Weekly wages at a certain factory are
normally distributed with a mean of
$400 and a standard deviation of $50.
Find the probability that a worker
selected at random makes between
$350 and $400.
Answer:
b or a
Step-by-step explanation:
Select the correct answer which expression is equivalent to the product 2x+14/x^2-25 • 8x+40/6x+42
Answer:
A) 8/ 3(x-5)
Step-by-step explanation:
1) 2x+14/x^2-25 • 8x+40/6x+42=2(x+7)/ (x-5)(x+5) * 8(x+5)/ 6(x+7)
2)
after expressing every part of every fraction as product you should reduce the fraction. You can get rid of common divisor (x+5) in the denominator of the first fraction and the numerator of the second one and the common divisor (x+7) for the numerator of the first fraction and denominatorof the second one.
Then you'll get 2*8/ 6(x+5) reduce it again, 2 and 6 have the common divisor 2
Then 8/3(x-5) is the correct answer
Use the following information to answer the next six exercises. There are 23 countries in North America, 12 countries in South America, 47 countries in Europe, 44 countries in Asia, 54 countries in Africa, and 14 in Oceania (Pacific Ocean region).
Let A = the event that a country is in Asia.
Let E = the event that a country is in Europe.
Let F = the event that a country is in Africa.
Let N = the event that a country is in North America. Let O = the event that a country is in Oceania.
Let S = the event that a country is in South America.
18. What is the probability of drawing a red card in a standard deck of 52 cards?
19. What is the probability of drawing a club in a standard deck of 52 cards?
The probabilities we found in this exercise are.
0.2268 = 22.68% probability that a country is in Asia.0.2423 = 24.23% probability that a country is in Europe.0.2784 = 27.84% probability that a country is in Africa.0.1186 = 11.86% probability that a country is in North America.0.0722 = 7.22% probability that a country is in Oceania.0.0619 = 6.19% probability that a country is in South America.0.5 = 50% probability of drawing a red card in a standard deck of 52 cards.0.25 = 25% probability of drawing a club in a standard deck of 52 cards.In this exercise, probability concepts are used.
A probability is the number of desired outcomes divided by the number of total outcomes.
Total number of countries:
23 + 12 + 47 + 44 + 54 + 14 = 194
Let A = the event that a country is in Asia.
44 of the 194 countries are in Asia, thus:
[tex]P(A) = \frac{44}{194} = 0.2268[/tex]
0.2268 = 22.68% probability that a country is in Asia.
Let E = the event that a country is in Europe.
47 out of 194 countries are in Europe, thus:
[tex]P(E) = \frac{47}{194} = 0.2423[/tex]
0.2423 = 24.23% probability that a country is in Europe.
Let F = the event that a country is in Africa.
54 out of 194 countries are in Africa, thus:
[tex]P(F) = \frac{54}{194} = 0.2784[/tex]
0.2784 = 27.84% probability that a country is in Africa.
Let N = the event that a country is in North America.
23 out of 194 countries are in North America, thus:
[tex]P(N) = \frac{23}{194} = 0.1186[/tex]
0.1186 = 11.86% probability that a country is in North America.
Let O = the event that a country is in Oceania.
14 out of 194 countries are in Oceania, thus:
[tex]P(O) = \frac{14}{194} = 0.0722[/tex]
0.0722 = 7.22% probability that a country is in Oceania.
Let S = the event that a country is in South America.
12 out of 194 countries are in South America, thus:
[tex]P(S) = \frac{12}{194} = 0.0619[/tex]
0.0619 = 6.19% probability that a country is in South America.
18. What is the probability of drawing a red card in a standard deck of 52 cards?
In a standard deck of 52 cards, 26 are red, and thus:
[tex]p = \frac{26}{52} = 0.5[/tex]
0.5 = 50% probability of drawing a red card in a standard deck of 52 cards.
19. What is the probability of drawing a club in a standard deck of 52 cards?
In a standard deck of 52 cards, 13 are clubs, and thus:
[tex]p = \frac{13}{52} = 0.25[/tex]
0.25 = 25% probability of drawing a club in a standard deck of 52 cards.
