Answer:
a
See in the explanation
a-2.
Discrete
b-1.
Mean = 4.201
Standard Deviation = 2.069
b-2.
4.201
c.
Mean = 16.153
Standard Deviation = 8.079
Step-by-step explanation:
Given Data:
Number of Hours Frequency Amount Charged
1 16 $3
2 34 6
3 51 12
4 39 16
5 34 21
6 16 24
7 9 27
8 30 29
∑f = 229
a. Convert the information on the number of hours parked to a probability distribution:
The probability is calculated by dividing each frequency by 229. For example probability of Hour 1 is calculated as:
16 / 229 = 0.06987
This way all the hours probabilities are computed. The probability distribution is given below
Hours Probability
1 0.06987
2 0.14847
3 0.2227
4 0.1703
5 0.1485
6 0.0699
7 0.0393
8 0.1310
∑ 1
a-2. Is this a discrete or a continuous probability distribution?
This is a discrete probability distribution as the probability of each hour of between 0 and 1 and the sum of all the probabilities of hours is 1.
b-1. Find the mean and the standard deviation of the number of hours parked.
First multiply each value of Number of hours by the corresponding frequency. Let x represents the number of hours and f represents frequency. Then:
Number of Hours Parked
fx
16
68
153
156
170
96
63
240
Now add the above computed products.
∑fx = 16+68+153+156+170+96+63+240 = 962
Compute Mean:
Now the formula to calculate mean:
Mean = Sum of the value / Number of value
= ∑fx / ∑f
= 962 / 229
Mean = 4.201
Compute Standard Deviation:
Let x be the Number of hours.
Let f be the frequency
First calculate (x-x_bar) where x is each number of hours and x_bar is mean. The value of x_bar i.e. [tex]\frac{}{x}[/tex] = 4.201
For example for the Hour = 1 , and mean = 4.201
Then (x-[tex]\frac{}{x}[/tex]) = 1 - 4.201 = -3.201
So calculating this for every number of hour we get:
(x-[tex]\frac{}{x}[/tex])
-3.201
-2.201
-1.201
-0.201
0.799
1.799
2.799
3.799
Next calculate (x-[tex]\frac{}{x}[/tex])². Just take the squares of the above column (x-[tex]\frac{}{x}[/tex])
For example the first entry of below calculation is computed by:
(x-[tex]\frac{}{x}[/tex])² = (-3.201 )² = 10.246401
(x-[tex]\frac{}{x}[/tex])²
10.246401
4.844401
1.442401
0.040401
0.638401
3.236401
7.834401
14.432401
Next multiply each entry of (x-[tex]\frac{}{x}[/tex])² with frequency f. For example the first entry below is computed by:
(x-[tex]\frac{}{x}[/tex])² * f = 10.246401 * 16 = 163.942416
(x-[tex]\frac{}{x}[/tex])² * f
163.942416
164.709634
73.562451
1.575639
21.705634
51.782416
70.509609
432.97203
Now the formula to calculate standard deviation is:
S = √∑(x-[tex]\frac{}{x}[/tex])² * f/n
Here
n = ∑f = 229
∑(x-[tex]\frac{}{x}[/tex])² * f is the sum of all entries of (x-[tex]\frac{}{x}[/tex])² * f
∑(x-[tex]\frac{}{x}[/tex])² * f = 980.759829
S = √∑(x-[tex]\frac{}{x}[/tex])² * f/n
= √980.759829 / 229
= √4.2827940131004
= 2.0694912449924
S = 2.069
b-2) How long is a typical customer parked?
That is the value of mean calculated in part b-1. Hence
Typical Customer Parked for 4.201 hours
c) Find the mean and the standard deviation of the amount charged.
First multiply each value of Amount Charged by the corresponding frequency. Let x represents the number of hours and f represents frequency. Then:
fx
48
204
612
624
714
384
243
870
Now add the above computed products.
