Answer:
45° or 135°
Step-by-step explanation:
Cos 2x = 0
2x = cos^-1 0
2x = 90° or 270°
x= 45° or 135°
Answer:
Step-by-step explanation:
● cos 2x = 0
We khow that Pi/2 equals 0.
So
● 2x = Pi/2 or 2x= -Pi/2
Then:
● x = Pi/4 or x = -Pi/2
So the solutions are:
● x = Pi/4 + 2×k×Pi
● or x = -Pi/4 + 2×k×Pi
Where k is an integer
The picture below has a graphical solution
● Pi/4 is approximatively 0.785 and -Pi/4 is approximatively -0.785
● the output of both Pi/4 and -Pi/4 is 0
So our answer was righr
The development of AstroWorld ("The Amusement Park of the Future") on the outskirts of a city will increase the city's population at the rate given below in people/year t yr after the start of construction. 5,700 t 11,000 The population before construction is 67,000. Determine the projected population 16 yr after construction of the park has begun. people
Complete question :
The development of AstroWorld ("The Amusement Park of the Future") on the outskirts of a city will increase the city's population at the rate given below in people/year t yr after the start of construction. 5,700√t + 11,000 The population before construction is 67,000. Determine the projected population 16 yr after the construction of the park has begun. people
Answer:
486,200
Step-by-step explanation:
Given that the rate of change in population is represented by the function:
f(t) = 5,700√t + 11,000
To get the original function, we take the integral of the rate function because the rate of change is obtained by taking the derivate of the original equation
f(t) = 5,700t^1/2 + 11,000
Taking the integral of f with respect to t:
∫(5,700t^1/2 + 11,000)
[5700t^(1/2 + 1)] / (1/2 + 1) + 11000t + C
[(5700t^3/2)/ 3/2] + 11000t + C
Where C = constant
If population before construction = 67000
Then C = 67000
t = time = 16 years
Substitute values into the original change equation:
[(5700(16)^3/2)/ 3/2] + 11000t + 67000
[(5700 * 64) / 1.5] + 11000(16) + 67000
243200 + 176000 + 67000
= 486,200
State whether the data described below are discrete or continuous, and explain why.
The widths (in centimeters) of different paintings in an art museum
nothing
Choose the correct answer below.
A. The data are continuous because the data can only take on specific values.
B. The data are discrete because the data can only take on specific values.
C. The data are discrete because the data can take on any value in an interval.
D. The data are continuous because the data can take on any value in an interval.
In kickboxing, it is found that the force, f, needed to break a board, varies inversely with the length, l, of the board. If it takes 7 pounds of pressure to break a board that is 3 feet long, how long is a board that requires 5 pounds of pressure to break?
Answer:
4.2
Step-by-step explanation:
f varies inversly with L can be translated matimatically as:
● f = k/L
It takes 7 pounds of pressure to break a 3 feet long board.
Replace f by 7 and L by 3.
● 7 = k/3 => k=7×3=21
■■■■■■■■■■■■■■■■■■■■■■■■■■
Let's find tge length of a board that takes 5 pounds of pressure to be broken.
● 5 = k/L
● 5 = 21/L
● L = 21/5 = 4.2
So the board is 4.2 feet long
The graph represents this system of equations
y=4
y=3 - 1/2x . What is the solution to the system of equations
(-2,4)
(3,4)
(4,-2)
(4,3)
Hey there! I'm happy to help!
When graphing a system of equations, the solution is the point where the two lines meet. We see that they intersect at (-2,4).
Therefore, the solution to the system of equations is (-2,4).
