athletes in 1999 is given by
[tex]\hat p_1 = \frac{x_1}{n_1} \\\\=\frac{159}{830} =0.1916[/tex]
The proportion of nonparticipating athletes in 2000 is given by
[tex]\hat p_2 =\frac{x_2}{n_1} \\\\=\frac{133}{825} =0.1612[/tex]
The pooled proportion can be calculated using the following formula
[tex]\hat p = \frac{x_1+x_2}{n_1+n_2} \\\\=\frac{159+133}{830+825} =0.1764[/tex]
under the null hypothesis, the test statistics can be calculated as follows
[tex]Z=\frac{\hat p_1 - \hat p_2}{\sqrt{\hat p \hat q(\frac{1}{n_1}+\frac{1}{n_2} ) } }[/tex]
[tex]=\frac{0.1916-0.1612}{\sqrt{(0.1764)(0.8236)(\frac{1}{830} +\frac{1}{825} )} } \\\\=1.6257[/tex]
Determine the P-value using the following formula
P-value = Normdist(1.6257)
=0.947993
Here, it can be observed that the P-value is greater than the level of the significance,
Hence, the null hypothesis fails to be rejected
Therefore it can be concluded that there is insufficient evidence to support that the proportions of non participating athletes in 2000 will be more than the proportions of non participating athletes in 1999
3.14 The waiting time, in hours, between successive speeders spotted by a radar unit is a continuous random variable with cumulative distribution function F(x) = 0, x< 0, 1 − e−8x, x ≥ 0. Find the probability of waiting less than 12 minutes between successive speeders (a) using the cumulative distribution function of X; (b) using the probability density function of X.
Answer:
(a) The probability of waiting less than 12 minutes between successive speeders using the cumulative distribution function is 0.7981.
(b) The probability of waiting less than 12 minutes between successive speeders using the probability density function is 0.7981.
Step-by-step explanation:
The cumulative distribution function of the random variable X, the waiting time, in hours, between successive speeders spotted by a radar unit is:
[tex]F(x)=\left \{ {{0;\ x<0} \atop {1-e^{-9x};\ x\geq 0}} \right.[/tex]
(a)
Compute the probability of waiting less than 12 minutes between successive speeders using the cumulative distribution function as follows:
[tex]12\ \text{minutes}=\frac{12}{60}=0.20\ \text{hours}[/tex]
The probability is:
[tex]P(X<0.20)=|F (x)|_{x=0.20}[/tex]
[tex]=(1-e^{-8x})|_{x=0.20}\\\\=1-e^{-8\times 0.20}\\\\=0.7981[/tex]
Thus, the probability of waiting less than 12 minutes between successive speeders using the cumulative distribution function is 0.7981.
(b)
The probability density function of X is:
[tex]f_{X}(x)=\frac{d F (x)}{dx}=\left \{ {{0;\ x<0} \atop {8e^{-8x};\ x\geq 0}} \right.[/tex]
Compute the probability of waiting less than 12 minutes between successive speeders using the probability density function as follows:
[tex]P(X<0.20)=\int\limits^{0.20}_{0} {8e^{-8x}} \, dx[/tex]
[tex]=8\times [\frac{-e^{-8x}}{8}]^{0.20}_{0}\\\\=[-e^{-8x}]^{0.20}_{0}\\\\=(-e^{-8\times 0.20})-(-e^{-8\times 0})\\\\=-0.2019+1\\\\=0.7981[/tex]
Thus, the probability of waiting less than 12 minutes between successive speeders using the probability density function is 0.7981.
Which operation is the default operation in algebra?
Step-by-step explanation:
in mathematics, a basic algebra corporation is there any one of the traditional operation of arithmetic, which are addition, subtraction, multiply, division, rising to an integer power, and taking root (fractional power ).
In a certain city district the need for money to buy drugs is stated as the reason for 70% of all thefts. Find the probability that among the next 7 theft cases reported in this district, exactly 3 of them resulted from the need to buy drugs.
Answer:
9.72% probability that among the next 7 theft cases reported in this district, exactly 3 of them resulted from the need to buy drugs.
Step-by-step explanation:
For each theft, there are only two possible outcomes. Either the need to buy drugs is the reason of the theft, or it is not. Each theft is independent of each other. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
In a certain city district the need for money to buy drugs is stated as the reason for 70% of all thefts.
This means that [tex]p = 0.7[/tex]
Find the probability that among the next 7 theft cases reported in this district, exactly 3 of them resulted from the need to buy drugs.