∑fx = 48+204+612+624+714+384+243+870 = 3699
Compute Mean:
Now the formula to calculate mean:
Mean = Sum of the value / Number of value
= ∑fx / ∑f
= 3699 / 229
Mean = 16.153
Compute Standard Deviation:
Let x be the Amount Charged.
Let f be the frequency.
First calculate (x-x_bar) where x is each value of Amount charged and x_bar is mean. The value of x_bar i.e. [tex]\frac{}{x}[/tex] = 16.153
For example for the Amount Charged = 3 , and mean = 16.153
Then (x-[tex]\frac{}{x}[/tex]) = 3 - 16.153 = -13.153
So calculating this for every number of hour we get:
(x-[tex]\frac{}{x}[/tex])
-13.153
-10.153
-4.153
-0.153
4.847
7.847
10.847
12.847
Next calculate (x-[tex]\frac{}{x}[/tex])². Just take the squares of the above column (x-[tex]\frac{}{x}[/tex])
For example the first entry of below calculation is computed by:
(x-[tex]\frac{}{x}[/tex])² = (-13.153 )² = 173.001409
(x-[tex]\frac{}{x}[/tex])²
173.001409
103.083409
17.247409
0.023409
23.493409
61.575409
117.657409
165.045409
Next multiply each entry of (x-[tex]\frac{}{x}[/tex])² with frequency f. For example the first entry below is computed by:
(x-[tex]\frac{}{x}[/tex])² * f = 173.001409 * 16 =
(x-[tex]\frac{}{x}[/tex])² * f
2768.022544
3504.835906
879.617859
0.912951
798.775906
985.206544
1058.916681
4951.36227
∑(x-[tex]\frac{}{x}[/tex])² = 14947.65066
Now the formula to calculate standard deviation is:
S = √∑(x-[tex]\frac{}{x}[/tex])² * f/n
Here
n = ∑f = 229
∑(x-[tex]\frac{}{x}[/tex])² * f is the sum of all entries of (x-[tex]\frac{}{x}[/tex])² * f
∑(x-[tex]\frac{}{x}[/tex])² * f = 14947.65066
S = √∑(x-[tex]\frac{}{x}[/tex])² * f/ ∑f
= √65.273583668122
= 8.0792068712295
S = 8.079
Emma rents a car from a company that rents cars by the hour. She has to pay an initial fee of $75, and then they charge her $9 per hour. Write an equation for the total cost if Emma rents the car for ℎ hours. If Emma has budgeted $250 for the rental cars, how many hours can she rent the car? Assume the car cannot be rented for part of an hour.
These figures are similar. The area of one is given. Find the area of the other. PLZ HELP
Answer: 6
Step-by-step explanation:
Solve the right triangle.
a = 3.3 cm, b = 1.7 cm, C = 90°
Round values to one decimal place.
Answer:
A = 62.7°B = 27.3°c = 3.7Step-by-step explanation:
tan(A) = a/b = 3.3/1.7
A = arctan(33/17) ≈ 62.7°
B = 90° -A = 27.3°
c = √(a²+b²) = √(3.3² +1.7²) = √13.78
c ≈ 3.7
Suppose you are standing such that a 32-foot tree is directly between you and the sun. If you are standing 140 feet away from the tree and the tree casts a 160-foot shadow, how tall could you be and still be completely in the shadow of the tree? x 160 ft 140 ft 32 ft
Answer:
Height = 4 feet
Step-by-step explanation:
To determine how tall I can be we take the difference between the shadow cast by the 32-feet tree and the distance away from the tree
But the tree is 32 feet tall but on shadow it's 160
So lemme determine how long I'll be in my shadow first
Distance away from tree= 140 feet
Length of shadow cast by tree
= 160 feet
Length of shadow= 160-140
Length if shadow= 20 feet
My height= x
X/20= 32/160
X= 20*32/260
X = 4 feet
Height = 4 feet
What is the first step in mathematical induction?