Have a wonderful day! :D
Answer:
A
Step-by-step explanation:
edge 2020 Dec 9
If xy = 1 what is the arithmetic mean of x and y in terms of y? Please show work as detailed as possible
Answer:
(1+y^2) /2y
Step-by-step explanation:
arithmetic mean is the average of x and y
(x+y)/2
Using the equation
xy = 1
and solving for x
x = 1/y
Replacing x in the first equation
(1/y + y) /2
Multiply by y/y
(1/y + y) /2 * y/y
(1/y + y)*y /2y
(1+y^2) /2y
Which of the following is an example of closure? (1 point)
The equation 5 - 5 = 0 is an example of the natural numbers being closed under subtraction
The equation 1.5 +1.6 = 3.1 is an example of the rational numbers being closed under addition
The equation 4 - 6 = -2 is an example of the whole numbers being closed under subtraction
The equation 1+0= 1 is an example of the natural numbers being closed under addition
Answer:
The equation 1+0=1
Step-by-step explanation:
Other options are not eligible because
1 option -Natural numbers cannot be closed under subtraction
2 option-The equation is not having proper rational numbers, they are decimals
3 option-Whole numbers cannot be closed under subtraction
Thank you!
Find the solution of the inequality 5 > r - 3.
A) r<2
B) r = 2
C) r=8
(D) r < 8
Answer:
[tex]\huge\boxed{r<8}[/tex]
Step-by-step explanation:
[tex]5 > r - 3[/tex]
Adding 3 to both sides
[tex]5 + 3 > r[/tex]
[tex]8 > r\\OR \\r < 8[/tex]
Answer: D. r<8
Step-by-step explanation:
[tex]5>r-3[/tex]
add 3 to both sides
[tex]r-3+3<5+3[/tex]
[tex]5+3=8[/tex]
simplify
[tex]r<8[/tex]
10 - 2x, when x = 3
Answer:
4
Step-by-step explanation:
Plug in 3 as x in the expression:
10 - 2x
10 - 2(3)
10 - 6
= 4
Answer:
4
Step-by-step explanation:
10 - 2x
Let x =3
10 -2(3)
10 -6
4
What is the solution to the system of equations? -2x-3y+z=-6, z=6, 3x-y+z=13
Answer:
B is the correct answer.
Step-by-step explanation:
-2x+3y+z=-6
z=6
-2x+3y+6=-6
-2x+3y=-12
-2(3)+3(2)
-6+6=0 A is incorrect
-2(3)+3(-2)=-12
-6-6=-12
B is the correct answer.
I am not going to show C or D, because you have the right answer. Hope this helps you. Thank you.
one of these marbles is picked at random. what is the probability that a blue marble is picked?
A.1/3
B.2/5
C.1/2
D.1/4
Answer:
1/3
Step-by-step explanation:
there are twelve marbles total. there are 4 blue marbles.
4/12 = 1/3
Each corner of a rectangular prism is cut off. Two (of the eight) cuts are shown. How many edges does the new figure have? Assume that the planes cutting the prism do not intersect anywhere in or on the prism. EXPLAIN PLS
Answer:
36
Step-by-step explanation:
Each cut creates a triangular face where the corner used to be. That face adds three edges to the figure. The 8 cuts add a total of 8×3 = 24 edges to the 12 edges the prism already had.
The new figure has 12+24 = 36 edges.
A projectile is fired vertically upward from a height of 300
300
feet above the ground, with an initial velocity of 900
900
ft/sec. Recall that projectiles are modeled by the function h(t)=−16t2+v0t+y0
h
(
t
)
=
−
16
t
2
+
v
0
t
+
y
0
. Write a quadratic equation to model the projectile's height h(t)
h
(
t
)
in feet above the ground after t seconds.
Step-by-step explanation:
It is given that, a projectile is fired vertically upward from a height of 300 feet above the ground, with an initial velocity of 900 ft/s.
The general equation with which a projectile are modled by the function is given by :
[tex]h(t)=-16t^2+v_ot+y_o[/tex]
y₀ is the initial height above the ground
v₀ = initial velocity
So,
[tex]h(t)=-16t^2+900t+300[/tex]
This is the quadratic equation that models the projectile height in feet above the ground after t seconds.