For more about probabilities, you can check https://brainly.com/question/24104122
If there is a maximum of 4,000 hours of labor available per month and 300 ping-pong balls (x1) or 125 wiffle balls (x2) can be produced per hour of labor, which of the following constraints reflects this situation?
a. 300x1 + 125x2 > = 4,000
b. 300x1 + 125x2 < = 4,000
c. 425(x1 + x2) < = 4,000
d. 300x1 + 125x2 = 4,000
Answer:
b. 300x1 + 125x2 < = 4,000
Step-by-step explanation:
Maximum of 4,000 hours
This means that the the total amount of labor has to be of at most 4,000, that is:
[tex]T \leq 4000[/tex]
300 ping-pong balls (x1) or 125 wiffle balls (x2) can be produced per hour of labor
The total amount of labor is:
[tex]T = 300x1 + 125x2[/tex]
Uniting the two equations:
[tex]T \leq 4000[/tex]
[tex]300x1 + 125x2 \leq 4000[/tex]
And thus the correct answer is given by option b.
Which of the relations given by the following sets of ordered pairs is a function?
o {(5,2), ( - 4, 2), (3,6), (0,4), (- 1, 2)}
o {(5, 4), (5, 6), (5,8), (5, 10), (5, 12)}
{(-3, - 2), ( - 2, – 1), (0, - 1), (0, 1), (1, 2)}
{(7,3), ( – 6,8), ( – 3,5), (0, – 3), (7, 11)}
9514 1404 393
Answer:
(a) {(5, 2), (-4, 2), (3, 6), (0, 4), (-1, 2)}
Step-by-step explanation:
The only relation with no repeated x-values is the first one. The first relation is a function.
Jenny has borrowed K2500from a bank at 9.25% p.a. invested for 185 days. How much will she pay back to the bank?
Answer:
115.625
PRT/100
Find the following integral
There's nothing preventing us from computing one integral at a time:
[tex]\displaystyle \int_0^{2-x} xyz \,\mathrm dz = \frac12xyz^2\bigg|_{z=0}^{z=2-x} \\\\ = \frac12xy(2-x)^2[/tex]
[tex]\displaystyle \int_0^{1-x}\int_0^{2-x}xyz\,\mathrm dz\,\mathrm dy = \frac12\int_0^{1-x}xy(2-x)^2\,\mathrm dy \\\\ = \frac14xy^2(2-x)^2\bigg|_{y=0}^{y=1-x} \\\\= \frac14x(1-x)^2(2-x)^2[/tex]
[tex]\displaystyle\int_0^1\int_0^{1-x}\int_0^{2-x}xyz\,\mathrm dz\,\mathrm dy\,\mathrm dx = \frac14\int_0^1x(1-x)^2(2-x)^2\,\mathrm dx[/tex]
Expand the integrand completely:
[tex]x(1-x)^2(2-x)^2 = x^5-6x^4+13x^3-12x^2+4x[/tex]
Then
[tex]\displaystyle\frac14\int_0^1x(1-x)^2(2-x)^2\,\mathrm dx = \left(\frac16x^6-\frac65x^5+\frac{13}4x^4-4x^3+2x^2\right)\bigg|_{x=0}^{x=1} \\\\ = \boxed{\frac{13}{240}}[/tex]
a motercycle can travel 60 miles per gallon. approximently how many gallons of fuel will the motercycle need to travel 40 km
[1 mile = 1.6km]
Answer:
Step-by-step ex0.72
(x+16)²=12 plz help me and show work
Answer:
The answer is [tex]x=-16[/tex] ±[tex]2\sqrt{3}[/tex] in exact form or [tex]x=-12.535898[/tex], [tex]x=-19.464102[/tex] in decimal form.
Step-by-step explanation:
To solve this problem, start by moving all terms to the left side of the equation and simplify. Simplify the equation by subtracting 12 from both sides of the equation and squaring [tex]x+16[/tex], which will look like [tex]x^{2} +32x+256-12=0[/tex]. Next, simplify the equation again, which will look like [tex]x^{2} +32x+244=0[/tex].
Then, use the quadratic formula to find the solutions. The quadratic formula looks like[tex]\frac{-b(+-)\sqrt{b^{2}-4ac } }{2a}[/tex].