Answer:
Show that the statement is true for n=1
Step-by-step explanation:
Hey,
Show that the statement is true for n=1
You can check my other answer there which explains a little bit more the ideas.
https://brainly.com/question/17162256
thank you
1 - Dada a função f(x)= -Ix²-5x+4I, determine o valor de função para x = -1. * 1 ponto a) -10 b) 10 c) 9 d) -9 e) -8
Option a) -10
[tex] f(x)=-|x^2-5x+4|[/tex]
put $x=-1$
$f(-1)=-|(-1)^2-5(-1)+4|$
$\implies f(-1)=-|1+5+4|=-|10|=10$
Answer:
option a
Step-by-step explanation:
Option a) -10
put $x=-1$
$f(-1)=-|(-1)^2-5(-1)+4|$
$\implies f(-1)=-|1+5+4|=-|10|=10$
At a baby shower, 15 guests are in attendance and 4 of them are randomly selected to receive a door prize. If all 4 prizes are identical, in how many ways can the prizes be awarded?
Answer:
1365
Step-by-step explanation:
We figure out combinations using this formula: n!
r!(n-r)!
n=15
r=4
So n!= 15x14x13x12x11x0x9x8x7x6x5x4x3x2x1
r! = 4x3x2x1 times 15-4!, which is 11! = 11x10x9x8x7x6x5x4x3x2x1
Put this together and you have 15x14x13x12/4x3x2x1=
There are 1365 different ways to award the 4 door prizes to 4 guests from a group of 15 guests.
What are the Combinations?Combinations are the procedures used in mathematics to pick k things from n different items without replacement.
The following formula computes the combinations of k items from n:
(n, k) = n! / k!×(n-k)!
The number of ways to award the 4 door prizes to 4 guests out of a group of 15 guests is a combinatorial problem that can be calculated using the formula.
Here, n = 15 (the total number of guests) and k = 4 (the number of prizes to be awarded).
So, the number of ways to award the prizes is:
C(15, 4) = 15! / (4! (15 - 4)!)
= 15! / (4! 11!)
= 15 x 14 x 13 x 12 / (4 x 3 x 2 x 1)
= 1365.
Therefore, there are 1365 different ways to award the 4 door prizes to 4 guests from a group of 15 guests.
Learn more about permutation here:
brainly.com/question/1216161
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What is 32 divided by the opposite of 4
Answer: -8
Since we are dividing the OPPOSITE of 4 then we are dividing 32÷-4
When multiplying or dividing a POSITIVE to a NEGATIVE you get a NEGATIVE
P/N=N
N/N=P
P*P=P
P=Positive
N=Negative
Divide
32/-4=-8
So your answer is -8
When 32 is divided by opposite of 4 the obtained result is - 8.
What is additive inverse ?Additive inverse of a number is such a number when the original number and it's additive inverse is added we get zero.
4 + ( - 4 ) = 0.So the additive inverse of 4 is - 4.
According to the given question we have to obtain the result when 32 is divided by opposite of 4.
Here opposite of 4 means additive inverse of 4 which is -4.
∴ 32/-4
= - 8.
learn more about additive inverse here :
https://brainly.com/question/13715269
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In the diagram, XY bisects ZWXZ.
Z
Y
2
w
(5x + 3)
(7X - 70°
Х
x=
type your answer...
Answer:
x = 5
Step-by-step explanation:
Angle Bisector Theorem: When a ray bisects an angle, we get 2 congruent smaller angles
Step 1: Set equation equal to each other (Angle Bisector Theorem)
5x + 3 = 7x - 7
Step 2: Subtract 5x on both sides
3 = 2x - 7
Step 3: Isolate x term (Add 7 to both sides)
10 = 2x
Step 4: Isolate x (Divide both sides by 2)
x = 5
20 POINTS! You are planning to use a ceramic tile design in your new bathroom. The tiles are equilateral triangles. You decide to arrange the tiles in a hexagonal shape as shown. If the side of each tile measures 9 centimeters, what will be the exact area of each hexagonal shape?
Answer:
210.33 cm^2
Step-by-step explanation:
We know that 6 equilateral triangles makes one hexagon.
Also, an equilateral triangle has all its sides equal.