This is P(X = 3) when n = 7. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 3) = C_{7,3}.(0.7)^{3}.(0.3)^{4} = 0.0972[/tex]
9.72% probability that among the next 7 theft cases reported in this district, exactly 3 of them resulted from the need to buy drugs.
How do I explain this answer
Answer:
199
Step-by-step explanation:
i dont know
Colgate claims that 90% of dentists recommend Colgate toothpaste. Suppose you randomly choose 10 dentists and ask whether they recommend Colgate toothpaste. What is the probability that exactly 8 dentists in your sample recommend Colgate toothpaste
Answer:
the probability that exactly 8 dentists in 10 samples recommend Colgate toothpaste is;
P(X) = 0.0043
P(X) = 0.43%
Step-by-step explanation:
The probability that a dentist recommend Colgate is;
P = 90% = 0.9
The probability that a dentist doesn't recommend Colgate is;
P' = 1 - P = 1 -0.9 = 0.1
Of 10 sample dentists, the probability that exactly 8 dentists recommend Colgate toothpaste is;
8 will recommend and two will not recommend it.
P(X) = P^8 × P'^2
P(X) = (0.9)^8 × (0.1)^2
P(X) = 0.0043
P(X) = 0.43%
The Probability of exactly 8 dentists in sample recommend Colgate toothpaste is 0.0043.
Since, Colgate claims that 90% of dentists recommend Colgate toothpaste.
Probability of dentist, who recommend Colgate toothpaste = 0.9
Probability of dentist, who does not recommend Colgate toothpaste,
= 1 - 0.9 = 0.1
When 10 dentist randomly choose , out of which 8 dentists recommend Colgate toothpaste. It means that 8 recommend Colgate toothpaste and 2 recommend other tooth paste.
Thus, The Probability of exactly 8 dentists in sample recommend Colgate ,
[tex]=(0.9)^{8}*(0.1)^{2} =0.0043[/tex]
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Help please!!! Everything is in the picture.
Answer:
3u-2v = [tex]\sqrt{505\\}[/tex]
5u-v = [tex]\sqrt{1,157}[/tex]
2u-3v = [tex]\sqrt{1,300}[/tex]
u+4v = [tex]\sqrt{4,505}[/tex]
Step-by-step explanation:
I just started by doing the results for each of the operations given.
3u-2v:
3u = (-9, 24) 2v = (-28, 12)
Do the operation of 3u-2v and you get a resultant vector of (19, 12).
You calculate this by doing the square root of 19^2 + 12^2, which is the square root of 505.
5u-v:
5u = (-15, 40) v = (-14, 6)
Do the operation of 5u-v and you get a resultant vector of (-1, 34).
You calculate this by doing the square root of (-1)^2 + 34^2, which is the square root of 1,157.
2u-3v:
2u = (-6, 16) 3v = (-42, 18)
Do the operation of 2u-3v and you get a resultant vector of (36, -2).
You calculate this by doing the square root of 36^2 + (-2)^2, which is the square root of 1,300.
3u+2v:
3u = (-9, 24) 2v = (-28, 12)
Do the operation of 3u+2v and you get a resultant vector of (-37, 36).
You calculate this by doing the square root of (-37)^2 + 36^2, which is the square root of 2,665. This is not a given tile, so we can just ignore this one.
u+4v:
u = (-3, 8) 4v = (-56, 24)
Do the operation of u+4v and you get a resultant vector of (-59, 32).
You calculate this by doing the square root of (-59)^2 + 32^2, which is the square root of 4,505.
Since this is a given tile, I didn't do 7u-2v, but you would use the same methodology.
maths
Ella mixes cordial and water in the ratio of 1:4 how much water should be mixed with 50ml or cordial
What is the average rate of change of f over the interval [-1, 4] Give an exact number.
Answer:
1.4
Step-by-step explanation:
The average rate of change is the "rise" divided by the "run".
rise/run = (f(4) -f(-1))/(4 -(-1)) = (0 -(-7))/(4+1)
rise/run = 7/5 = 1.4
The average rate of change on the interval [-1. 4] is 1.4.
We will see that the average rate of change in the given interval is 1.4
How to find the average rate of change?
For a given function f(x), the average rate of change on an interval [a, b] is given by:
[tex]r = \frac{f(b) - f(a)}{b - a}[/tex]
In this case the interval is [-1, 4], using the graph we can see that:
f(-1) = -7
f(4) = 0
replacing that in the formula we get:
[tex]r = \frac{0 - (-7)}{4 - (-1)} = \frac{7}{5} = 1.4[/tex]
If you want to learn more about rates of change, you can read:
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Rebecca Pearson is a widow and needs to take care of the expenses in her household. Her budget is below.
