Answer:
50%
Step-by-step explanation:
Percent change = {(New-Old)/(Old)}*100%
So,
{(45-30)/(40)}*100
=(15/30)*100
=50%
6(5−8v)+12=−54 can you help me with this?
Answer:
v=2
Step-by-step explanation:
6(5-8v)+12=-54
6(5-8v)=-66
(6(5-8v))/6=-66/6
5-8v=-11
-8v=-11-5
-8v=-16
Some transportation experts claim that it is the variability of speeds, rather than the level of speeds, that is a critical factor in determining the likelihood of an accident occurring (Update, Virginia Department of Transportation, Winter 2000). One of the experts claims that driving conditions are dangerous if the variance of speeds exceeds 75 (mph)2. On a heavily traveled highway, a random sample of 55 cars revealed a mean and a variance of speeds of 62.5 mph and 94.7(mph)2, respectively. (You may find it useful to reference the appropriate table: chi-square table or F table)
1. Set up the competing hypothesis to test wxpert,s claim.
2. At the 5% significance level find the critical value and state the decision rule.
3. Can you conclude that driving conditions are dangerous on this highway? explain.
Answer:
Explained below.
Step-by-step explanation:
The claim made by an expert is that driving conditions are dangerous if the variance of speeds exceeds 75 (mph)².
(1)
The hypothesis for both the test can be defined as:
H₀: The variance of speeds does not exceeds 75 (mph)², i.e. σ² ≤ 75.
Hₐ: The variance of speeds exceeds 75 (mph)², i.e. σ² > 75.
(2)
A Chi-square test will be used to perform the test.
The significance level of the test is, α = 0.05.
The degrees of freedom of the test is,
df = n - 1 = 55 - 1 = 54
Compute the critical value as follows:
[tex]\chi^{2}_{\alpha, (n-1)}=\chi^{2}_{0.05, 54}=72.153[/tex]
Decision rule:
If the test statistic value is more than the critical value then the null hypothesis will be rejected and vice-versa.
(3)
Compute the test statistic as follows:
[tex]\chi^{2}=\frac{(n-1)\times s^{2}}{\sigma^{2}}[/tex]
[tex]=\frac{(55-1)\times 94.7}{75}\\\\=68.184[/tex]
The test statistic value is, 68.184.
Decision:
[tex]cal.\chi^{2}=68.184<\chi^{2}_{0.05,54}=72.153[/tex]
The null hypothesis will not be rejected at 5% level of significance.
Conclusion:
The variance of speeds does not exceeds 75 (mph)². Thus, concluding that driving conditions are not dangerous on this highway.
Plot the line for the equation on the graphy,−5=3/2(x−2)
Answer:
The equation of the line is:
y - 5 = 3/2 (x - 2)
Transforming the line into the slope intercept form:
y = 3x/2 - 3 + 5
y = 3x/2 + 2
The slope is 3/2 and the y-intercept is 2.
Plotting this on the graph can be done using these steps:
Locate the point (0,2) on the graph.
From (0,2), count 3 units up and 2 units to the left and indicate that point.
Finally, connect the two points and extend the line.
The ratio of apples to oranges in a basket of fruit is 2:7. There are 21 oranges in the
basket. How many apples are in the basket?
Answer:
6
Step-by-step explanation:
The given ratio specifies the number of apples to be found in the basket
for a given number of oranges.
Correct response:
The number of apples in the basket are 6 applesMethods of calculationThe given ratio of apples to oranges in the basket of fruits = 2:7
The number of oranges = 21 oranges
Required:
The number of apples in the basket.
Solution:
The given ratio can be expressed as follows;
[tex]\mathbf{\dfrac{Number \ of \ apples}{Number \ of \ oranges}} = \dfrac{2}{7} [/tex]Which gives;
[tex]\dfrac{Number \ of \ apples}{21} = \dfrac{2}{7} [/tex]
7 × (Number of apples) = 2 × 21
[tex]Number \ of \ apples = \dfrac{2 \times 21}{7} = 6[/tex]
The number of apples in the basket = 6 applesLearn more about ratios here:
https://brainly.com/question/2645778
what is 917 divided by 63
Answer:
14.55
Step-by-step explanation:
How much of the circle is shaded? Write your answer as a fraction in simplest form.
A box of spaghetti at the grocery store is purchased for $1.60 wholesale and is marked up by 60 percent. Then, the store marks down the item by 20 percent. A customer wants to buy three boxes of spaghetti. How much will the customer pay, including paying 8 percent sales tax? Round your answer to the nearest cent.
Look at the table below.
Steps
Moses’s work
Step 1
1 dollar and 60 cents (1.6) = 2 dollars and 56 cents
Step 2
2 dollars and 56 cents (0.80) = 2 dollars and 5 cents
Step 3
2 dollars and 5 cents (3) = 8 dollars and 20 cents
Step 4
8 dollars and 20 cents (1.08) = 8 dollars and 86 cents
In which step did Moses first make a mistake in his work?