If the tile of each side of the triangular tile measure 9 cm, then the height of the triangular tiles can be gotten using Pythagoras's Theorem.
The triangle formed by each tile can be split along its height, into two right angle triangles with base (adjacent) 4.5 cm and slant side (hypotenuse) of 9 cm. The height (opposite) is calculated as,
From Pythagoras's theorem,
[tex]hyp^{2} = adj^{2} + opp^{2}[/tex]
substituting, we have
[tex]9^{2} = 4.5^{2} + opp^{2}[/tex]
81 = 20.25 + [tex]opp^{2}[/tex]
[tex]opp^{2}[/tex] = 81 - 20.25 = 60.75
opp = [tex]\sqrt{60.75}[/tex] = 7.79 cm this is the height of the right angle triangle, and also the height of the equilateral triangular tiles.
The area of a triangle = [tex]\frac{1}{2} bh[/tex]
where b is the base = 9 cm
h is the height = 7.79 cm
substituting, we have
area = [tex]\frac{1}{2}[/tex] x 9 x 7.79 = 35.055 cm^2
Area of the hexagon that will be formed = 6 x area of the triangular tiles
==> 6 x 35.055 cm^2 = 210.33 cm^2
Suppose 50 percent of the customers at Pizza Palooza order a square pizza, 70 percent order a soft drink, and 35 percent order both a square pizza and a soft drink.
Required:
Is ordering a soft drink independent of ordering a square pizza? Explain
Answer:
Ordering a soft drink is independent of ordering a square pizza.
Step-by-step explanation:
20% more customers order a soft drink than pizza, therefore they cannot be intertwined.
Given: P(A)=0.5 & P(B)=.7
P(A∩B) = P(A) × P(B)
= 0.5 × .7
= 0.35
P(A∪B) = P(A) + P(B) - P(A∩B)
= 0.5 + .7 - 0.35
= 0.85
P(AΔB) = P(A) + P(B) - 2P(A∩B)
= 0.5 + .7 - 2×0.35
= 0.5
P(A') = 1 - P(A)
= 1 - 0.5
= 0.5
P(B') = 1 - P(B)
= 1 - .7
= 0.3
P((A∪B)') = 1 - P(A∪B)
= 1 - 0.85
= 0.15
Yes ordering a soft drink is independent of ordering a square pizza.
We have given 50 percent of the customers at Pizza Palooza order a square pizza, 70 percent order a soft drink, and 35 percent order both a square pizza and a soft drink.
Let A: denote pizza
B: Soft drink
Then,
P(A)=0.5 and P(B)=0.7
And P(A∩B) = P(A) × P(B)
= 0.5 × 0.7
= 0.35
We know P(A∪B) = P(A) + P(B) - P(A∩B)
= 0.5 + 0.7 - 0.35
= 0.85
P(AΔB) = P(A) + P(B) - 2P(A∩B)
= 0.5 + 0.7 - 2×0.35
= 0.5
Also we know P(A') = 1 - P(A)
= 1 - 0.5
= 0.5
And P(B') = 1 - P(B)
= 1 -0.7
= 0.3
And P((A∪B)') = 1 - P(A∪B)
= 1 - 0.85
= 0.15
Learn more:https://brainly.in/question/16017018
Can someone explain to me what a “derivative” means? How do you find the derivative of f(x)=x^3+1?
This graph shows the US unemployment rate from August 2010 to November 2011.
Sample Unemployment Rate
Graph
Unemployment Rate
10%
80%
6%
Unemployment Rate
Aug 10
Jan 11
Jun 11
Nov 11
This graph suggests unemployment in the United States
O will continue to fall.
O will continue to rise.
O will remain the same.
O will only change a little.
Answer: Will continue to rise
Step-by-step explanation:
Looking at the graph one notices that after a slight dip in the unemployment rate from August 2010 to January 2011, the unemployment rate began to rise and by November 2011 was still rising.
The arrow on the graph serves to indicate the direction the unemployment rate is going and as it is pointing upwards, this means that the Unemployment rate will continue to rise.
