Assume that police estimate that 30% of drivers do not wear their seatbelts. They set up a safety roadblock, stopping cars
to check for seatbelt use. They stop 40 cars during the first hour.
a. Find the mean, variance, and standard deviation of the number of drivers expected not to be wearing seatbelts. Use the
fact that the mean of a geometric distribution is j = and the variance is 02 - 9
1
р
2
b. How many cars do they expect to stop before finding a driver whose seatbelt is not buckled?
=
물
...
The mean is
(Round to the nearest tenth as needed.)
The variance is
(Round to the nearest tenth as needed.)
The standard deviation is
(Do not round until the final answer. Then round to the nearest tenth as needed.)
They expect to stop cars before finding a driver whose seatbelt is not buckled.
(Round to the nearest tenth as needed.)
Answers
Using the binomial distribution, it is found that:
a)
The mean is of 12.The variance is of 8.4.The standard deviation is of 2.9.b) They expect to stop 3.3 cars before finding a driver whose seatbelt is not buckled.
For each driver, there are only two possible outcomes, either they wear their seatbelts, or they do not. The probability of a driver wearing their seatbelt is independent of any other driver, hence, the binomial distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability.
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
The variance of the binomial distribution is:
[tex]V(X) = np(1-p)[/tex]
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
In this problem:
30% of drivers do not wear their seatbelts, hence [tex]p = 0.3[/tex].They stop 40 cars during the first hour, hence [tex]n = 40[/tex].Item a:
[tex]E(X) = np = 40(0.3) = 12[/tex]
[tex]V(X) = np(1-p) = 40(0.3)(0.7) = 8.4[/tex]
[tex]\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{40(0.3)(0.7)} = 2.9[/tex]
Hence:
The mean is of 12.The variance is of 8.4.The standard deviation is of 2.9.Item b:
The number of trials until q successes of a binomial variable is modeled by a geometric distribution, with expected value given by:
[tex]E(X) = \frac{q}{p}[/tex]
In this problem, one success, hence [tex]q = 1[/tex] and:
[tex]E(X) = \frac{q}{p} = \frac{1}{0.3} = 3.3[/tex]
They expect to stop 3.3 cars before finding a driver whose seatbelt is not buckled.
To learn more about the binomial distribution, you can take a look at https://brainly.com/question/24863377
Related Questions
A jar contains black marbles and green marbles. Sixty percent of the marbles in the jar are green. A number generator simulates randomly selecting 10 marbles from the jar. The number generator is used 12 times and the number of green marbles in each trial is shown in the dot plot.
Which description is correct about the number generator being fair or not?
The number generator is not fair. The dot plot shows 80% of the marbles drawn are green.
The number generator is fair. The dot plot shows a distribution that is skewed right.
The number generator is not fair. In most of the experiments, considerably less than 60% of the selected marbles are green.
The number generator is fair. It shows that 60% of the marbles selected are green most of the time.
Answers
Answer:
The number generator is not fair. In most of the experiments, considerably less than 60% of the selected marbles are green.
Step-by-step explanation:
Run a significant number of times, a fair distribution should be a bell curve centered on the 6 for 60%
1/5 of 400 showing work
Answers
400 x 1/5 = 400/5
400/5 = 80
Which of the following graphs is described by the function given below?
y = 2x2 + 6x + 3
5
101
10
10
-20
20
- 10
10
-10
20-
101
A.
B.
C.
D.
A. Graph A
B. Graph B
O C. Graph C
D. Graph D
Answers
Answer:
Which of the following graphs is described by the function given below?
y = 2x2 + 6x + 3
-A. Graph A
The function y = 2x^2 + 6x + 3 is a quadratic function that has a vertex of (-1.5,-1.5)
How to determine the graph of the function?The equation of the function is given as:
y = 2x^2 + 6x + 3
Differentiate
y' = 4x + 6
Set to 0
4x + 6 = 0
This gives
4x = -6
Divide by 4
x = -1.5
Substitute x = -1.5 in y = 2x^2 + 6x + 3
y = 2(-1.5)^2 + 6(-1.5) + 3
Evaluate
y = -1.5
This means that the function y = 2x^2 + 6x + 3 has a vertex of (-1.5,-1.5)
See attachment for the graph of y = 2x^2 + 6x + 3
Read more about quadratic graphs at:
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Find the equation that represents the proportional relationship in this graph, for y in terms of x.
