Answer:
The probability that sample mean is less than 2 is 0.1423.
Step-by-step explanation:
Let X denote the number of accidents per week at a hazardous intersection.
It is provided that the mean and standard deviation of X are, μ = 2.2 and σ = 1.4.
(a)
According to the Central Limit Theorem if an unknown population is selected with mean μ and standard deviation σ and appropriately huge random samples (n > 30) are selected from this population with replacement, then the distribution of the sample means will be approximately normally.
Then, the mean of the sample means is given by,
[tex]\mu_{\bar x}=\mu[/tex]
And the standard deviation of the sample means is given by,
[tex]\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}[/tex]
As the sample size is not large enough, i.e. n = 9 < 30, the Central Limit Theorem cannot be applied to approximate the sampling distribution of the mean number of accidents per week at the intersection.
And since the distribution of X is not specified, the probability cannot be computed.
(b)
In this case, the sample size is large enough, i.e. n = 52 > 30, the Central Limit Theorem can be applied to approximate the sampling distribution of the mean number of accidents per week at the intersection.
Compute the probability that sample mean is less than 2 as follows:
[tex]P(\bar X<2)=P(\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}}<\frac{2-2.2}{1.4/\sqrt{56}})\\\\=P(Z<-1.07)\\\\=0.14231\\\\\approx 0.1423[/tex]
Thus, the probability that sample mean is less than 2 is 0.1423.
a line has the equation 3x-4y=1 choose the equation of a line that is parallel to the given line
Step-by-step explanation:
The equation of the given line is 3x - 4y = 1
A line parallel to the given line will have slope that is the same as this one.
The equation of a straight line is expressed as;
y = mx + c
y and x are the coordinates
m is the slope
c is the y-intercept
Now, we write the given line in the slope - intercept form;
3x - 4y = 1
-4y = -3x + 1
Divide through by -4
[tex]\frac{-4y}{-4}[/tex] = [tex]\frac{-3x}{-4}[/tex] + [tex]\frac{1}{-4}[/tex]
y = [tex]\frac{3}{4} x[/tex] - [tex]\frac{1}{4}[/tex]
The slope of this line is [tex]\frac{3}{4}[/tex]
Any line with the slope [tex]\frac{3}{4}[/tex] will be parallel to the given line.
Researchers are interested in assessing if there is an association between dietary cholesterol intake and high blood pressure. The following data was summarized:
Blood Pressure
Dietary Cholesterol High Low Total
High 159 91 250
Low 78 172 250
Total 237 263 500
Required:
a. Estimate the conditional probabilities of high and low blood pressures given the level of dietary cholesterol.
b. Compute an estimate of the odds ratio of high blood pressure for the two groups
c. Interpret the odds ratio and determine if high blood pressure is related to dietary cholesterol.
Answer:
A) Conditional probability for a high BP given that dietary cholesterol is high as well
P = 159 / 250
Conditional probability for a high BP given that dietary cholesterol is low
P = 78 / 250
Conditional probability for a low BP given that Dietary cholesterol is high
P = 91 / 250
Conditional probability for a low BP given that Dietary cholesterol is low
P = 172 / 250
B) High BP for High dietary cholesterol
= 159 / 237
High BP for low dietary cholesterol
= 78 / 237
C) The odds ratio shows that BP is directly proportional to Dietary cholesterol
Step-by-step explanation:
A) estimate the conditional probabilities of high and low blood pressures given the level of dietary cholesterol
Conditional probability for a high BP given that dietary cholesterol is high as well
P = 159 / 250
Conditional probability for a high BP given that dietary cholesterol is low
P = 78 / 250
Conditional probability for a low BP given that Dietary cholesterol is high
P = 91 / 250
Conditional probability for a low BP given that Dietary cholesterol is low
P = 172 / 250
B) Compute an estimate of the odds ratio of high blood pressure for the two groups
High BP for High dietary cholesterol
= 159 / 237
High BP for low dietary cholesterol
= 78 / 237
C) Interpret the odds ratio and determine if high blood pressure is related to dietary cholesterol.
The odds ratio shows that BP is directly proportional to Dietary cholesterol as seen in the the odds ratio that ratio between High BP and High Dietary cholesterol is higher than other odds ratios
A data set is Normally distributed with a mean of 750 and a standard deviation of 55. What is the value of a data element that has a z-value of 0.05? Give your answer to two decimal places.