This was down to the fact that in 2011 the US was still yet to recover from the Great Recession of 2008 - 2009.
Answer:
EDGE 2021
Step-by-step explanation:
1) 4%
2) Increase
Your investment club has only two stocks in its portfolio. $25,000 is invested in a stock with a beta of 0.8, and $40,000 is invested in a stock with a beta of 1.7. What is the portfolio's beta? Do not round intermediate calculations. Round your answer to two decimal places.
Answer:
The portfolio beta is [tex]\alpha = 1.354[/tex]
Step-by-step explanation:
From the question we are told that
The first investment is [tex]i_1 = \$ 25,000[/tex]
The first beta is [tex]k = 0.8[/tex]
The second investment is [tex]i_2 = \$ 40,000[/tex]
The second beta is [tex]w = 1.7[/tex]
Generally the portfolio beta is mathematically represented as
[tex]\alpha = \frac{ i_1 * k + i_2 * w }{ i_1 + i_2}[/tex]
substituting values
[tex]\alpha = \frac{ (25000 * 0.8) + ( 40000* 1.7 ) }{40000 + 25000}[/tex]
[tex]\alpha = 1.354[/tex]
Next, the students at the Pearson Cooking Academy are assigned a take-home written exam to assess their knowledge of all things culinary. Historically, students scores on this exam had a N(68, 36) distribution. However, these days, there is an company called Charred Egg that offers to help students on tasks whether or not the exercises are for homework or for exams. In a cohort of 19 students, what is the probability that their average score will be at least 70?
Answer:
The probability is [tex]P( \= X \ge 70 ) = 0.07311[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 68[/tex]
The standard deviation is [tex]\sigma = \sqrt{36} = 6[/tex]
The sample size is [tex]n = 19[/tex]
Generally the standard error of the mean is mathematically represented as
[tex]\sigma_{\= x } = \frac{\sigma }{\sqrt{n} }[/tex]
=> [tex]\sigma_{\= x } = \frac{6 }{\sqrt{19} }[/tex]
=> [tex]\sigma_{\= x } = 1.3765[/tex]
Generally the probability that their average score will be at least 70 is mathematically represented as
[tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - P(\frac{ \= X - \mu }{\sigma_{\= x}} < \frac{70 - 68}{ 1.3765} )[/tex]
Generally [tex]\frac{ \= X - \mu }{\sigma_{\= x}} = z(The \ z-score \ of \ \= X )[/tex]
So
[tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - P(Z <1.453 )[/tex]
From the z-table
[tex]P(Z <1.453 ) = 0.92689[/tex]
=> [tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - 0.92689[/tex]
=> [tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 0.07311[/tex]
=> [tex]P( \= X \ge 70 ) = 0.07311[/tex]
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:
[tex]Area=\frac{1}{2} (B\,+\,b)\,h[/tex]
Step-by-step explanation:
The grassy area is that of a trapezoid, so recall the formula for the area of a trapezoid:
[tex]Area=\frac{1}{2} (Base\,+\,base)\,height[/tex]
where:
Base stands for the larger base (in our case the dimension "B" in the attached image)
base stands for the shorter base parallel to the largest Base (in our case the dimension "b" in the attached image)
and
height stands for the distance between bases (in our case the dimension "h" in the attached image.
Therefore the formula for the area of the grassy section becomes:
[tex]Area=\frac{1}{2} (Base\,+\,base)\,height\\Area=\frac{1}{2} (B\,+\,b)\,h[/tex]
Answer:
1/2 (b+b) h
here is the actual picture
A cardboard box without a lid is to be made with a volume of 4 ft 3 . Find the dimensions of the box that requires the least amount of cardboard.