An operator wants to determine the standard deviation for a machine relative to its ability to produce windshield wipers conforming within their specifications. To do this, she wants to create a p-chart. Over a month's time, she tests 100 units every day and records the number of manufacturing defects. The average proportion of non-conforming windshield wipers is found to be 0.042. What is the standard deviation of this sample
Answer:
the standard deviation of the sample is less than 0.1
Step-by-step explanation:
Given that :
The sample size n = 100 units
The average proportion of non-conforming windshield wipers is found to be 0.042 which is the defective rate P-bar
The standard deviation of the machine([tex]S_p[/tex]) can be calculated by using the formula:
[tex]S_p =\dfrac{ \sqrt{ \overline P \times (1 - \overline P)} }{n}[/tex]
[tex]S_p =\dfrac{ \sqrt{0.042 \times (1 -0.042)} }{100}[/tex]
[tex]S_p =\dfrac{ \sqrt{0.042 \times (0.958)} }{100}[/tex]
[tex]S_p =\dfrac{ \sqrt{0.040236} }{100}[/tex]
[tex]S_p =\dfrac{ 0.2005891323 }{100}[/tex]
[tex]S_p =0.002[/tex]
Thus , the standard deviation of the sample is less than 0.1
In the diagram, ∆ABC and ∆DBE are similar. What is the scale factor of the dilation that will map the preimage ΔABC onto the image ΔDBE? A. 1.33 B. 0.75 C. 0.66 D. 0.55
Answer:
B
Step-by-step explanation:
Calculate the ratio of corresponding sides, image to preimage, that is
scale factor = [tex]\frac{DE}{AC}[/tex] = [tex]\frac{12.09}{16.12}[/tex] = 0.75 → B
The scale factor of the dilation will be 1.33. Then the correct option is A.
What is dilation?Dilation is the process of increasing the size of an item without affecting its form. Depending on the scale factor, the object's size can be raised or lowered.
There is no effect of dilation on the angle.
In the diagram, ∆ABC and ∆DBE are similar.
Then the scale factor of the dilation that will map the preimage ΔABC onto the image ΔDBE will be
⇒ 16.12 / 12.09
⇒ 1.33
Then the correct option is A.
More about the dilation link is given below.
https://brainly.com/question/2856466
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Many stores run "secret sales": Shoppers receive cards that determine how large a discount they get, but the percentage is revealed by scratching off that black stuff only after the purchase has been totaled at the cash register. The store is required to reveal (in the fine print) the distribution of discounts available. Determine whether the following probability assignment is legitimate?
10% off 20% off 30% off 50% off
a. 0.2 0.2 0.2 0.2
b. 0.5 0.3 0.2 0.1
c. 0.8 0.1 0.05 0.05
d. 0.75 0.25 0.25 -0.25
e. 1 0 0 0
Answer:
b
Step-by-step explanation:
it makes the most senses the lower the discount the higher the chance
You are certain to get a red card when selecting 27 cards from a shuffled deck. Express the indicated degree of likelihood as a probability value between 0 and 1 inclusiv
Answer:
If something is guaranteed, it has a probability of 100%, or 1.
Step-by-step explanation:
A standard deck has 52 cards. Of these, half are red cards (diamonds and hearts) and half are black cards (clovers and spades)
Half of the deck is 26 cards (52 ÷ 2 = 26), so you have 26 red and 26 black cards.
What this means in our context is, if we draw 27 cards, even if we drew all 26 black cards, we would still have 1 red card.
So the probability is 100%, or 1, of drawing a red card when we pick 27 cards from a deck, no matter how it's shuffled
The probability of getting a red card is 1.
No matter how you shuffle the cards, the no of cards will remain the same.
Therefore, it will not affect the probability.
What is probability?
Probability is simply how likely something is to happen. Whenever we're unsure about the outcome of an event, we can talk about the probabilities of certain outcomes—how likely they are. The analysis of events governed by probability is called statistics.
Learn more about probability here: https://brainly.com/question/251701
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An ice cream store makes 144 quarts of ice cream in 8 hours. How many quarts could be made in 12 hours?
Hey there! I'm happy to help!
We know that the ice cream store makes 144 quarts in eight hours. What about in one hour? Let's divide this by eight to find out.
144/8=18
So, they make 18 quarts every hour. We want to figure out how many can be made in 12 hours. So, we just multiply 18 by 12!