For this problem, the quadratic variables are as follows:
[tex]a=1[/tex]
[tex]b=32[/tex]
[tex]c=244[/tex]
The next step is to substitute the values [tex]a=1[/tex], [tex]b=32[/tex], and [tex]c=244[/tex] into the quadratic formula and solve. The quadratic formula will look like [tex]\frac{-32(+-)\sqrt{32^2-4(1*244)} }{2*1}[/tex]. To simplify the equation, start by simplifying the numerator, which will look like [tex]x=\frac{-32(+-)4\sqrt{3} }{2*1}[/tex]. Then, multiply 2 by 1 and simplify the equation, which will look like [tex]x=-16(+-)2\sqrt{3}[/tex]. The final answer is [tex]x=-16[/tex] ±[tex]2\sqrt{3}[/tex] in exact form. In decimal form, the final answer is [tex]x=-12.535898[/tex], [tex]x=-19.464102[/tex].
A hose is left running for 240 minutes to 2 significant figures. The amount of water coming out of the hose each minute is 2.1 litres to 2 significant figures. Calculate the lower and upper bounds of the total amount of water that comes out of the hose.
Answer:
Hello,
Step-by-step explanation:
Let say t the time the hose is left running
235 ≤ t < 245 (in min)
Let say d the amount of water coming out of the hose each minute
2.05 ≤ d < 2.15 (why d : débit in french)
235*2.05 ≤ t*d < 245*2.15
481.75 ≤ t*d < 526.75 (litres)
Answer:
Lower bound: [tex]495\; \rm L[/tex] (inclusive.)
Upper bound: [tex]505\; \rm L[/tex] (exclusive.)
Step-by-step explanation:
The amount of water from the hose is the product of time and the rate at which water comes out.
When multiplying two numbers, the product would have as many significant figures as the less accurate factor.
In this example, both factors are accurate to two significant figures. Hence, the product would also be accurate to two significant figures. That is:
[tex]240 \times 2.1 = 5.0 \times 10^{2}\; \rm L[/tex] ([tex]500\; \rm L[/tex] with only two significant figures.)
Let [tex]x[/tex] denote the amount of water in liters. For [tex]x\![/tex] to round to [tex]5.0 \times 10^{2}\; \rm L[/tex] only two significant figures are kept, [tex]495 \le x < 505[/tex]. That gives a bound on the quantity of water from the hose.
During a test period, an experimental group of 10 vehicles using an 85 percent ethanol-gasoline mixture showed mean CO2 emissions of 667 pounds per 1000 miles, with a standard deviation of 20 pounds. A control group of 14 vehicles using regular gasoline showed mean CO2 emissions of 679 pounds per 1000 miles with a standard deviation of 15 pounds. At α = 0.05, in a left-tailed test (assuming equal variances) the test statistic is:______.
A. 1.321.
B. -2.508.
C. -2.074.
D. -1.717.
Answer:
-1.683
Step-by-step explanation:
Given :
Group 1 :
x1 = 667 ; n1 = 10 ; s1 = 20
Group 2 :
x2 = 679 ; n2 = 14 ; s2 = 15
The test statistic assuming equal variance :
x1 - x2 / √[Sp² * (1/n1 + 1/n2)]
sp² = [(n1 - 1)*s1² + (n2 - 1)*s2²] ÷ (n1 + n2 - 2)
Sp² = [(10 - 1)*20² + (14 - 1)*15²] = 296.59
Test statistic =
(667 - 679)/ √[296.59 * (1/10 + 1/14)]
-12 / 7.1304978
Test statistic = - 1.682
Here's the result of this question
The point (-2,7) has undergone the following transformations:
1. Translated 1 unit up and 4 units left
Then
2. Reflected about the c-axis
Then
3. Rotated 90° anticlockwise about the origin
A) Its final coordinates are (3,-1)
B) Its final coordinates are (8,-6)
C) Its final coordinates are (-8,6)
D) Its final coordinates are (-3,1)
Answer:
B) Its final coordinates are (8,-6)
Step-by-step explanation:
1. Translated 1 unit up and 4 units left
(-2,7) becomes (-6, 8)
2. Reflected about the x-axis
(-6,8) becomes (-6, -8)
3. Rotated 90° anticlockwise about the origin
(-6, -8) becomes (8, -6) because when rotating 90 degrees anticlockwise about the origin, point A (x,y) becomes point A' (-y,x). In other words, switch the x and y and make y negative.