Answers
Answer:
y = 0.4 x
Step-by-step explanation:
2/7 divided by 3/4
Amanda
Answers
Answer:
2/7÷3/4=2/7×4/3=8/21
[tex] \rm \ \blue{ \overbrace{ \underbrace{ \tt \color{hotpink} \: \: \: \: \: \: \: \: \: \: answer \: \: \: \: \: \: \: \: \: }}}[/tex]
[tex]\large \color{pink} \frac{8}{21} [/tex]
Step-by-step explanation:
[tex] \huge \color{brown} \frac{2}{7} \div \frac{3}{4} [/tex]
divide by a fraction, multiply by the reciprocal of that fraction[tex] \large \color{hotpink} \frac{2}{7} \div \frac{4}{3} [/tex]
multiply the fraction[tex] \huge \color{darkblue} \frac{8}{21} [/tex]
hope it helpsplease help me and solve it
Answers
Answer:
Step-by-step explanation:
The data table represents the distance between a well-known lighthouse and a cruise ship over time. The cruise ship is travelling at uniform speed. Which equation represents the distance (y) from the lighthouse, based on the number of hours (x)? Number of Hours Distance from Lighthouse (in oceanic miles) 2 53 4 95.5 6 138 8 180.5 10 223 12 265.5 14 308 16 350.5 A. y = 42.5x + 10.5 B. y = 10.5x + 32 C. y = 21.25x + 10.5 D. y = 12.25x + 28.5 E. y = 12.5x + 10.5
Answers
Answer:
ddd
Step-by-step explanation:
solve this please this equation
Answers
Answer:
x = 80 degrees
Step-by-step explanation:
Draw a line through DG and name the intersection of that line and line AB as K.
By the same side interior angle theorem, GKC is 40 degrees.
By the sum of interior angles of triangle theorem, CGK is 180-70=110 degrees.
By supplementary angle theorem, x = 80 degrees.
Suppose ΔDEF has an exterior angle at vertex D. The measure of the exterior angle is (8x−2)º, m∠E=(3x−8)°, and m∠F=(4x+13)°. What is the measure of the exterior angle at vertex D?
A. 7°
B. 13°
C. 41°
D. 54°
Answers
The measure of the exterior angle at vertex D is: D. 54°
Recall:
The exterior angle theorem of a triangle states that the measure of an exterior angle equals the sum of the measures of two opposite interior angles of the triangle.Thus:
In ΔDEF, (8x−2)º is an exterior angle at vertex D.
m∠E = (3x−8)° (interior angle)
m∠F = (4x+13)° (interior angle)
Therefore:
(8x−2)º = (3x−8)° + (4x+13)°
Solve for x8x - 2 = 3x - 8 + 4x + 13
Combine like terms8x - 2 = 7x + 5
8x - 7x = 2 + 5
x = 7
Exterior angle at vertex D = (8x−2)º
Plug in the value of x= 8(7) - 2
= 54º (option D)
Learn more about exterior angle theorem on:
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If 3 paintings cost $30, then how much does 1 painting cost?
Answers
Answer:
10$
Step-by-step explanation:
because 10$ + 10$ + 10$ equals 30$ so one is 30$
Save You More offers a buy one/get one free item each week. Customers who purchase only one of the items must pay the regular
price. The limit is one deal per customer. Is the relation (# sale items purchased, price) a function? Why or why not?
A)
B
It is a function because the input can be either 1 or 2 items, but the output
will always be the same price.
It is not a function because the input can be either 1 or 2 items, but the
output will always be the same price.
It is a function because the input will always be the same price, but the
output can be either one or two items.
D
It is not a function because the input will always be the same price, but the
output can be either one or two items.
Answers
Answer:
It is a function because the input can be either 1 or 2 items, but the output
will always be the same price.
Step-by-step explanation:
Answer:
A. It is a function because the input can be either 1 or 2 items, but the output
will always be the same price.