Answer:
2ft by 2ft by 1 ftStep-by-step explanation:
Total surface of the cardboard box is expressed as S = 2LW + 2WH + 2LH where L is the length of the box, W is the width and H is the height of the box. Since the cardboard box is without a lid, then the total surface area will be expressed as;
S = lw+2wh+2lh ... 1
Given the volume V = lwh = 4ft³ ... 2
From equation 2;
h = 4/lw
Substituting into r[equation 1;
S = lw + 2w(4/lw)+ 2l(4/lw)
S = lw+8/l+8/w
Differentiating the resulting equation with respect to w and l will give;
dS/dw = l + (-8w⁻²)
dS/dw = l - 8/w²
Similarly,
dS/dl = w + (-8l⁻²)
dS/dw = w - 8/l²
At turning point, ds/dw = 0 and ds/dl = 0
l - 8/w² = 0 and w - 8/l² = 0
l = 8/w² and w =8/l²
l = 8/(8/l² )²
l = 8/(64/I⁴)
l = 8*l⁴/64
l = l⁴/8
8l = l⁴
l³ = 8
l = ∛8
l = 2
Hence the length of the box is 2 feet
Substituting l = 2 into the function l = 8/w² to get the eidth w
2 = 8/w²
1 = 4/w²
w² = 4
w = 2 ft
width of the cardboard is 2 ft
Since Volume = lwh
4 = 2(2)h
4 = 4h
h = 1 ft
Height of the cardboard is 1 ft
The dimensions of the box that requires the least amount of cardboard is 2ft by 2ft by 1 ft
find the value of x? please help
Answer:
49
Step-by-step explanation:
With these types of problems, you have to subtract the outer and inner values and then divide by 2. So, (125-27)/2 = 49. Hope this helps!
The sum of the reciprocals of two consecutive even integers is 3/4
Find the two integers.
[tex] \Large{ \underline{ \underline{ \bf{ \orange{Solution:}}}}}[/tex]
Let one of those even numbers be x, Then other even number would be x + 2.
According to question,
⇛ Their reciprocal add upto 3/4
So, we can write it as,
⇛ 1/x + 1/x + 2 = 3/4
⇛ x + 2 + x / x(x + 2) = 3/4
⇛ 2x + 2 / x² + 2x = 3/4
Cross multiplying,
⇛ 3(x² + 2x) = 4(2x + 2)
⇛ 3x² + 6x = 8x + 8
⇛ 3x² - 2x - 8 = 0
⇛ 3x² - 6x + 4x - 8 = 0
⇛ 3x(x - 2) + 4(x - 2) = 0
⇛ (3x + 4)(x - 2) = 0
Then, x = -4/3 or 2
☃️ It can't be -4/3 because it is fraction and negative number. So, x = 2
Then, x + 2 = 4
✤ So, The even numbers are 2 and 4.
━━━━━━━━━━━━━━━━━━━━
Use the number line below, where RS = 6y + 2, ST = 3y + 7, and RT = 14y - 11.
a. What is the value of y?
b. Find RS, ST, and RT.
Answer:
a) y = 4
b) RS = 26, ST = 19, RT = 45
Step-by-step explanation:
From the line given, the following vector equation is true, RS + ST = RT since R, S and T lies in the same straight line.
Given RS = 6y + 2, ST = 3y + 7, and RT = 14y - 11
On substituting this values into the equation above we will have;
6y+2+(3y+7) = 14y-11
6y+2+3y+7 = 14y-11
Collect the like terms
6y+3y-14y = -11-7-2
9y-14y = -20
-5y = -20
y = 20/5
y = 4
Since RS = 6y + 2
RS = 6(4)+2
RS = 24+2
RS = 26
ST = 3y + 7
ST = 3(4)+7
ST = 12+7
ST = 19
Also, RT = 14y - 11
RT = 14(4)-11
RT = 56-11
RT = 45
Aiko and Kendra arrive at the Texas
State Fair with $60. What is the total
number of rides they can go on if
they each pay the entrance fee of
$17 and rides cost $3 each?
Answer:
They can go on 14 rides the maximum.
Step-by-step explanation:
First, you have to set up the equation. Basically, Aiko and Kendra only carry $60 with them. They cannot go over that limit. Furthermore, the entrance free is $17. Each ride is $3.