752.75 IS THE CORRECT ANSWER
Answer:
752.75 is correct
ED2021
DJ has 16 movies, and Three-eighths of them are comedies. How many movies are comedies?
Answer:
16 * 3/8 = 6
6 movies are comedies
Answer: 6 movies are comedies.
Step-by-step explanation:
First expression three-eighths as a fraction then multiply it by the number of movies that DJ has in total.
three-eights = 3/8
3/8 * 16 = 48/8 = 6
What is the Magnitude of 6.8
Santiago Chile (AP)
♥plz give me brain list it would help a lot! ♥
♥ お力になれて、嬉しいです ！♥Please help!!!!
(Show work if possible)
Suppose that a population of bacteria triples every hour and starts with 700 bacteria.
(a) Find an expression for the number n of bacteria after t hours.
(b) Estimate the rate of growth of the bacteria population after 1.5 hours.
Answer:
(a) An expression for the number n of bacteria after t hours is n(t)=700*[tex]3^{t}[/tex]
(b) The rate of growth of the bacteria population after 1.5 hours is 3,996 number of bacteria per hour.
Step-by-step explanation:
An exponential function is one in which the independent variable x appears in the exponent and has a constant a as its base. Its expression is:
f(x)=aˣ
being a real positive.
When 0 <a <1, then the exponential function is a decreasing function and when a> 1, it is an increasing function.
An exponential function allows us to refer to phenomena that grow faster and faster, such as population growth.
In that case, the formula used to model the growth of a population is given by:
P(t)=P0*[tex]a^{t}[/tex]
where the function P (t) grows exponentially and represents the quantity of the population at time t; a represents the constant of growth or decrease and P0 represents the initial population at time zero.
In this case:
P0=700a=3Replacing, you get:
P(t)=700*[tex]3^{t}[/tex]
An expression for the number n of bacteria after t hours is n(t)=700*[tex]3^{t}[/tex]
The derivative of this function P (t) is:
n'(t)=700*ln(3)*[tex]3^{t}[/tex]
and reflects the growth rate of the bacteria population.
So, the rate of growth of the bacteria population after 1.5 hours is:
n(1.5)=700*ln(3)*[tex]3^{1.5}[/tex]
Solving, you get:
n(1.5)≅ 3,996
The rate of growth of the bacteria population after 1.5 hours is 3,996 number of bacteria per hour.
The following display from a TI-84 Plus calculator presents a 99% confidence interval for a proportion.Fill in the blanks: We are ________ confident that the population mean is between _______ and _______.a) 1%, 0, 0.583120b) 99%, 0, 0.583120c) 99%, 0.385631, 0.780609d) 1%, 0.385631, 0.780609
Answer:
The following display from a TI-84 Plus calculator presents a 99% confidence interval for a proportion.Fill in the blanks:
We are ____99%____ confident that the population mean is between ___0.385631____ and ___0.780609____.
c) 99%, 0.385631, 0.780609
Step-by-step explanation:
This is the only correct option, given the relevant population mean range. Option B is not correct as the population mean cannot range between 0 and 0.583120 as given by the option. Options 'a' and 'd' are not relevant to the question because they have 1% confidence level, instead of the stated 99% confidence level.
A tree that is 10 feet tall casts a 20 foot shadow. What is the length of the shadow of a nearby 30 foot tall tree
Answer:
It should be 60 feet following the pattern!
It would cast a 60 foot shadow following the pattern but depending on how far the trees are apart the 30 foot tree could also cast a 40 foot shadow:)
Ruben bought 2 large popcorn buckets and 4 small drinks for $20. Lucia bought 2 large popcorn buckets and 2 small drinks for $14. What was the cost of the large popcorn and the small drink?
Answer:
$3 for the small drinks and $4 for the large popcorn
Step-by-step explanation:
so we know that 2 popcorns and 4 small drinks give us $20 and 2 popcorns and 2 drinks gives us 14. so $6 was taken away because of two drinks and 6÷2 equals 3 therefore $3 is how much a small drink costs. after taking away another 6 from 14 because we found the costs of drinks we get $8 for two popcorns and 8÷2 is 4 so a large popcorn costs $4
Answer:
The large popcorn bucket cost $4 and the small drink cost $3.