Step by Step Explanation :
A function is for every single input but the output is always the same. So, let's make a scenario. If someone bought ' 1 ' then paid the marked cost and if you bought 2 then paid the marked cost BUT with " One Buy One Free. " So, it is in fact a function.
I am an odd number. Take away one letter and I become even. What number am I?
Answers
Answer:
seven
Step-by-step explanation:
Lol thxx for the points
Pls give brainliest! Also, plz sub to kgirl633 on yt.
One leg of an isosceles right triangle measures 5 inches. Rounded to the nearest tenth, what is the approximate length of the hypotenuse?
2.5 inches
5.0 inches
7.1 inches
9.8 inches
PLZ ANSWER ASAP
Answers
Answer:
C
Step-by-step explanation:
This means that there is another leg of an isosceles triangle that is also 5 inches.
a^2 + b^2 = c^2
a = 5
b = 5
c = ?
c^2 = 5^2 + 5^2 Combine
c^2 = 25 + 25
c^2 = 50 Take the square root of both sides.
sqrt(c^2) = sqrt(50^2)
c = sqrt(5 * 5 * 2) Take out 1 of two factors under the root sign.
c = 5 * sqrt(2) The 2 is left over because there is only 1 of them
sqrt(2) = 1.4142
c = 5 * 1.4142
c = 7.07 = 7.1
A furniture maker used 2/3 of a can of paint to paint some chairs. He used 1/6 of a can of paint for each chair. How many chairs did he paint?
Answers
Answer:
4 chairs
Step-by-step explanation:
Start with 2/3 can of paint: (2/3)
He used 1/6 of the can to paint each chair: (divided by 1/6)
Now use the 'keep, change, flip' method to get the expression: (2/3x6/1)
Then simplify your answer: (12/3)
Lastly simplify again: (4)
Thus, he painted 4 chairs.
7/10 of guest were over 25 what is the percentage
Answers
Espai
A house on the market was valued at $224,000. After several years, the value decreased by 9%. By how much did the house's value decrease in dollars? What
is the current value of the house?
Decrease in value:
Current house value:
Answers
Answer:
decrease in value: 20,160
current value: 203,840
Step-by-step explanation:
that is the 9% value decrease of the house
Sue has 100 dimes and quarters. If the total value of the coins is &21.40, how many of each kind of coin does she have?
Answers
Answer:
Let x be the number of dimes and y the number of quarters
x +y = 100
a dime is $0.10 and a quarter is $0.25
0.1x + 0.25y = 21.40 multiply by 100 to remove the decimals
10x + 25y = 2140, From the first equation y = 100 - x and plug it in to the second equation.
10x + 25(100 -x) = 2140
10x + 2500 - 25x =2140
2500 - 15x = 2140
360 = 15x x = 24 and y = 76
There are 24 dimes and 76 quarters
Answer:
76 Quarters = $19.00
24 Dimes = $2.40
$19.00 + $2.40 = $21.40
Step-by-step explanation:
Yaga
I need help with this solve
Answers
Answer:
the answer is 64%
Step-by-step explanation:
80/125 = 64
I need help with this answer PLEASE I’m stuck
Answers
Answer:
40% of airline A's flights were on time
Step-by-step explanation:
0.4=40% .the top row indicates that it was airline A. the left column indicates that it was on time.
Answer:
B
Step-by-step explanation:
happy holidays
What are the steps in multiplying decimals?
Answers
Answer:
Ignore the decimal points then multiply the numbers that remain. Count the number of decimal places in all of the numbers of the question combined. Place the decimal point so that there are the same number of decimal places in the answer and the question.
Step-by-step explanation:
10 miles per hour is an example of an objects what?
Answers
Step-by-step explanation:
Speed is the correct answer
How do you divide fractions? Can someone please explain step by step to get marked as brainliest!
Answers
When diving fractions, use KFC:
K eep the first fraction the same
F lip the second fraction upside down
C hange the divide sign to a multiply
After, just work it out multiplying the denominators and the numerators together getting your answer
Hope this helped you, have a good day bro cya)
K: Keep ( keep the first fraction the same)
C: Change (change your division sign to a multiplication sign)
F: Flip (flip your second faction numbers)
Ex.
