Answer:
[tex]\boxed{6.875 \text{\: grams}}[/tex]
Step-by-step explanation:
Half-lives are how long it takes for half of a substance to decay. If you start with a certain amount and it decays for a certain amount of half-lives, you are dividing by [tex]2^{x}[/tex], where x is equal to the amount of half-lives.
In order to solve this question, simply divide the starting value by 2 raised to the value of half-lives.
[tex]\large\boxed{\frac{220}{2^{5}}=6.875\text{\: grams}}[/tex]
Identify the decimals labeled with the letters A, B, and C on the scale below. Letter A represents the decimal Letter B represents the decimal Letter C represents the decimal
[tex]10[/tex] divisions between $389$ and $390$ so each division is $\frac{390-389}{10}=0.1$
A is 8 division from $389$, so, A is $389+8\times 0.1=389.8$
similarly, C is one division behind $389$ so it is $389-1\times 0.1=388.9$
and B is $390.3$
Josephine has a rectangular garden with an area of 2x2 + x – 6 square feet. A rectangle labeled 2 x squared + x minus 6 Which expressions can represent the length and width of the garden? length = x2 – 3 feet; width = 2 feet length = 2x + 3 feet; width = x – 2 feet length = 2x + 2 feet; width = x – 3 feet length = 2x – 3 feet; width = x + 2 feet
Answer:
2x^2 + x - 6 = rectangular garden: length = 2x – 3 feet; width = x + 2 feet
Step-by-step explanation:
(2x - 3)(x + 2) = 2x^2 + x - 6 =
2x^2 + 4x - 3x - 6 = 2x^2 + x - 6 =
2x^2 + x - 6
You get the original equation from the two sides multiplied. :)
Hope this helps, have a good day.
The length and width of the rectangle will be (2x – 3) and (x + 2). Then the correct option is D.
What is the area of the rectangle?Let W be the rectangle's width and L its length.
The area of the rectangle is the multiplication of the two different sides of the rectangle. Then the rectangle's area will be
Area of the rectangle = L × W square units
The area is 2x² + x – 6 square feet. Then the factor of the equation is given as,
A = 2x² + x – 6
A = 2x² + 4x – 3x – 6
A = 2x(x + 2) – 3(x + 2)
L × W = (2x – 3)(x + 2)
The length and width of the rectangle will be (2x – 3) and (x + 2). Then the correct option is D.
More about the area of the rectangle link is given below.
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A plan for a dog park has a grassy section and a sitting section as shown in the figure. Which equation can be used to find the area of the grassy section?
Answer:
length times width
Step-by-step explanation:
The following shape is based only on squares, semicircles, and quarter circles. Find the area of the shaded part.
Answer:
this? hope it helps ........
Answer:
The answer is area=32pi-64 and the perimeter is 8pi
Step-by-step explanation:
The graph of F(x), shown below in pink, has the same shape as the graph of
G(x) = x3, shown in gray. Which of the following is the equation for F(x)?
Greetings from Brasil...
In this problem we have 2 translations: 4 units horizontal to the left and 3 units vertical to the bottom.
The translations are established as follows:
→ Horizontal
F(X + k) ⇒ k units to the left
F(X - k) ⇒ k units to the right
→ Vertical
F(X) + k ⇒ k units up
F(X) - k ⇒ k units down
In our problem, the function shifted 4 units horizontal to the left and 3 units vertical to the bottom.
F(X) = X³
4 units horizontal to the left: F(X + 4)
3 units vertical to the bottom: F(X + 4) - 3
So,
F(X) = X³
F(X + 4) - 3 = (X + 4)³ - 3The transformed function is f ( x ) = ( x + 4 )³ - 3 and the graph is plotted
What happens when a function is transformed?Every modification may be a part of a function's transformation.
Typically, they can be stretched (by multiplying outputs or inputs) or moved horizontally (by converting inputs) or vertically (by altering output).