18(12)=216
Therefore, 216 quarts of ice cream could be made in 12 hours.
Have a wonderful day! :D
The ice cream store will make 216 quarts of ice cream in 12 hours.
What is division?Division is breaking a number up into an equal number of parts.
Given that, An ice cream store makes 144 quarts of ice cream in 8 hours.
Since, they make 144 quarts of ice cream in 8 hours
Therefore, in 1 hour they will make = 144/8 = 18 quarts
So, in 12 hours = 18x12 = 216 quarts.
Hence, The ice cream store will make 216 quarts of ice cream in 12 hours.
For more references on divisions, click;
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It has been found that 26% of men 20 years and older suffer from hypertension (high blood pressure) and 31.5% of women are hypertensive. A random sample 150 of each gender was selected from recent hospital records, and the following results were obtained. Construct 95% confidence interval for the difference of the two proportion. Round your answer to nearest ten-thousandth. Interpret the result.
Complete Question
It has been found that 26% of men 20 years and older suffer from hypertension (high blood pressure) and 31.5% of women are hypertensive. A random sample 150 of each gender was selected from recent hospital records, and the following results were obtained.
Men. 43 patients had high blood pressure
Woman. 52 patients had high blood pressure.
Answer:
The 95% confidence interval is
[tex]- 0.1651 < p_m - p_f <0.0451[/tex]
This mean that there is a 95 % confidence that the difference between the true proportions of male and female that are hypertensive is within this interval and given that the interval contains zero then there is no statistically significant difference between the genders that are hypertensive
Step-by-step explanation:
From the question we are told that
The sample size for male is [tex]n_1 = 150[/tex]
The number of male that are hypertensive is [tex]m = 42[/tex]
The sample size of female is [tex]n_2 = 150[/tex]
The number of female that are hypertensive is [tex]q = 52[/tex]
The proportion of male that are hypertensive is mathematically represented as
[tex]\r p_m = \frac{43}{150}[/tex]
[tex]\r p_m = 0.287[/tex]
The proportion of female that are hypertensive is mathematically represented as
[tex]p_f = \frac{52}{150}[/tex]
[tex]p_f = 0.347[/tex]
From the question we are told that confidence level is 95%, hence the level of significance is mathematically represented as
[tex]\alpha = 100 -95[/tex]
[tex]\alpha =5\%[/tex]
[tex]\alpha =0.05[/tex]
Next we obtain the critical value of [tex]\frac{ \alpha }{2}[/tex] from the normal distribution table, the value is
[tex]Z_{\frac{ \alpha }{2} } = 1.96[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \sqrt{\frac{ \r p_m (1- \r p_m )}{n_1} + \frac{ \r p_f (1- \r p_f )}{n_2} }[/tex]
substituting value
[tex]E = 1.96 * \sqrt{\frac{ 0.287 (1- 0.287 )}{150} + \frac{ 0.347 (1- 0.347 )}{150} }[/tex]
[tex]E = 0.1051[/tex]
The 95% confidence interval is mathematically represented as
[tex](\r p_m - \r p_f ) - E < p_m - p_f < (\r p_m - \r p_f ) + E[/tex]
substituting values
[tex]( 0.287 - 0.347 ) - 0.1051 < p_m - p_f <( 0.287 - 0.347 ) + 0.1051[/tex]
[tex]- 0.1651 < p_m - p_f <0.0451[/tex]
This mean that there is a 95 % confidence that the difference between the true proportion is within this interval and given that the interval contains zero then there is no statistically significant difference between the genders that are hypertensive.
A racecar is traveling at a constant speed of 150 miles per hour. How many feet does it travel in 5 seconds? Remember that 1 mile is 5280 feet.
Answer:
distance covered in 5 seconds
= 1.4283 *10^10 feet
Step-by-step explanation:
A racecar is traveling at a constant speed of 150 miles per hour.
One mile = 5280 feet
150 miles= 5290*150
150 miles= 793500 feet
A racecar is traveling at a constant speed of 793500 feet per hour.