Suppose your Unit Quiz grades have been: 85%, 80%, 96%, 72%, 78%, 85% and 92%
a) What is your average/mean score?
b) What is the median score?
c) What is the mode score?
d) Why is the mean lower than the median?
e) What will your mean be if you get a perfect score of 100% on your next quiz?
Answer:
mean: 84
median: 85
mode: 85
explainations for d and e below.
Step-by-step explanation:
mean:
(85+80+96+72+78+85+92)/7 = 544/7 = 84
median:
sort them in order from least to greatest first
72, 78, 80, 85, 85, 92, 96
find the middle number in that order, that's your median. in this case, it's 85.
mode:
number that appears the most in the order; the frequency. in this case as well, it's also 85.
answer for d:
the reason why the mean is lower than the median is because of the fact we were figuring out the average and had to divide, unlike the median where it's just the middle of the order we have.
answer for e:
(85+80+96+72+78+85+92+100)/8 = 644/8 = 80.5%
p.s: please subscribe to #gauthmath# sub reddit if you can for more help.
What is the domain of the function?
Answer: The answer is -2
Step-by-step explanation:
that is where the line starts
hope this helped
Answer:
x > -2
Step-by-step explanation:
The domain is the values that the input can take
x goes from -2( not including -2) to infinity
x > -2
Determine whether the following polygons are similar. If yes, type 'yes' in the Similar box and type in the similarity statement and scale factor. If no, type 'None' in the blanks. For the scale factor, please enter a fraction. Use the forward dash (i.e. /) to create a fraction (e.g. 1/2 is the same as 12
1
2
).
Given:
The figures of two polygons.
To find:
Whether the polygons are similar and then find the scale factor (if similar).
Solution:
From the given figures it is clear that both polygons are rectangles and their all interior angles are right angles.
The ratio of their longer sides:
[tex]\dfrac{32}{26}=\dfrac{16}{13}[/tex]
The ratio of their shorter sides:
[tex]\dfrac{18}{12}=\dfrac{3}{2}[/tex]
Since the ratio of their corresponding sides are not equal, therefore the two polygons are not similar.
Therefore the required solutions are:
Similar : No
Similarity statement : None
Scale factor : None
Find the missing side lengths leave your answer as a racials simplest form
Answer:
x = 20
y = 10
it's a 30-60-90 triangle
The degree of the polynomial function f(x) is 4. The roots of the equation f(x) =0 are -2,-1,1 and 3. Which graph could be the graph of f(x)?
Answer:
top right
Step-by-step explanation:
roots of an equation = x-intercepts
Answer:
top right is the answer from my calculatins
A projectile is fired from a cliff feet above the water at an inclination of 45° to the horizontal, with a muzzle velocity of feet per second. The height h of the projectile above the water is given by
where x is the horizontal distance of the projectile from the face of the cliff. Use this information to answer the following.
(a) At what horizontal distance from the face of the cliff is the height of the projectile a maximum?
(Simplify your answer.)
(b) Find the maximum height of the projectile.
(Simplify your answer.)
(c) At what horizontal distance from the face of the cliff will the projectile strike the water?
(d) Using a graphing utility, graph the function h, Which of the following shows the graph of h(x)?
In all graphs, the window is by
A.
A coordinate system has a horizontal axis labeled from 0 to 230 in increments of 20 and a vertical axis labeled from 0 to 260 in increments of 50. From left to right, a curve starts at (0, 180), rises to a maximum at (74, 230), and then falls to (230, 10). All coordinates are approximate.
B.
A coordinate system has a horizontal axis labeled from 0 to 230 in increments of 20 and a vertical axis labeled from 0 to 260 in increments of 50. From left to right, a curve starts at (0, 210), rises to a maximum at (40, 230), and then falls to (176, 0). All coordinates are approximate.
C.