If the horizontal axis is the input axis and the vertical is for outputs, if the initial function is y = f(x), then:
Vertical shift, often known as phase shift:
Y=f(x+c) with a left shift of c units (same output, but c units earlier)
Y=f(x-c) with a right shift of c units (same output, but c units late)
Vertical movement:
Y = f(x) + d units higher, up
Y = f(x) - d units lower, d
Stretching:
Stretching vertically by a factor of k: y = k f (x)
Stretching horizontally by a factor of k: y = f(x/k)
Given data ,
Let the function be represented as g ( x )
Now , the value of g ( x ) = x³
And , the transformed function has coordinates as A ( -4 , -3 )
So , when function is shifted 4 units to the left , we get
g' ( x ) = ( x + 4 )³
And , when the function is shifted vertically by 3 units down , we get
f ( x ) = ( x + 4 )³ - 3
Hence , the transformed function is f ( x ) = ( x + 4 )³ - 3
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Rob sent an email survey to 2,000 cell phone owners asking about their satisfaction with their current plan. Only 256 people returned the survey and they were predominately 18-24 years old.
Which of the following statements is true?
Rob is ignoring the assumption that all survey participants will want to act independently.
The survey likely has bias because the people who could not answer differ from those who did answer.
Rob included too many people on the survey list, affecting the data collected.
The survey suffers from census issues because only 256 people responded.
Answer:
option B
everyone has different opinions about different things, since we only recorded the survey of a fourth of the total people, the survey will definitely have bias since the people who dont have to answer survey will not be able to record their opinions
You run a souvenir store that sells key rings. You can get 50 key rings from your first supplier for $.50 cents each. You can get the same 50 key rings from your second supplier for $30 total, or you can get them from your third supplier for $27.50. How much will you pay if you get the best deal?
Answer:
$25
Step-by-step explanation:
.5 * 50 = 25
25<27.5<30
The cheapest supplier is the first one.
Kenji earned the test scores below in English class.
79, 91, 93, 85, 86, and 88
What are the mean and median of his test scores?
Answer:
mean=87
median=87
Step-by-step explanation:
mean=sum of test score/number of subject
mean=79+91+93+85+86+88/6
mean=522/6
mean=87
Literal meaning of median is medium.
To find the number which lies in the medium, we must rearrange the number in ascending.
79, 91, 93, 85, 86, 88
79, 85, 86, 88, 91, 93
86+88/2=87
Hope this helps ;) ❤❤❤
Let me know if there is an error in my answer.
Suppose that a sample mean is .29 with a lower bound of a confidence interval of .24. What is the upper bound of the confidence interval?
Answer:
The upper bound of the confidence interval is 0.34
Step-by-step explanation:
Here in this question, we want to calculate the upper bound of the confidence interval.
We start by calculating the margin of error.
Mathematically, the margin of error = 0.29 -0.24 = 0.05
So to get the upper bound of the confidence interval, we simply add this margin of error to the mean
That would be 0.05 + 0.29 = 0.34
a
A solid metal cone of base radius a cm and height 2a cm is melted and solid
spheres of radius are made without wastage. How many such spheres can be
made?
volume of a cone
.
.
.
volume of sphere
.
.
number of spheres that can be made......
.
.
hence a hemisphere can be formed
RATIO AND PROPORTION PROGRAM ENHANCEMENT UNIT PAUL IS PAID 473.88 FOR 38 1/4 HOURS OF WORK WHAT AMOUNT SHOULD HE BE PAID FO 40 HOURS
Answer:
495.56 should be p[aid for 40 hours.