Converting 793500 feet per hour to feet per seconds .
793500 feet per hour
= 793500*60*60 feet per seconds
=2856600000 feet per second
In 5 seconds , distance covered
= 2856600000 *5
distance covered in 5 seconds
= 1.4283 *10^10 feet
Translate the statements into a confidence interval for p. Approximate the level of confidence. In a survey of 8451 U.S. adults, 31.4% said they were taking vitamin E as a supplement. The survey's margin of error is plus or minus 1%.
Answer:
The confidence interval is [tex]0.304 < p < 0.324[/tex]
Step-by-step explanation:
From the question we are told
The sample proportion [tex]\r p = 0.314[/tex]
The margin of error is [tex]E = 0.01[/tex]
The confidence interval for p is mathematically represented as
[tex]\r p - E < p < \r p + E[/tex]
=> [tex]0.314 - 0.01 < p < 0.314 + 0.01[/tex]
=> [tex]0.304 < p < 0.324[/tex]
An inequality is shown: −np − 4 ≤ 2(c − 3) Which of the following solves for n?
Answer:
[tex]\huge\boxed{n\leq\dfrac{2-2c}{p}\ \text{for}\ p<0}\\\boxed{n\geq\dfrac{2-2c}{p}\ \text{for}\ p>0}[/tex]
Step-by-step explanation:
[tex]-np-4\leq2(c-3)\qquad\text{use the distributive property}\\\\-np-4\leq2c-6\qquad\text{add 4 to both sides}\\\\-np\leq2c-2\qquad\text{change the signs}\\\\np\geq2-2c\qquad\text{divide both sides by}\ p\neq0\\\\\text{If}\ p<0,\ \text{then flip the sign of inequality}\\\boxed{n\leq\dfrac{2-2c}{p}}\\\text{If}\ p>0 ,\ \text{then}\\\boxed{n\geq\dfrac{2-2c}{p}}[/tex]
A website developer wished to analyze the clicks per day on their newly updated website. Let the mean number of clicks per day be μ. If the website developer wants to know if the number of clicks per day is different than 200 clicks a day, on average, what are the null and alternative hypotheses?
Answer:
Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = 200 clicks a day
Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu\neq[/tex] 200 clicks a day
Step-by-step explanation:
We are given that a website developer wished to analyze the clicks per day on their newly updated website.
The website developer wants to know if the number of clicks per day is different than 200 clicks a day, on average.
Let [tex]\mu[/tex] = mean number of clicks per day.
So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = 200 clicks a day
Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu\neq[/tex] 200 clicks a day
Here, the null hypothesis states that the mean number of clicks per day is 200 clicks a day.
On the other hand, the alternate hypothesis states that the mean number of clicks per day is different than 200 clicks a day.
Hence, this is the correct null and alternative hypotheses.
Answer: Null Hypothesis [tex]H_0:\mu=200[/tex]
Alternate Hypothesis[tex]H_a:\mu\neq200[/tex]
Step-by-step explanation:
Let [tex]\mu[/tex] be the mean number of clicks per day.
Given, a website developer wished to analyze the clicks per day on their newly updated website.
The website developer wants to know if the number of clicks per day is different than 200 clicks a day, on average.
i.e. he wants to check either [tex]\mu=200\text{ or }\mu\neq 200[/tex]
Since a null hypothesis is a hypothesis believes that there is no difference between the two variables whereas an alternative hypothesis believes that there is a statistically significant difference between two variables.
So, Null Hypothesis [tex]H_0:\mu=200[/tex]
Alternate Hypothesis[tex]H_a:\mu\neq200[/tex]
Hence, the required null and alternative hypotheses.
Null Hypothesis [tex]H_0:\mu=200[/tex]
Alternate Hypothesis[tex]H_a:\mu\neq200[/tex]
Suppose that you are standing 150 feet from a building and the angle of elevation to the top of the building is 42°. What is the building's height?