Step 1
Step 2
Step 3
Step 4
Dave cleans pools at a constant rate of 2/5 pools per hr what is the ratio of the number of pools he cleans to the number of hours
How many pools can dave clean in 20 hrs
Answer:
For every 1 hour he cleans 2/5 pools, so the ratio of pools to hours is 0.4:1
In 20 hours, Dave can clean 2/5 • 20 = 8 pools.
GUYS CAN SOMONE anser 2 QUESTIONS!? WHATS 8.97 IN WORD FORM AND EXPANDED FORM!?
Answer:
eight point nine seven, 8+0.9+0.07
Step-by-step explanation:
I mark as brainliest
Answer:
.1
Step-by-step explanation:
Answer:
Point Q is represented by the ordered pair (-2,9)
Brett made a scale drawing of a rectangular room in his house.
The actual length of the room is 12 4/5 ft. The scale used to make the
drawing was 1/4 in. = 1 ft. What is the length, in inches, of the room
on the drawing?
Answer:
Step-by-step explanation:
Length of the room = 12 4/5 ft = 12.8 ft
Scale is 0.25 inches = 1 ft.
This means that every 1ft is shown as 1/4 inch on the map.
To find what 12 4/5ft on the map, you would multiply 12.8 by 0.25.
12.8 x 0.25 = 3.2 inches
What is the quotient of (-55) divide by 5?
Answer:
11
Step-by-step explanation:
✨Answer:✨
-11
✨Step-by-step explanation:✨
-55 ÷ 5 = -11
(Just take the negative sign away and divide)
Question 1
Select ALL expressions that are equivalent to 4x + 2(2x - 5) - (3 - 5x).
A
82 - 10 - 3 - 52
B
3.2 - 13
С
13 – 13
82 - 10 - 3 + 5%
E
83 - 5 - 3 - 5x
Answer:
B
Step-by-step explanation:
pls help thanks alot
Answer:
A, C, D
Step-by-step explanation: the side of the > that has the opening is the side that should have the greater number, so if its like answer A its true
help me with ten please
Answer:
H
Step-by-step explanation:
Angle 3 and angle 4 are supplementary angles angle 3 is 88° what is the measure of angle 4?
Answer:
92°
Step-by-step explanation:
Supplimentary angle = 180°
So, 180° - 88° = 92°
Michelle can type 120 words in 3 minutes. How many words can she type in 1 minute at this rate? A. 30 words B. 40 words C. 50 words D. 60 words
pls answer i cant figure it out pls don't type random things for points
Answer:
B
Step-by-step explanation:
THe answer is b because you have to divide 3 by whatever the answer is so just divide all answers until you get one thats 120 so b
Answer:
B.40 words
Step-by-step explanation:
120÷3=40
40×3=120
The mayor of a town saw an article that claimed the national unemployment rate is 8%. They wondered if this held true in their town, so they took a sample of 200 residents to test H_0 : p = 0.08 versus H_a : p != 0.08, where p is the proportion of residents in the town that are unemployed. The sample included 22 residents who were unemployed.Identify the correct test statistic for this significance test to one decimal place.
Answer:
Z = [tex]\frac{0.11-0.08}{\sqrt{0.08*0.92/200} }[/tex] = 1.6
we reject the Null hypothesis
Step-by-step explanation:
The correct test statistic
Assume :
Null Hypothesis : H_0 : p = 0.08
Alternative hypothesis : H_a : p ≠ 0.08
p = proportion of residents that are unemployed
x = unemployed residents = 22
n = sample size = 200
To get the sample of the population that is unemployed we use this equation
[tex]p = \frac{X}{n}[/tex] = 22 / 200 = 0.11
now we apply the test of of significance of single proportion
= Z = [tex]\frac{p - P}{\sqrt{pq/n} }[/tex]
therefore Z = [tex]\frac{0.11-0.08}{\sqrt{0.08*0.92/200} }[/tex] = 1.6
Therefore we reject the Null hypothesis
Testing the hypothesis, it is found that the test statistic used is z = 1.6.
At the null hypothesis, it is tested if the proportion is of 8%, that is:
[tex]H_0: p = 0.08[/tex]
At the alternative hypothesis, it is tested if the proportion is different of 8%, that is:
[tex]H_1: p \neq 0.08[/tex]
The test statistic is given by:
[tex]z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}[/tex]
In which:
[tex]\overline{p}[/tex] is the sample proportion. p is the proportion tested at the null hypothesis. n is the sample size.For this problem, the parameters are: [tex]p = 0.08, n = 200, \overline{p} = \frac{22}{200} = 0.11[/tex]
Hence, the value of the test statistic is:
[tex]z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}[/tex]
[tex]z = \frac{0.11 - 0.08}{\sqrt{\frac{0.08(0.92)}{200}}}[/tex]
[tex]z = 1.6[/tex]
A similar problem is given at https://brainly.com/question/24166849
Three times a number minus 5 plus the same number
Answer:
15
Step-by-step explanation:
Simplify 5a-(-9)-7a-12
Answer:
-2a = 0 + 3
Step-by-step explanation:
hope this helps.