Step-by-step explanation:
concept used
In ratio
a:b = c:d
__________________________________________
Given
IS PAID 473.88 FOR 38 1/4 HOURS OF WORK
38 1/4 hour = 38.25 hours
if we get ratio for payment per hour
we have
473.88 / 38.25 or 473.88 : 38.25
___________________________________
now we have to find payment for 40 hours
let that payment be x
thus, ratio for payment per hour in this case will be
x/40 or x:40
since
x:40 and 473.88 : 38.25 is representative of same program enhancement unit both ratio will be equal
thus
x:40 = 473.88 : 38.25
x/40 = 473.88 / 38.25
=> x = 40*(473.88 / 38.25 ) = 495.56
Thus, 495.56 should be p[aid for 40 hours.
What is the most precise name for quadrilateral ABCD with vertices A(–5,2), B(–3, 5),C(4, 5),and D(2, 2)?
Answer: ABCD is a parallelogram.
Step-by-step explanation:
First we plot these point on a graph as given in attachment.
From the attachment we can observe that AD || BC || x-axis .
also, AB ||CD, that will make ABCD a parallelogram , but to confirm we check the property of parallelogram "diagonals bisect each other" , i.e . "Mid point of both diagonals are equal".
Mid point of AC= [tex](\dfrac{-5+4}{2},\dfrac{2+5}{2})=(\dfrac{-1}{2},\dfrac{7}{2})[/tex]
Mid point of BD= [tex](\dfrac{-3+2}{2},\dfrac{5+2}{2})=(\dfrac{-1}{2},\dfrac{7}{2})[/tex]
Thus, Mid point of AC=Mid point of BD
i.e. diagonals bisect each other.
That means ABCD is a parallelogram.
Answer: ABCD is a parallelogram.
Step-by-step explanation:
First, we plot these points on a graph as given in the attachment. From the attachment, we can observe that AD || BC || x-axis. Also, AB ||CD, which will make ABCD a parallelogram, but to confirm, we check the parallelogram property "diagonals bisect each other," i.e., "Midpoint of both diagonals is equal."
The midpoint of AC=. The midpoint of BD=. Thus, the Midpoint of AC=Mid point of BD diagonals bisects each other. That means ABCD is a parallelogram.
domain and range A) D: (–7, –2], (–1, 3] R: (–10, 9.2] B) D: [–7, –2], [–1, 3] R: [–10, 9.2] C) D: (–7, 3] R: (–10, 9.2] D) D: (–7, –2), (–1, 3) R: (–10, 9.2)
Answer:
[tex]\Large \boxed{\mathrm{C) \ D: (-7, 3] \ R: (-10, 9.2]}}[/tex]
Step-by-step explanation:
The domain is the set of all possible x values.
The range is the set of all possible y values.
For the domain, we observe the graph, the graph will contain all the x values shown on the x-axis.
[tex]\mathrm{D= (-7,3] }[/tex]
For the range, we observe the graph, the graph will contain all the y values shown on the y-axis.
[tex]\mathrm{R= (-10,9.2] }[/tex]
50 POINTS!!! i WILL GIVE BRAINLISET IF YOU ANSWER FAST Find the domain for the rational function f of x equals quantity x minus 3 over quantity 4 times x minus 1. (−∞, 3)(3, ∞) (−∞, −3)( −3, ∞) negative infinity to one fourth and one fourth to infinity negative infinity to negative one fourth and negative one fourth to infinity
Answer:
[tex](-\infty,1/4)\cup(1/4,\infty)[/tex]
The answer is C.
Step-by-step explanation:
We are given the rational function:
[tex]\displaystyle f(x) = \frac{x-3}{4x-1}[/tex]
In rational functions, the domain is always all real numbers except for the values when the denominator equals zero. In other words, we need to find the zeros of the denominator:
[tex]\displaystyle \begin{aligned}4x -1 & = 0 \\ \\ 4x & = 1 \\ \\ x & = \frac{1}{4} \end{aligned}[/tex]
Therefore, the domain is all real number except for x = 1/4.