(x = the amount of rides)
17 + 3x ≤ 60
17 represents the entrance fee which only has to be paid one time. 3x represents the cost of each ride (x equals to the amount of rides).
Now you solve.
Isolate the variable, which is 3x.
3x ≤ 60 - 17
3x ≤ 43
Now, divide 43 by 3 to find the value of x.
x ≤ 43 ÷ 3
x ≤ 14.3333333333
They can go on a max of 14 rides. Anymore, and they will go over budget. Normally, with problems like this one, if you have a decimal, you should round down unless your instructor says otherwise.
After all, who would you be able to go on a third of a ride? It isn't possible, so generally, they just have you round down.
Joe drove 315 miles on 15 gallons of gas. What is his mileage in miles/gallon?
miles/gallon
Answer:
21 miles/gallon
Step-by-step explanation:
To find his mileage in miles/gallon, divide the number of miles by the number of gallons.
315/15
= 21
= 21 miles/gallon
Answer:
21 miles / gallon
Step-by-step explanation:
Take the miles and divide by the gallons
315 miles / 15 gallons
21 miles / gallon
Find the probability that when a couple has four children, at least one of them is a boy. (Assume that boys and girls are equally likely.)
Answer:
The probability that at least, one of the four children the couple has is a boy is 0.8.
Step-by-step explanation:
Given that boys and girls are equally likely, we want to find the probability of having at least, one boy, from four children..
Note that it is possible to have the following for 4 children:
1. 4 boys, 0 girls
2. 3 boys, 1 girl
3. 2 boys, 2 girls
4. 1 boy, 3 girls
5. 0 boys, 4 girls.
To have at least, one boy, out of the 5 options, only 4 is possible.
1. 4 boys, 0 girls.........YES
2. 3 boys, 1 girl ...........YES
3. 2 boys, 2 girls.........YES
4. 1 boy, 3 girls.............YES
5. 0 boys, 4 girls..........NO
The probability is therefore,
(Probability of event = 4) ÷ (Total possible outcome = 5)
P = 4/5 = 0.8
Commute times in the U.S. are heavily skewed to the right. We select a random sample of 45 people from the 2000 U.S. Census who reported a non-zero commute time. In this sample the mean commute time is 25.2 minutes with a standard deviation of 19.1 minutes. Required:a. Can we conclude from this data that the mean commute time in the U.S. is less than half an hour?b. Conduct a hypothesis test at the 5% level of significance. c. What is the p-value for this hypothesis test?
Answer:
The mean commute time in the U.S. is less than half an hour.
Step-by-step explanation:
In this case we need to test whether the mean commute time in the U.S. is less than half an hour.
The information provided is:
[tex]n=45\\\bar x=25.5\\s=19.1\\\alpha =0.05[/tex]
(a)
The hypothesis for the test can be defined as follows:
H₀: The mean commute time in the U.S. is not less than half an hour, i.e. μ ≥ 30.
Hₐ: The mean commute time in the U.S. is less than half an hour, i.e. μ < 30.
(b)
As the population standard deviation is not known we will use a t-test for single mean.
Compute the test statistic value as follows:
[tex]t=\frac{\bar x-\mu}{s/\sqrt{n}}=\frac{25.2-30}{19.1/\sqrt{45}}=-1.58[/tex]
Thus, the test statistic value is -1.58.
(c)
Compute the p-value of the test as follows:
[tex]p-value=P(t_{(n-1)}<-1.58)=P(t_{(45-1)}<-1.58)=0.061[/tex]
*Use a t-table.
The p-value of the test is 0.061.
Decision rule:
If the p-value of the test is less than the significance level then the null hypothesis will be rejected and vice-versa.
p-value = 0.061> α = 0.05
The null hypothesis will not be rejected at 5% level of significance.
Thus, concluding that the mean commute time in the U.S. is less than half an hour.