Find her net monthly cash flow. (Assume 1 month = 4 weeks)
Income Expenses
Salary: $2300/month
Rent: $1090/month
Groceries: $200/week
Utilities: $125/month
Car Insurance: $525 semiannually
Gasoline: $25/week
Miscellaneous: $200/month
Phone: $50/month
Hey there!
First, let's take all of the expenses and change the ones that aren't monthly into monthly.
Groceries: $800/month
Car insurance: $87.5/month
Gasoline: $100/month
Now, let's add together all of our expenses
1090+800+125+87.5+100+200+50=2452.5
Now, we subtract that from her salary.
2300-2452.5=-152.5
Therefore, Rebecca's net monthly cash flow is -$152.5. She should spend a bit less on groceries, not do so much miscellaneous, find a place that charges less rent, drive less, etc. so she isn't spending more than she earns.
I hope that this helps! Have a wonderful day!
is –68 + 90 positive or negative?
Answer:
22. positive
Step-by-step explanation:
–68 + 90
22
To ______ a function, you need to stretch or compress it
Answer: It’s to change the shape of a function
Step-by-step explanation:
To change the shape of a function, you need to stretch or compress it.
How to stretch or compress a function?In math terms, you can stretch or compress a function horizontally by multiplying x by some number before any other operations. To stretch the function, multiply by a fraction between 0 and 1. To compress the function, multiply by some number greater than 1.
Is there a function for every shape?By definition, a function has one possible output for any given input. So if you want your function defined as some y=f(x), then not every shape can be written as a function. Any shape that has two points directly above each other (relative to the x-axis) cannot be written as a function, even a piecewise one.
Learn more about the shape of a function, here: https://brainly.com/question/1884491
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In order to solve for the variable in the equation 2 (x + 3) + 5 x = 3 (2 x minus 1), Jaleesa begins by applying the distributive property, then combines like terms. Which equation is the result of these steps?
Answer:
7x+6 = 6x-3
Step-by-step explanation:
2 (x + 3) + 5 x = 3 (2 x - 1)
Distribute
2x+6+5x = 6x-3
Combine like terms
7x+6 = 6x-3
Answer:
7x + 6 = 6x - 3 Option A
Step-by-step explanation:
Now Jalesa wants to simplify this equation.
Firstly applying the distributive property
Distribute the 2 over the parenthesis and distribute the over the parenthesis
that is,
2*x + 2*3 + 5x = 3*2x - 3*1
2x + 6 + 5x = 6x - 3
After that combine like terms
2x + 5x + 6 = 6x - 3
7x + 6 = 6x - 3
Result is:
7x + 6 = 6x - 3
That's the final answer.
average of a data set was 40, and that standard deviation was 10, what else could you derive from that information.
Answer:
[tex] \bar x = 40, s =10[/tex]
And from these values we can estimate the sample variance like this:
[tex] s^2 = 10^2 =100[/tex]
And we can also estimate the coeffcient of variation given by:
[tex] \hat{CV} =\frac{s}{\bar x}[/tex]
And replacing we got:
[tex] \hat{CV} = \frac{10}{40}= 0.25[/tex]
And this coefficient is useful in order to see the variability in terms of the mean for this case since is lower than 1 we can conclude that this variation around the mean is low.
Step-by-step explanation:
For this case we have the following info given:
[tex] \bar x = 40, s =10[/tex]
And from these values we can estimate the sample variance like this:
[tex] s^2 = 10^2 =100[/tex]
And we can also estimate the coeffcient of variation given by:
[tex] \hat{CV} =\frac{s}{\bar x}[/tex]
And replacing we got:
[tex] \hat{CV} = \frac{10}{40}= 0.25[/tex]
And this coefficient is useful in order to see the variability in terms of the mean for this case since is lower than 1 we can conclude that this variation around the mean is low.
SOLVE THE EQUATION SHOW YOUR WORK 3x = 45
Answer:
x = 15
Step-by-step explanation:
3x = 45
x = 45/3
x = 15
Answer:
15
Step-by-step explanation:
3x = 45
Dividing 3 from both sides gives you
[tex]x = 45/3\\\\[/tex]
Now that isolated x.
[tex]45/3 = 15[/tex]
So x = 15
:D
IQ levels: A study investigated whether there are differences between the mean IQ level of people who were reared by their biological parents and those who were reared by someone else. What is the null hypothesis in this case
Answer:
The null hypothesis: there is no difference between the mean IQ level of people who were reared by their biological parents and those who were reared by someone else.