In interval notation, this is:
[tex](-\infty,1/4)\cup(1/4,\infty)[/tex]
The left interval represents all the values to the left of 1/4.The right interval represents all the values to the right of 1/4. The union symbol is needed to combine the two. Note that we use parentheses instead of brackets because we do not include the 1/4 nor the infinities.
In conclusion, our answer is C.
Answer:
The third one
Step-by-step explanation:
How do you compress this?
[tex]\displaystyle\\(a+b)^n\\T_{r+1}=\binom{n}{r}a^{n-r}b^r\\\\\\(x+2)^7\\a=2x\\b=3\\r+1=4\Rightarrow r=3\\n=5\\T_4=\binom{5}{3}\cdot (2x)^{5-3}\cdot3^3\\T_4=\dfrac{5!}{3!2!}\cdot 4x^2\cdot27\\T_4=\dfrac{4\cdot5}{2}\cdot 4x^2\cdot27\\\\T_4=1080x^2[/tex]
Independent random samples taken on two university campuses revealed the following information concerning the average amount of money spent on textbooks during the fall semester.
University A University B
Sample Size 50 40
Average Purchase $260 $250
Standard Deviation (s) $20 $23
We want to determine if, on the average, students at University A spent more on textbooks then the students at University B.
a. Compute the test statistic.
b. Compute the p-value.
c. What is your conclusion? Let α = 0.05.
Answer:
The calculated Z= 10/4.61 = 2.169
The P value is 0.975 .
Since the calculated value of z= 2.169 falls in the rejection region we therefore reject the null hypothesis at 5 % significance level . On the basis of this we conclude that the students at University A do not spend more on textbooks then the students at University B.
Step-by-step explanation:
We set up our hypotheses as
H0 : x 1= x2 and Ha: x1 ≠ x2
We specify significance level ∝= 0.05
The test statistic if H0: x1= x2 is true is
Z = [tex]\frac{x_1-x_2}\sqrt\frac{s_1^2}{n_1}+ \frac{s_2^2}{n_2}[/tex]
Z = 260-250/ √400/50 + 529/40
Z= 10 / √8+ 13.225
Z= 10/4.61 = 2.169
The critical value for two tailed test at alpha=0.05 is ± 1.96
The P value is 0.975 .
It is calculated by dividing alpha by 2 for a two sided test and subtracting from 1. When we subtract 0.025 ( 0.05/2)from 1 we get 0.975
Since the calculated value of z= 2.169 falls in the rejection region we therefore reject the null hypothesis at 5 % significance level . On the basis of this we conclude that the students at University A do not spend more on textbooks then the students at University B.
A mass of 5 kg stretches a spring 10 cm. The mass is acted on by an external force of 10sin( t ) N(newtons) and moves in a medium that imparts a viscous force of 2 N
when the speed of the mass is 4 cm/s. If the mass is set in motion from its equilibrium position with an initial velocity of 3 cm/s, formulate the initial value problem describing the motion of the mass.
A)Find the solution of the initial value problem in the above problem.
B)Plot the graph of the steady state solution
C)If the given external force is replaced by a force of 2 cos(ωt) of frequency ω , find the value of ω for which the amplitude of the forced response is maximum.
Answer:
A) C1 = 0.00187 m = 0.187 cm, C2 = 0.0062 m = 0.62 cm
B) A sample of how the graph looks like is attached below ( periodic sine wave )
C) w = [tex]\sqrt[4]{3}[/tex] is when the amplitude of the forced response is maximum
Step-by-step explanation:
Given data :
mass = 5kg
length of spring = 10 cm = 0.1 m
f(t) = 10sin(t) N
viscous force = 2 N
speed of mass = 4 cm/s = 0.04 m/s
initial velocity = 3 cm/s = 0.03 m/s
Formulating initial value problem
y = viscous force / speed = 2 N / 0.04 m/s = 50 N sec/m
spring constant = mg/ Length of spring = (5 * 9.8) / 0.1 = 490 N/m
f(t) = 10sin(t/2) N
using the initial conditions of u(0) = 0 m and u"(0) = 0.03 m/s to express the equation of motion
the equation of motion = 5u" + 50u' + 490u = 10sin(t/2)
A) finding the solution of the initial value
attached below is the solution and
B) attached is a periodic sine wave replica of how the grapgh of the steady state solution looks like
C attached below
The value of y varies directly with x . Find the value of k when y 33.6 and x = 4.2
Answer:
k=8
Step-by-step explanation:
Since y and x are in direct proportions, the equation is
y= kx, where k is a constant.