12-(3-9) 3*3 help please
Step-by-step explanation:
42 is your answer according to bodmas
(1 point) Consider the function f(x)=2x3−9x2−60x+1 on the interval [−4,9]. Find the average or mean slope of the function on this interval. Average slope: By the Mean Value Theorem, we know there exists at least one value c in the open interval (−4,9) such that f′(c) is equal to this mean slope. List all values c that work. If there are none, enter none . Values of c:
Answer: c = 4.97 and c = -1.97
Step-by-step explanation: Mean Value Theorem states if a function f(x) is continuous on interval [a,b] and differentiable on (a,b), there is at least one value c in the interval (a<c<b) such that:
[tex]f'(c) = \frac{f(b)-f(a)}{b-a}[/tex]
So, for the function f(x) = [tex]2x^{3}-9x^{2}-60x+1[/tex] on interval [-4,9]
[tex]f'(x) = 6x^{2}-18x-60[/tex]
f(-4) = [tex]2.(-4)^{3}-9.(-4)^{2}-60.(-4)+1[/tex]
f(-4) = 113
f(9) = [tex]2.(9)^{3}-9.(9)^{2}-60.(9)+1[/tex]
f(9) = 100
Calculating average:
[tex]6c^{2}-18c-60 = \frac{100-113}{9-(-4)}[/tex]
[tex]6c^{2}-18c-60 = -1[/tex]
[tex]6c^{2}-18c-59 = 0[/tex]
Resolving through Bhaskara:
c = [tex]\frac{18+\sqrt{1740} }{12}[/tex]
c = [tex]\frac{18+41.71 }{12}[/tex] = 4.97
c = [tex]\frac{18-41.71 }{12}[/tex] = -1.97
Both values of c exist inside the interval [-4,9], so both values are mean slope: c = 4.97 and c = -1.97
(x+1)(x−1)(x−5)=0 HELP
Answer:
x³ - 5x² - x + 5
Step-by-step explanation:
(x+1)(x-1)(x-5) = 0
fisrt step:
(x+1)(x-1) = x*x + x*-1 + 1*x + 1*-1 = x² - x + x - 1 = x² - 1
then:
(x+1)(x-1)(x-5) = (x²-1)(x-5)
(x²-1)(x-5) = x²*x + x²*-5 -1*x -1*-5 = x³ - 5x² - x + 5
idk how to put the picture but can someone just tell me the points where the two dots go plz will give good rate nd say thx plz answer fast
Graph -8x-y=8
Answer:
(-1,0) and (0,-8)
Step-by-step explanation:
Hey there!
Well first we’ll graph -8x - y = 8,
Look at the image below
By lookig at the image below we can tell the 2 points are at,
(-1,0) and (0,-8)
Hope this helps :)
83=4k-7(1+7k) How to solve
Answer:
k = -2
Step-by-step explanation:
83=4k-7(1+7k)
Distribute
83=4k-7-49k
Combine like terms
83 = -45k -7
Add 7 to each side
83+7 = -45k-7+7
90 = -45k
Divide each side by -45
90/-45 = -45k/-45
-2 = k
Answer:
k = -2Step-by-step explanation:
Step 1: Use 7 to open the bracket :
-7(1+7k)=-7-49k
Step 2: Collect like terms
Step 3 : Divide both sides of the equation by -45
[tex]83=4k-7(1+7k) \\ \\83 = 4k-7-49k\\\\ 83+7=4k-49k\\\\90 = -45k\\\\\frac{90}{-45} = \frac{-45k}{-45} \\\\k = -2[/tex]
A lottery exists where balls numbered 1 to "20" are placed in an urn. To win, you must match the balls chosen in the correct order. How many possible outcomes are there for this game?
Answer: 1860480
Step-by-step explanation:
Initially, there are 20 balls where 5 must be chosen in order.
The number of possible outcomes may be calculated using the concept of permutations.
The formula for permutations is:
nPr =n!/(n−r)!
where n represents the number of items and r represents the number of items to be selected.
The number of ways of selecting 5 balls in order out of 20 is:
20P5 = 20!/15!
= 1860480
To conclude, there are 1860480 possible outcomes.