Step-by-step explanation:The null hypothesis can be a general statement mostly in statistics that proposes no difference or no relationship between 2 phenomena etc
Researchers always carry out a study to test against the null hypothesis ie the opposite of the null hypothesis showing that there is a difference. In this study, the researchers aim is to establish that there is a difference between the mean IQ level of people who were reared by their biological parents and those who were reared by someone else. This goes against the null which states that
there is no difference between the mean IQ level of people who were reared by their biological parents and those who were reared by someone else.
If the captain has a 3/4 probability of hitting the ship and the pirate has a 1/4 probably what is the probability the pirate hits and the captain misses
Answer:
9/16
Step-by-step explanation:
captain has a 3/4 probability of hitting the ship
pirate has a 1/4 probability of hitting the ship
This means he has a 3/4 probability of missing the ship
P (captain hitting and pirate missing) = 3/4*3/4 = 9/16
Suppose that a researcher is planning a new study on hemoglobin levels amongst women under 25 years old. Previous research suggest that the standard deviation of hemoglobin is 0.7 g/dl. In the new study the research wants to have the standard error for the sample mean to be no more than 0.05 g/dl. Find the required sample size for the new study.
Answer:
A sample size of at least 531 is required.
Step-by-step explanation:
We are lacking the confidence level to solve this question, so i am going to use a 90% confidence level.
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1-0.9}{2} = 0.05[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.05 = 0.95[/tex], so [tex]z = 1.645[/tex]
Now, find the margin of error M as such
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Find the required sample size for the new study.
A sample size of at least n is required.
n is found when [tex]M = 0.05[/tex]
We have that [tex]\sigma = 0.7[/tex]
So
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.05 = 1.645*\frac{0.7}{\sqrt{n}}[/tex]
[tex]0.05\sqrt{n} = 1.645*0.7[/tex]
[tex]\sqrt{n} = \frac{1.645*0.7}{0.05}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.645*0.7}{0.05})^{2}[/tex]
[tex]n = 530.4[/tex]
Rounding up
A sample size of at least 531 is required.
A sinusoid is any function whose values repeat in a periodic manner.
A. True
B. False
SUBMIT
Answer: short answer
Just checked it’s False
Hope this helps :))
Step-by-step explanation:
Answer:
B. False
Step-by-step explanation:
A P E X
You are testing the claim that the mean GPA of night students is different from the mean GPA of day students. You sample 30 night students, and the sample mean GPA is 2.35 with a standard deviation of 0.46. You sample 25 day students, and the sample mean GPA is 2.58 with a standard deviation of 0.47. Test the claim using a 5% level of significance. Assume the sample standard deviations are unequal and that GPAs are normally distributed. Give answer to exactly 4 decimal places.Hypotheses:sub(H,0):sub(μ,1) = sub(μ,2)sub(H,1):sub(μ,1) ≠ sub(μ,2)**I'm not sure how to calculate this in excel***Enter the test statistic - round to 4 decimal places.A=Enter the p-value - round to 4 decimal places.A=
Answer:
Step-by-step explanation:
This is a test of 2 independent groups. The population standard deviations are not known. Let μ1 be the mean GPA of night students and μ2 be the mean GPA of day students.
The random variable is μ1 - μ2 = difference in the mean GPA of night students and the mean GPA of day students.
We would set up the hypothesis.
The null hypothesis is
H0 : μ1 = μ2 H0 : μ1 - μ2 = 0
The alternative hypothesis is
H1 : μ1 ≠ μ2 H1 : μ1 - μ2 ≠ 0
This is a two tailed test.
Since sample standard deviation is known, we would determine the test statistic by using the t test. The formula is
(x1 - x2)/√(s1²/n1 + s2²/n2)
From the information given,
μ1 = 2.35
μ2 = 2.58
s1 = 0.46
s2 = 0.47
n1 = 30
n2 = 25
t = (2.35 - 2.58)/√(0.46²/30 + 0.47²/25)
t = - 1.8246
The formula for determining the degree of freedom is
df = [s1²/n1 + s2²/n2]²/(1/n1 - 1)(s1²/n1)² + (1/n2 - 1)(s2²/n2)²
df = [0.46²/30 + 0.47²/25]²/[(1/30 - 1)(0.46²/30)² + (1/25 - 1)(0.47²/25)²] = 0.00025247091/0.00000496862
df = 51
We would determine the probability value from the t test calculator. It becomes
p value = 0.0746
Since alpha, 0.05 < than the p value, 0.0746, then we would fail to reject the null hypothesis.