when y= 33.6, x=4.2,
33.6= k(4.2)
k= 33.6 ÷4.2
k=8
Answer:
k=8
Step-by-step explanation:
Consider the function below. (If an answer does not exist, enter DNE.) f(x) = x3 − 27x + 3 (a) Find the interval of increase. (Enter your answer using interval notation.)
Answer:
(-∞,-3) and (3,∞)
Step-by-step explanation:
f(x) = x³ − 27x + 3
1. Find the critical points
(a) Calculate the first derivative of the function.
f'(x) = 3x² -27
(b) Factor the first derivative
f'(x)= 3(x² - 9) = 3(x + 3) (x - 3)
(c) Find the zeros
3(x + 3) (x - 3) = 0
x + 3 = 0 x - 3 = 0
x = -3 x = 3
The critical points are at x = -3 and x = 3.
2. Find the local extrema
(a) x = -3
f(x) = x³ − 27x + 3 = (-3)³ - 27(-3) + 3 = -27 +81 + 3 = 57
(b) x = 3
f(x) = x³ − 27x + 3 = 3³ - 27(3) + 3 = 27 - 81 + 3 = -51
The local extrema are at (-3,57) and (3,-51).
3, Identify the local extrema as maxima or minima
Test the first derivative (the slope) over the intervals (-∞, -3), (-3,3), (3,∞)
f'(-4) = 3x² -27 = 3(4)² - 27 = 21
f'(0) = 3(0)² -27 = -27
f'(4) = 3(4)² - 27 = 51
The function is increasing on the intervals (-∞,-3) and (3,∞).
The graph below shows the critical points of your function.
A bag of 100 hard candies included 30 butterscotch, 40 peppermint, 15 strawberry, 10 orange, and 5 banana. The probability that the first candy pulled out of the bag will be butterscotch or strawberry is .45
a) true
b) false
Answer:
true
Step-by-step explanation:
there is 100 candies. That means we can easily turn the amount of each type of candy into a percent. there was 30 butterscotch which means that is 30 percent. There was 15 strawberry which means that is 15 percent. add that and you get 45. This is a shortcut and i advise you use the way your teacher taught you.
[tex]|\Omega|=100\\|A|=30+15=45\\\\P(A)=\dfrac{45}{100}=0.45[/tex]
So TRUE
Which of the following represents "next integer after the integer n"? n + 1 n 2n
Answer:
n + 1
Step-by-step explanation:
Starting with the integer 'n,' we represent the "next integer" by n + 1.
The mean salary of federal government employees on the General Schedule is $59,593. The average salary of 30 state employees who do similar work is $58,800 with \sigmaσσ= $1500. At the 0.01 level of significance, can it be concluded that state employees earn on average less than federal employees? What is the critical value? Round your answer to the nearest hundredths.