A coordinate system has a horizontal axis labeled from 0 to 230 in increments of 20 and a vertical axis labeled from 0 to 260 in increments of 50. From left to right, a curve starts at (0, 210), rises to a maximum at (56, 240), and then falls to (220, 0). All coordinates are approximate.
D.
A coordinate system has a horizontal axis labeled from 0 to 230 in increments of 20 and a vertical axis labeled from 0 to 260 in increments of 50. From left to right, a curve starts at (0, 240), rises to a maximum at (28, 245), and then falls to (194, 0). All coordinates are approximate.
(e) When the height of the projectile is 100 feet above the water, how far is it from the cliff?
Answer:
$170 Feet
Step-by-step explanation:
It is very long process
A psychologist conducted a survey of the attitude towards the sustainability of American energy consumption with 250 randomly selected individuals several years ago. The psychologist believes that these attitudes have changed over time. To test this he randomly selects 250 individuals and asks them the same questions. Can the psychologist confirm his theory that the attitudes have changed from the first survey to the second survey?
Attitude 1st Survey 2nd Survey
Optimistic 7% 6%
Slightly Optimistic 9% 6%
Slightly Pessimistic 31% 37%
Pessimistic 53% 51%
Step 4 of 10: Find the expected value for the number of respondents who are optimistic. Round your answer to two decimal places.
Answer:
Yes. the Psychologist can confirm his theory that the attitudes have changed over time, based on the first and second surveys.
The expected value for the number of respondents who are optimistic is:
= 16.25
Step-by-step explanation:
Attitude 1st Survey 2nd Survey
Optimistic 7% 6%
Slightly Optimistic 9% 6%
Slightly Pessimistic 31% 37%
Pessimistic 53% 51%
Expected value of optimistic respondents:
Attitude
Optimistic Expected Value
1st Survey 8.75 (250 * 7% * 50%)
2nd Survey 7.50 (250 * 6% * 50%)
Total EV 16.25
Suppose that, in the past, 40% of all adults favored capital punishment. Do we have reason to believe that the proportion of adults favoring capital punishment today has increased if, in a random sample of 15 adults, 8 favor capital punishment? Use a 0.05 level of significance.
Answer:
The p-value of the test is 0.1469 > 0.05, which means that there is no reason to believe that the proportion of adults favoring capital punishment today has increased, using a 0.05 level of significance.
Step-by-step explanation:
Suppose that, in the past, 40% of all adults favored capital punishment. Test if the proportion has increased:
At the null hypothesis, we test if the proportion is still of 40%, that is:
[tex]H_0: p = 0.4[/tex]
At the alternative hypothesis, we test if the proportion has increased, that is, is greater than 40%, so:
[tex]H_1: p > 0.4[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
0.4 is tested at the null hypothesis:
This means that [tex]\mu = 0.4, \sigma = \sqrt{0.4*0.6}[/tex]
Random sample of 15 adults, 8 favor capital punishment.
This means that [tex]n = 15, X = \frac{8}{15} = 0.5333[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{0.5333 - 0.4}{\frac{\sqrt{0.4*0.6}}{\sqrt{15}}}[/tex]
[tex]z = 1.05[/tex]
P-value of the test and decision:
The p-value of the test is the probability of finding a sample proportion of 0.5333 or more, which is 1 subtracted by the p-value of z = 1.05.
Looking at the z-table, z = 1.05 has a p-value of 0.8531.
1 - 0.8531 = 0.1469.
The p-value of the test is 0.1469 > 0.05, which means that there is no reason to believe that the proportion of adults favoring capital punishment today has increased, using a 0.05 level of significance.
Megan and Suzanne each have a plant. They track the growth of their plants for four weeks.
Whose plant grew at a faster rate, and what was the rate?