Equation: 3/5 divided by 2/6
KCF: 3/5 multiplied by 6/2
Hope this helps!
Melllissa owns 4 sets of jewelry. Each set contains 2 earrings, 1 neckles, 1 bracelet, 1 ring. How many pieces of jewelry does Melissa have all together?
Answers
Answer:
The answer is to the problem is 18.
The sum of the angles of a triangle is 180 degrees. The second angle is 40 degrees more than the first
angle and the third angle is 5 times the measure of the first angle. What is the measure of the largest
angle?
Answers
Answer:
100⁰
Step-by-step explanation:
Let,
First angle = x
Second angle = x + 40
Third angle = 5x
=> x + x + 40 + 5x = 180
=> 7x + 40 = 180
=> 7x = 180 - 40
=> 7x = 140
=> x = 140/7
=> x = 20
Largest angle = 5x = 5(20) = 100⁰
[tex]\huge{\purple{\underline{\underline{\bf{\pink{ANSWER:-}}}}}}[/tex]
First angle = x Second angle = x + 40Third angle = 5x[tex]:\implies\bf{x + x + 40 + 5x = 180} \\ \\ :\implies\bf{7x + 40 = 180} \\ \\ :\implies\bf{7x = 180 - 40} \\ \\ :\implies\bf{7x = 140} \\ \\ :\implies\bf{x = \frac{140}{7} } \\ \\ :\implies\bf{x = 20}[/tex]
The largest angle above is 5x thus,
[tex]:\implies\bf{5x} \\ \\ :\implies\bf{5 \times 20} \\ \\ :\implies\bf{100^°}[/tex]
Harry is riding a train that goes 70 miles an
hour. How far will he travel is 3.5 hours?
Answers
Answer: 245 miles
Step-by-step explanation:
(70)(3.5)= 245
(70) (3.5) = 24.5
Pauline wants to sell stainless steel water bottles as a school fundraiser.
She knows that she will maximize profits, and raise $1024, if she sells
the bottles for $28 each. She also knows that she will lose $4160 if she sells the bottles for only $10 each.
Write a quadratic relation to model her profit, P, in dollars, if she sells the bottles for x dollars each.
Answers
Answer:
P = -16(x -28)² +1024
Step-by-step explanation:
The equation can be written in vertex form as ...
P = -a(x -h)² +k
where (h, k) is the vertex, and 'a' is a scale factor. We are given the vertex (h, k) = (28, 1024) and another point (x, P) = (10, -4160). Using these points, we can find the value of 'a'.
-4160 = -a(10 -28)² +1024
-5184 = -324a . . . . simplilfy
a = 5184/324 = 16 . . . . divide by the coefficient of 'a'
A suitable quadratic relation is ...
P = -16(x -28)² +1024
I need the correct answer to this problem please
Answers
Answer is ∫2x+1 = -3
Can someone help Pleasaseee
Answers
Answer:
i think it's 1.8.
Step-by-step explanation:
why? bc if u add 6/20 + 1.5 = 1.8
i think it's 1.8, im not sure, hopefully it's correct!!
Answer:
1.8
Step-by-step explanation:
you just simplify -6/20 into a decimal and you get .3 then you add it to 1.5.
2+6i/2-4i = a + bi What is the value of a? What is the value of b?
Answers
[tex]\dfrac{2+6i}{2-4i}\\\\\\=\dfrac{2(1+3i)}{2(1-2i)}\\\\\\=\dfrac{1+3i}{1-2i}\\\\\\=\dfrac{(1+3i)(1+2i)}{(1-2i)(1+2i)}\\\\\\=\dfrac{1+2i+3i+6i^2}{1-(2i)^2}\\\\\\=\dfrac{1+5i-6}{1+4}~~~~;[i^2=-1]\\\\\\=\dfrac{5i-5}{5}\\\\\\=\dfrac{5(i-1)}5\\\\=i-1\\\\=-1+i\\\\\text{It is in a form of a +bi so,}~ a = -1~ \text{and}~ b = 1[/tex]
Which graph best represents the equation x2 + (y – 1)2 = 3?
Answers
Answer:
Step-by-step explanation:
assuming the equation is x^2 + (y - 1)^2 = 3