What is the value of the expression below? (9 divided by 3) + 4 (6 minus 7) –7 –1 7 20
PLEASE ANSWER QUiCK I’m on timer
Answer:
The answer is -1.
Step-by-step explanation:
Answer:
-1 is the answer saw it on clculator
The pilot of an airplane flying at an elevation of 5000 feet sights two towers that are 300 feet apart. If the angle of depression to the tower closer to him is 30, determine the angle of depression to the second tower.
Answer: 29.2 degree
Step-by-step explanation:
Given data:
Elevation of the pilot = 50,000 feet
Elevation of the two towers = 300 feet apart.
Depression of closer tower = 30
Solution:
The angle of depression to the second tower is x
tanx = 5000/(5000*√(3)+300)
x=29.2
Therefore the angle of depression of the second tower is at 29.2 degree
Answer:
29.2°
Step-by-step explanation:
From diagram (b)
Tan θ= opp/adj
Where θ = 30°
opp = 5000ft
adj = ?
tan 30° = 5000/x
x tan30° = 5000
x = 5000/tan 30
x = 5000/0.577
x = 8665.5ft
From diagram c
tan θ = opp/adj
Where θ = ?
opp = 5000
adj = 300+x
x= 8665.5
tan θ = 5000/300+8665.5
tan θ = 5000/8965.5
tan θ = 0.55769
θ = arch tan 0.55769
θ = 29.147
θ= 29.2°
( 3+√3 ) (2+√2) simplify
Which expression would be easier to simplify if you used the commutative property to change the order of the numbers?
A. 30 + (-12) + 70
B. -10 + (-20) + 1/2
C. 60 +40 + (-25)
Answer:it’s A
Step-by-step explanation:
PLEASE HELP I BEG YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
R1: Given
R2: Subtraction Property of Equality
R3: Distribute Property
R4: Addition Property of Equality
R5: Division Property of Equality
Write a paragraph proof for the following conjecture: m∠1 + m∠2 = m∠4
Prove: m∠3 + m∠1 + m∠2 = 180°
Given: ∠1 + ∠2 = ∠ 4
∠4 + ∠3 must be 180° because they are supplementary
If ∠4 + ∠3 is 180, and ∠1 + ∠2 = ∠4, you can substitute ∠4 in the first equation for ∠1 + ∠2.
Hence, we arrive at the answer ∠1 + ∠2 + ∠3 = 180.
Plz mark brainliest:)
The roots of a quadratic equation are
1/ 3 and -2. Determine the equation
Answer: God
Step-by-step explanation:
The reason it’s god is because god created everything so he know everything. So your answer is god
If you spend 540 minutes per year waiting in lines, how many hours is this?
Answer:
540 minutes in hours =540/60
=9 hours
The time 540 minutes in hours will be 9 hours.
What is an expression?The mathematical expression combines numerical variables and operations denoted by addition, subtraction, multiplication, and division signs.
Mathematical symbols can be used to represent numbers (constants), variables, operations, functions, brackets, punctuation, and grouping. They can also denote the logical syntax's operation order and other properties.
Given that the time is 540 minutes. The value of time in hours will be calculated as,
The time of 60 minutes is equal to 1 hour. So divide the time 540 minutes by 60 minutes.
Time = 540 / 60
Time = 9 hours
To know more about an expression follow
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#SPJ2
Round the numbers to the nearest ten thousands.
62 389-
65 405-
51 330-
343 021-
102 779-
Answer:
60,00070,00050,000340,000100,000
Line a passes through points (-2, 1) and (2,9). Write an equation in slope intercept form that is parallel to line a.
Answer:
y=ax+9−2a (i think )
Step-by-step explanation:
A straight line is represented by a linear function
The equation of line a is: [tex]\mathbf{y = 2x +5}[/tex]
The points are given as:
(x1,y1) = (-2,1)
(x2,y2) = (2,9)
Calculate the slope (m)
[tex]\mathbf{m = \frac{y_2 - y_1}{x_2 - x_1}}[/tex]
So, we have:
[tex]\mathbf{m = \frac{9-1}{2--2}}[/tex]
[tex]\mathbf{m = \frac{8}{4}}[/tex]
[tex]\mathbf{m = 2}[/tex]
The equation in slope intercept form is:
[tex]\mathbf{y = m(x - x_1) + y_1}[/tex]
So, we have:
[tex]\mathbf{y = 2(x +2) + 1}[/tex]
[tex]\mathbf{y = 2x +4 + 1}[/tex]
[tex]\mathbf{y = 2x +5}[/tex]
Hence, the equation of line a is: [tex]\mathbf{y = 2x +5}[/tex]
Read more about slope intercept form at:
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I think I know the answer but I just want to double check.
Answer:
D
Step-by-step explanation:
I think it's same with what ur thinking