Suzanne’s at 2 inches per week
Suzanne’s at 1.5 inches per week
Megan’s at 3 inches per week
Megan’s at 2.5 inches per week
Answer:
Megan’s at 2.5 inches per week
make m the subject of this eequation please help!! asap
Answer: [tex]M = \pm\sqrt{\frac{3K}{4(5+7NK)}}\\\\[/tex]
======================================
Work Shown:
[tex]\frac{5}{K} = \frac{3}{4M^2} - 7N\\\\\frac{5}{K}+7N = \frac{3}{4M^2}\\\\\frac{5}{K}+7N*\frac{K}{K} = \frac{3}{4M^2}\\\\\frac{5}{K}+\frac{7NK}{K} = \frac{3}{4M^2}\\\\\frac{5+7NK}{K} = \frac{3}{4M^2}\\\\4M^2*(5+7NK) = K*3\\\\M^2 = \frac{3K}{4(5+7NK)}\\\\M = \pm\sqrt{\frac{3K}{4(5+7NK)}}\\\\[/tex]
Other forms are possible, but those forms would be equivalent to what is shown above.
Solve by elimination.
16x – 8y = 16
8x – 4y = 8
A. infinite number of solutions
B. (-2,-5)
c. (-20, -4)
R. (2,0)
Answer:
Step-by-step explanation:
16x-8y = 16 ⇒ 8x - 4y = 8, which is identical to the second equation.
The equations are equivalent, so there are an infinite number of solutions.
Researchers studied symptom distress and palliative care designation among a sample of 710 hospitalized patients. Controlling for age, they used a t-test to compare average distress from nausea scores in men and women. Lower scores indicated less distress from nausea. They report men had an average score of 1.02 and woman had an average score of 1.79. Which statement is correct?
(2pts)
Select Men had significantly less distress from nausea. as your answer
Men had significantly less distress from nausea.
Select Men had half as much distress from nausea as woman but we can not determine if this is a significant difference. as your answer
Men had half as much distress from nausea as woman but we can not determine if this is a significant difference.
Select Men had less distress from nausea on average than women but we can not determine if this is a significant difference. as your answer
Men had less distress from nausea on average than women but we can not determine if this is a significant difference.
Select There is a positive correlation between distress from nausea and gender. as your answer
There is a positive correlation between distress from nausea and gender.
Answer:
A. Men had less distress from nausea on average than women but we can not determine if this is a significant difference.
Step-by-step explanation:
Working based on the information given, the mean values of each group with with men having an average score of 1.02 and women have an average of 1.79 this reveals that distressing nausea on average is higher in women than in men . However, to test if there is a significant difference would be challenging as the information given isn't enough to make proceed with the test as the standard deviations of the two groups aren't given and no accompanying sample data is given.
You are playing a game by drawing a card from a standard deck and replacing it. If the card is a face card, you win $30. If it is not a face card, you pay $2. There are 12 face cards in a deck of 52 cards. What is the expected value of playing the game
92 cardsㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤ
ㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤ
ㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤ
ㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤ
ㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤ
How are the functions y = x and y = x+ 5 related? How are their graphs related?
a. Each output for y = x + 5 is 5 less than the corresponding output for y = x.
The graph of y = x+ 5 is the graph of y = x translated down 5 units.
b. Each output for y = x+ 5 is 5 more than the corresponding output for y = x.
The graph of y = x+ 5 is the graph of y = x translated up 5 units.
Each output for y = x+5 is 5 more than the corresponding output for y = x.
The graph of y = x+5 is the graph of y = x translated down 5 units.
d. Each output for y = x + 5 is 5 less than the corresponding output for y=x.
Answer:
b
Step-by-step explanation:
the graph gets translated 5 units above its parent graph of y = x
Many freeways have service (or logo) signs that give information on attractions, camping, lodging, food, and gas services prior to off-ramps. These signs typically do not provide information on distances. An article reported that in one investigation, six sites along interstate highways where service signs are posted were selected. For each site, crash data was obtained for a three-year period before distance information was added to the service signs and for a one-year period afterward. The number of crashes per year before and after the sign changes were as follows.
Before 13 22 65 123 56 63
After 14 21 43 84 75 72
1. The article included the statement "A paired t-test was performed to determine whether there was any change in the mean number of crashes before and after the addition of distance information on the signs." Carry out such a test. (Note: The relevant normal probability plot shows a substantial linear pattern.)
a. State and test the appropriate hypotheses. (Use α = 0.05.)
b. Calculate the test statistic and P-value. (Round your test statistic to two decimal places and your P-value to three decimal places.)
t = _____
p-value = _____
c. State the conclusion in the problem context.