Answer:
Yes it can be concluded that state employees earn on average less than federal employees
The critical value is [tex]Z_{\alpha } = - 2.33[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = \$ 59593[/tex]
The sample size is n = 30
The sample mean is [tex]\= x = \$ 58800[/tex]
The standard deviation is [tex]\sigma = \$ 1500[/tex]
The significance level is [tex]\alpha = 0.01[/tex]
The null hypothesis is [tex]H_o : \mu = \$ 59593[/tex]
The alternative hypothesis is [tex]H_a : \mu < \$ 59593[/tex]
The critical value of [tex]\alpha[/tex] from the normal distribution table is [tex]Z_{\alpha } = - 2.33[/tex]
Generally the test statistics is mathematically evaluated as
[tex]t = \frac{\= x - \mu}{ \frac{ \sigma }{ \sqrt{n} } }[/tex]
=> [tex]t = \frac{ 58800 - 59593 }{ \frac{ 1500 }{ \sqrt{30} } }[/tex]
=> [tex]t = -2.896[/tex]
The p-value is obtained from the z-table
[tex]p-value = P(t < -2.896) = 0.0018898[/tex]
Since [tex]p-value < \alpha[/tex] , we reject the null hypothesis, hence it can be concluded that state employees earn on average less than federal employees
Layla is going to drive from her house to City A without stopping. Layla plans to drive
at a speed of 30 miles per hour and her house is 240 miles from City A. Write an
equation for D, in terms of t, representing Layla's distance from City A t hours after
leaving her house.
Answer:
D = 240 - 30t
Step-by-step explanation:
If the equation represents her distance from City A, we need to include 240 in the equation to represent the distance to the city.
Then, we need to subtract 30t from 240 in the equation because 30t represents how far she will have traveled in t hours.
So, D = 240 - 30t is the equation that will represent Layla's distance from the city.
Need help please! what is the total length of a 20 mm steel coiled like a spring with a 16 turns and an outer diameter of 600 mm. pitch is 300 mm. Show your solution please coz i don't really know how to do it! thanks
Answer:
L = 29,550 mm
Step-by-step explanation:
i think i've done this before.. but anyway Lets make it simple and easy.
Let A = 600mm
Let B = 300mm
Let C = 16 as number turns
Let d = 20mm
L = sqrt ((3.14 * (600 - 20))² + 300³) * 16
L = 29,550 mm
Will mark Brainliest! A stick has a length of $5$ units. The stick is then broken at two points, chosen at random. What is the probability that all three resulting pieces are longer than $1$ unit?
Answer:
0.16
Step-by-step explanation:
Length = 5 unitsNumber of broken sticks= 3Equal lengths = 5 units/3See the picture attached for reference.
As you see the best points are the green areas which covers 2 out of 5 zones.
Since it is same for both broken points, the probability of this is:
2/5*2/5 = 4/ 25 = 0.16Answer is 0.16
PLEASE HELP ASAP THANKS IN ADVANCE
Answer:
the answer to the question is "C"
What is the slope of the line shown below?
A.
B.
C.
-
D.
3
Answer:
D
Step-by-step explanation:
Option D is correct. Slope of the line shown in the graph is 3.
The slope of the line is the ratio of the rise to the run, or rise divided by the run.
It describes the steepness of line in the coordinate plane.
The slope intercept form of a line is y=mx+b, where m is slope and b is the y intercept.
The slope of line passing through two points (x₁, y₁) and (x₂, y₂) is
m=(y₂-y₁)/(x₂-x₁)
The line is passing through point (2, 2) and (4, 8).
Lets find the corresponding point values y₂= 8, y₁ = 2, x₂= 4 and x₁ =2.
Plug in the values in slope formula:
Slope = (8-2)/(4-2)
=6/2
=3
Hence, slope of the line shown in the graph is 3. Option D is correct.
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Extensive experience with fans of a certain type used in diesel engines has suggested that the exponential distribution provides a good model for time until failure. Suppose the mean time until failure is 23,100 hours.
(a) What is the probability that a randomly selected fan will last at least 20,000 hours?
What is the probability that a randomly selected fan will last at most 30,000 hours?
What is the probability that a randomly selected fan will last between 20,000 hours and 30,000 hours?
(b) What is the probability that the lifetime of a fan exceeds the mean value by more than 2 standard deviations?
What is the probability that the lifetime of a fan exceeds the mean value by more than 3 standard deviations?