Kimberly goes on a road trip; her car gets 25 miles per gallon (mpg) and gas costs $3.24 per gallon. Let n represent the number of miles Kimberly has traveled since she started driving.
a. Suppose Kimberly has traveled 252 miles (n 252) since she started driving. i. How many gallons of gasoline has she used since she started driving? gallons Preview i. What is the cost of the gasoline that she has used since she started driving?
b. Write an expression in terms of n that represents the number of gallons of gasoline she has used since she started driving.
c. Write an expression in terms of n that represents the cost of the gasoline that she has used since she started driving.
Answer:
a) 10.08 gallons and $32.66 of gas
b) gallons used = n/25
c)cost of the gasoline = [tex]\frac{n}{25}(3.24)[/tex]
Step-by-step explanation:
a) We know that Kimberly has traveled 252 miles and we also know that her car gets 25 miles per gallon. We can apply proportions and rule of three:
25 miles ------ 1 gallon
252 miles ----- x gallons
Solving for x:
x gallons = 252 miles(1 gallon)/25 miles= 10.08 gallons.
Thus, she has used 10.08 gallons since she started driving.
Now we need to know the cost of the gasoline that she has used.
We know that each gallon of gas costs $3.24 and she has used 10.08 gallons. Again, we can apply proportions and rule of three:
1 gallon ------ 3.24 dollars
10.08 gallons---- x dollars.
Solving for x we get:
[tex]x=(10.08)(3.24)[/tex]= 32.659=32.66 dollars.
Thus, she has used $32.66 of gas since she started driving.
b) Write an expression in terms of n that represents the number of gallons of gasoline she has used since she started driving.
If we know that n is the number of miles that she drives, from what we wrote above, an expression to know the number of gallons she has used would be:
Gallons used = n/25 (since her car gets 25 miles per gallon) where n is the number of miles.
c) Write an expression in terms of n that represents the cost of the gasoline that she has used since she started driving.
Again, to know the cost of the gasoline we first need to know how many gallons she has used. From b) we know that the expression to know how many gallons she has used is n/25. Since each gallon costs $3.24 we will multiply this number by n/25 and we will get the cost (like we did in a))
Therefore, the cost of the gasoline = [tex]\frac{n}{25}(3.24)[/tex] where n is the number of miles.
Given cot ø = 4/3. Find the other two reciprocal trigonometic ratios. 1) scs 2) sec
Answer:
csc ø = 5/3 ; sec ø = 5/4
Step-by-step explanation:
cot ø = adj/opp
adj = 4
opp = 3
after that, we must find the hypotenuse by using phytagoras theorem
hpy² = adj² + opp²
hpy² = 4² + 3²
hpy² = 25
hpy = 5
now let's find the other
csc ø (not scs) = hyp/opp = 5/3
sec ø = hyp/adj = 5/4
Sidney made $35 less than four times Casey’s weekly salary. If x represents Casey’s weekly salary, write an expression for Sidney’s weekly salary.
Answer: [tex]y=4x-35[/tex]
y = Sidney’s weekly salary
x = Casey’s weekly salary
Answer: y=4x-35
x is Casey's salary
Y is Sidney's salary
Step-by-step explanation:
Sidney makes a quarter of Casey,
y=4x,
Then it also states that he makes 35 less than the first equation.
Therefore,
Y=4x-35
Which data collection method would provide an unbiased sample?
Answer:
The best data collection method or sampling method to provide an unbiased sample is the random sampling method.
Step-by-step explanation:
There are 5 popular known sampling methods or data collection methods.
1) Random Sampling
In random sampling, each member of the population would have an equal chance of being surveyed. One of the best ways to use random sampling is to give all the members of the population numbers and then use computer to generate random numbers and pick the members of the population with those random numbers.
2) Systematic sampling is easier than random sampling. In systematic sampling, a particular number, n, is counted repeatedly and each of the nth member is picked to be sampled.
3) Convenience Sampling
This is the worst sampling technique. It is also the easiest. In Convenience sampling, the surveyor just picks the first set of members of the population that they find and surveys.
4) Stratified Sampling
Stratified sampling divides the population into groups called strata. A sample is taken from each of these strata using either random, systematic, or convenience sampling.
5) Cluster sampling
Cluster Sampling divides the population into groups which are called clusters or blocks. The clusters are selected randomly, and some members or every element/member in the selected clusters is surveyed.
Hope this Helps!!!