A. Fail to reject H0. The data does not suggest a significant mean difference in the average number of accidents after information was added to road signs.
B. Reject H0. The data suggests a significant mean difference in the average number of accidents after information was added to road signs.
C. Fail to reject H0. The data suggests a significant mean difference in the average number of accidents after information was added to road signs.
D. Reject H0. The data does not suggest a significant mean difference in the average number of accidents after information was added to road signs.
2. If a seventh site were to be randomly selected among locations bearing service signs, between what values would you predict the difference in the number of crashes to lie? (Use a 95% prediction interval. Round your answers to two decimal places.)
Answer:
Test statistic = 0.63
Pvalue = 0.555
A. Fail to reject H0. The data does not suggest a significant mean difference in the average number of accidents after information was added to road signs.
Step-by-step explanation:
Given :
Before 13 22 65 123 56 63
After_ 14 21 43 84 75 72
To perform a paired t test :
H0 : μd = 0
H1 : μd ≠ 0
We obtain the difference between the two dependent sample readings ;
Difference, d = -1, 1, 22, 39, -19, -9
The mean of difference, Xd = Σd/ n = 33/6 = 5.5
The standard deviation, Sd = 21.296 (calculator).
The test statistic :
T = Xd ÷ (Sd/√n) ; where n = 6
T = 5.5 ÷ (21.296/√6)
T = 5.5 ÷ 8.6940555
T = 0.6326
The Pvalue : Using a Pvalue calculator ;
df = n - 1 = 6 - 1 = 5
Pvalue(0.6326, 5) = 0.5548
Decision region :
Reject H0 ; If Pvalue < α; α = 0.05
Since 0.5548 > 0.05 ; we fail to reject the Null and conclude that the data does not suggest a significant mean difference in the average number of accidents after information was added to road signs.
When A = 200, solve the equation x2 - 40x + A=0 using the quadratic formula. Show all your working and give your answers correct to 2 decimal places.
Answer:
Solution given:
equation is:
x²-40x+A=0
when A=200
equation becomes
x²-40x+200=0
Comparing above equation with ax²+bx+c=0 we get
a=1
b=-40
c=200
By using quadratic equation formulax=[tex]\displaystyle \frac{-b±\sqrt{b²-4ac}}{2a}[/tex]
substituting value
x=[tex]\displaystyle \frac{-*-40±\sqrt{(-40)²-4*1*200}}{2*1}[/tex]
x=[tex]\displaystyle \frac{40±\sqrt{800}}{2}[/tex]
x=[tex]\displaystyle \frac{40±20\sqrt{2}}{2}[/tex]
taking positive
x=[tex]\displaystyle \frac{40+20\sqrt{2}}{2}[/tex]
x=34.14
taking negative
x=[tex]\displaystyle \frac{40-20\sqrt{2}}{2}[/tex]
x=5.86
x=34.14 or 5.86Given that 3y = x + 6 and y = kx + 12 are perpendicular, find the value of k
k = -3
Step-by-step explanation:
Let's rewrite the equations in their slope-intercept forms:
[tex]y = \frac{1}{3}x + 2\:\:\:\:\:\:\:(1)[/tex]
[tex]y = kx + 12\:\:\:\:\:(2)[/tex]
In order for Eqn(2) to be perpendicular to Eqn(1), the slope of Eqn(2) must be the negative reciprocal of that of Eqn(1). Therefore, [tex]k = -3[/tex].
If (-2, y) lies on the graph of y = 3Y, then y =
Answer:
[tex]\displaystyle \frac{1}{9}[/tex]
Step-by-step explanation:
Hi there!
This question is asking us what the value of y is when x is -2, hence the point (-2,y).
[tex]y=3^x[/tex]
To find y, replace x in the equation with -2 and evaluate:
[tex]y=3^-^2[/tex]
When [tex]a^-^n[/tex] where n>0, [tex]a^-^n=\displaystyle \frac{1}{a^n}[/tex]:
[tex]y=\displaystyle \frac{1}{3^2} \\\\y=\displaystyle \frac{1}{9}[/tex]
I hope this helps!