Answer:
135.06 feet
Step-by-step explanation:
Since the side of the building makes a right triangle with the ground and you know one side length and the degree angle between you and the top of the building we can use trigonometric function to find the height of the building. So since we know one side other than the hypotenuse we can use tangent to solve. Tangent is the opposite side over the adjacent side of the known angle.
opposite side = x
adjacent side = 150 feet
angle = 42°
tan(42°) = x/150 feet
150 feet * tan(42°) = x
x = 135.06 feet
Please solve this question by using the strategy Elimination Method or Solve By Substitution. This is the math equation: 1/2x+y=15 and -x-1/3y=-6
2nd Question: 5/6x+1/3y=0 and 1/2x-2/3y=3
First pair of equations :
[tex]\dfrac{1}{2}x+y=15\ ..(i)\\\\-x-\dfrac{1}{3}y=-6\ ..(ii)[/tex]
Multiply 2 to equation (i), we get
[tex]x+2y=30\ ..(iii)[/tex]
By Elimination Method, Add (i) and (ii) (term with x eliminate), we get
[tex]2y-\dfrac{1}{3}y=30-6\\\\\Rightarrow\ \dfrac{5}{3}y=24\\\\\Rightarrow\ y=\dfrac{24\times3}{5}=14.4[/tex]
put y= 14.4 in (iii), we get
[tex]x+2(14.4)=30\Rightarrow\ x=30-28.8=1.2[/tex]
hence, x=1.2 and y =14.4
Second pair of equations :
[tex]\dfrac{5}{6}x+\dfrac13y=0\ ..(i)\\\\ \dfrac12x-\dfrac{2}{3}y=3\ ..(ii)[/tex]
Multiply 2 to equation (i), we get
[tex]\dfrac{5}{3}x+\dfrac{2}{3}y=0\ ..(iii)[/tex]
Elimination Method, Add (i) and (ii) (term with y eliminate) , we get
[tex]\dfrac53x+\dfrac12x=3\Rightarrow\ \dfrac{10+3}{6}x=3\\\\\Rightarrow\ \dfrac{13}{6}x=3\\\\\Rightarrow\ x=\dfrac{18}{13}[/tex]
put [tex]x=\dfrac{18}{13}[/tex] in (i), we get
[tex]\dfrac{5}{6}(\dfrac{18}{13})+\dfrac{1}{3}y=0\\\\\Rightarrow\ \dfrac{15}{13}+\dfrac{1}{3}y=0\\\\\Rightarrow\ \dfrac{1}{3}y=-\dfrac{15}{13}\\\\\Rightarrow\ y=-\dfrac{45}{13}[/tex]
hence, [tex]x=\dfrac{18}{13}[/tex] and [tex]y=\dfrac{-45}{13}[/tex] .
The average daily volume of a computer stock in 2011 was ų=35.1 million shares, according to a reliable source. A stock analyst believes that the stock volume in 2014 is different from the 2011 level. Based on a random sample of 30 trading days in 2014, he finds the sample mean to be 32.7 million shares, with a standard deviation of s=14.6 million shares. Test the hypothesis by constructing a 95% confidence interval. Complete a and b A. State the hypothesis B. Construct a 95% confidence interval about the sample mean of stocks traded in 2014.
Answer:
a
The null hypothesis is [tex]H_o : \mu = 35 .1 \ million \ shares[/tex]
The alternative hypothesis [tex]H_a : \mu \ne 35.1\ million \ shares[/tex]
b
The 95% confidence interval is [tex]27.475 < \mu < 37.925[/tex]
Step-by-step explanation:
From the question the we are told that
The population mean is [tex]\mu = 35.1 \ million \ shares[/tex]
The sample size is n = 30
The sample mean is [tex]\= x = 32.7 \ million\ shares[/tex]
The standard deviation is [tex]\sigma = 14.6 \ million\ shares[/tex]
Given that the confidence level is [tex]95\%[/tex] then the level of significance is mathematically represented as
[tex]\alpha = 100-95[/tex]
[tex]\alpha = 5\%[/tex]
=> [tex]\alpha = 0.05[/tex]
Next we obtain the critical value of [tex]\frac{\alpha }{2}[/tex] from the normal distribution table
The value is [tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{ \sigma }{\sqrt{n} }[/tex]
substituting values
[tex]E = 1.96 * \frac{ 14.6 }{\sqrt{30} }[/tex]
[tex]E = 5.225[/tex]
The 95% confidence interval confidence interval is mathematically represented as
[tex]\= x -E < \mu < \= x +E[/tex]
substituting values
[tex]32.7 - 5.225 < \mu < 32.7 + 5.225[/tex]
[tex]27.475 < \mu < 37.925[/tex]
Question 1 (Multiple Choice Worth 4 points)
(08.01) Looking at the spread of your data best fits which step of the statistical process?