Answer:
0.4207149;0.7271136; 0.3063987; 0.04979 ; 0.01832
Step-by-step explanation:
For an exponential distribution:
IF Mean time until failure = 23100
λ = 1/ 23100 = 0.0000432900
What is the probability that a randomly selected fan will last at least 20,000 hours
x ≥ 20000
P(X ≥ 20000) = 1 - P(X ≤ 20000)
1 - P(X ≤ 20000) = [1 - (1 - e^(-λx))]
1 - P(X ≤ 20000) = [1 - (1 - e^(-0.0000432900*20000)
1 - P(X ≤ 20000) = [1 - (1 - 0.4207148)]
1 - P(X ≤ 20000) = 1 - 0.5792851
1 - P(X ≤ 20000) = 0.4207149
11) What is the probability that a randomly selected fan will last at most 30,000 hours?
x ≤ 30000
P(X ≤ 30000) = 1 - e^(-λx)
P(X ≤ 20000) = 1 - e^(-0.0000432900*30000)
= 1 - e^(−1.2987)
= 1 - 0.2728863
= 0.7271136
111) What is the probability that a randomly selected fan will last between 20,000 hours and 30,000 hours?
0.7271136 - 0.4207149 = 0.3063987
B) What is the probability that the lifetime of a fan exceeds the mean value by more than 2 standard deviations?
More than two standard deviation
X = 23100 + 2(23100) = 23100 + 46200 = 69300
Using the online exponential probability calculator :
P(X > 69300) = 0.04979
C) What is the probability that the lifetime of a fan exceeds the mean value by more than 3 standard deviations?
X = 23100 + 3(23100) = 23100 + 69300 = 92400
P(X > 92400) = 0.01832
A train leaves the station traveling north at 75 mph 2 hours later a second train leaves on a parallel track and travels north at 125 mph how far from the station will they meet
Answer:
At 3 hours, the trains will be equidistant from the station.
Step-by-step explanation:
The first train leaves at 75 miles per hour and has a 2 hour head start. This will put the first train at mile marker 150 (75 * 2) when the second train leaves the station at 125 mph.
To solve when they will be near each other, we set up an equation to solve for t.
150 + 75t = 125t
150 = 50t
3 = t
So given this value, we know the trains will be equidistant from the train station on parallel tracks after 3 hours.
Cheers.
7. The General Society Survey asked a sample of 1200 people how much time they spent watching TV each day. The mean number of hours was 3.0 with a standard deviation of 2.87. A sociologist claims that people watch a mean of 4 hours of TV per day. Do the data provide sufficient evidence to disprove the claim? Use α = .05 to test the hypothesis. a. What are your null and alternative hypotheses? b. What test is appropriate here? Why? c. What is your test statistic? d. What is your critical value? e. What is your final decision: do you reject the null or fail to reject the null?
Answer:
a) and b) Look step by step explanation
c) z(s) = - 12,07
d) z(c) = - 1,64
e) Final decision: Reject H₀
Step-by-step explanation:
We assume Normal Distribution
Data:
Sample population n = 1200
Sample mean μ = 3
Sample Standard deviation 2,87
Claim mean μ₀ = 4
α = 0,05 then from z-table we find z(c) = 1,64 ( critical value )
We need to develop a one tail-test to the left
Test Hypothesis
The General Society developed a survey ( in all cases that is an indication of a sample)
Null hypothesis H₀ μ = μ₀
Alternative hypothesis Hₐ μ < μ₀
To calculate the z(s)
z(s) = ( μ - μ₀ )/ 2,87/√n
z(s) = ( 3 - 4 )/ 2,87/√1200
z(s) = -1 * 34,64 / 2,87
z(s) = - 12,07
To compare z(s) and z(c)
z(s) < z(c) - 12,07 < - 1,64
z(s) is in the rejection region (quite far away) we reject H₀
Data provide enough evidence to disprove the claim