Answer:
The answer is "Analysis the information by chart and number processes".
Step-by-step explanation:
They already have articulated a query and also gathered information unless you are searching only at the distribution of your results. Those who are ready to analyze your results for all are there.
Oregon State University is interested in determining the average amount of paper, in sheets, that is recycled each month. In previous years, the average number of sheets recycled per bin was 59.3 sheets, but they believe this number may have increase with the greater awareness of recycling around campus. They count through 79 randomly selected bins from the many recycle paper bins that are emptied every month and find that the average number of sheets of paper in the bins is 62.4 sheets. They also find that the standard deviation of their sample is 9.86 sheets. What is the value of the test-statistic for this scenario
Answer:
The test statistic is [tex]t = 2.79[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 59.3[/tex]
The sample size is [tex]n = 79[/tex]
The sample mean is [tex]\= x = 62.4[/tex]
The standard deviation is [tex]\sigma = 9.86[/tex]
Generally the test statistics is mathematically represented as
[tex]t = \frac{\= x - \mu }{ \frac{ \sigma}{ \sqrt{n} } }[/tex]
substituting values
[tex]t = \frac{ 62.2 - 59.3 }{ \frac{ 9.86}{ \sqrt{ 79} } }[/tex]
[tex]t = 2.79[/tex]
The report "Teens and Distracted Driving: Texting, Talking and Other Uses of the Cell Phone Behind the Wheel" summarizes data from a survey of a representative sample of 800 teens between the ages of 12 and 17. The following statements were made on the basis of the resulting data.
- 75% of all American teens own a cellphone
- 66% of all American teens use a cellphone to send a receive text messages
- 26% of American teens age 16-17 have used a cellphone to text while driving
Required:
a. Is the inference made one that involves estimation or one that involved hypothesis testing?
b. What is the population of interest? American teenagers? American teenagers between ages 12-17? Americans? Teenagers?
Answer:
"Teens and Distracted Driving: Texting, Talking and Other Uses of the Cell Phone Behind the Wheel"
a. The inference made involves estimation. The question provided that the statements were made on the basis of the resulting data and not on the basis of some hypothesis testing.
This implies that some statistics were calculated from sample data to approximate the population parameter, as shown in the statements. The statements were not an attempt to establish the statistical significance of some claims.
b. The population of interest is American teenagers between 12-17.
Step-by-step explanation:
An inference from data is a statistical estimation by which some statistics are calculated based on the sample data of 800 teens between the ages of 12 and 17. The statistics serve as an approximation to the population parameter.
Inference based on hypothesis testing establishes if a claim has statistical significance by providing statistical evidence in favor of the claim or against it.
What is the area of the house (including the drawing room, TV room, balcony, hallway, kitchen, and bedroom)?
Answer:
A
Step-by-step explanation:
A cubical sandbox has a volume of 91.125 cubic inches. What is the side length of the
sandbox?
Hey there! I'm happy to help!
To find the volume of a cube, you simply cube the side length (multiply it by itself three times). This is because all of the sides of a cube are the same and if you multiply the length by the width by the height it is the same number multiplied by itself three times.
We already know that the volume is 91.125 cubic inches. To find the side length, we simply do the cube root on our calculator, which tells us what number we cube to get 91.125.
∛91.125=4.5
Therefore, the side length of the sandbox is 4.5 inches.
I hope that this helps! Have a wonderful day! :D