Step-by-step explanation:
Five students came for after-school tutoring. Lin’s teacher assigned each of them the same number of problems to complete. Then he assigned each student 2 more problems. 30 problems were assigned in all. with a diagram
This is the graph of f(x). What is the value of f(2)?
A. 6
B. 5
C. 2
D. 9
Answer:
D. 9
General Formulas and Concepts:
Alg I
Reading a Cartesian PlaneIdentifying CoordinatesStep-by-step explanation:
The meaning of f(2) is x = 2. The question is asking us to find the y-value when x = 2.
According to the graph, when x = 2, y is somewhere between 8 and 10. The graph looks like it intersects right in the middle of those 2, so the y-value when x = 2 would be 9.
Therefore, f(2) = 9.
Answer:
Step-by-step explanation:
9 is the correct answer
I’ll give you a Brainly if you get this done in 3 mins -Solve each system by substitution
1) y=-3x+5
5x-4y=-3
2)y=-2
4x-3y=18
3)-7x-2y=-13
X-2y=11
4)-5x+y=-3
3x-8y=24
Answer:
1) x = 1 , y = 2
2) x=3, y=-2
3) x=3, y=-4
4) x=0, y=-3
Step-by-step explanation:
I hope this helped! please mark as brailiest
Jaden and his family are using a map to drive down to Napa Valley. On the map, the distance is given by the equation c = 1.3m, where c is the number of centimeters on the map and m is the corresponding real-world distance in miles. If they cover a distance of 18 miles, that would mean a distance of centimeters on the map.
Answer:13.84
Step-by-step explanation:
Answer:
13.84
Step-by-step explanation:
Gisele trains 7 days per week for a biathlon. She covers a total of 20 miles cycling and running each day. Gisele cycles a total of 105 miles each week, and runs a certain number of miles per week. If she cycles the same number of miles each day and runs the same number of miles each day, the equation StartFraction 1 over 7 EndFraction (105 + r) = 20 represents the situation. Which describes the solution, r, to this equation?
The solution is 5, which represents the number of miles she runs each day.
The solution is 5, which represents the number of miles she runs each week.
The solution is 35, which represents the number of miles she runs each day.
The solution is 35, which represents the number of miles she runs each week.
Answer:D :)
Step-by-step explanation:
TRUST ME
Answer:
D
Step-by-step explanation:
I just did the quiz on edge 2020-2021
I really need help
Answer:
A and D
Step-by-step explanation:
Hope this helps!
What expression can be used to add 7/10 + 13/20
I NEED HELP WITH THIS MATH PROBLEM!!
Answer:
x equal 20 Step-by-step explanation:
H equal 58 I equal 71 J equal 51 we will just simply the equation you wrote
Muller Farms uses at least 800 lb of special feed daily. The special feed is a mixture of corn and soybean meal with the following compositions:
lb per lb of feedstuff
Feedstuff Protein Fiber Cost ($/lb)
Corn .09 .02 .30
Soybean meal .60 .06 .90
The dietary requirements of the special feed are at least 30% protein and at most 5% fiber. The goal is to determine the daily minimum-cost feed mix.
(a) Formulate a linear programming (LP) problem to model the situation (minimizing cost and satisfying constraints). (Hint: let x1 be the lb of corn in the daily mix, and x2 represent the lb of soybean meal in the daily mix. Formulate objective function and constraints (3 constraints and non-negativity) according to the information given above)
(b) Set up an Excel sheet with the information of this LP problem.
(c) Use Excel Solver to compute the solution to this diet problem.
(d) Include in your report a screenshot of the Excel sheet you used to and a solution.
Answer:
470.59x₁ + 329,41x₂ = $437.65
Step-by-step explanation:
minimize: 0.30x₁ + 0.90x₂
where:
x₁ = pounds of corn
x₂ = pounds of soybean
constraints:
x₁ + x₂ ≥ 800
0.09x₁ + 0.60x₂ ≥ 0.30(800) ⇒ 0.09x₁ + 0.60x₂ ≥ 240
0.02x₁ + 0.06x₂ ≤ 0.05(800) ⇒ 0.02x₁ + 0.06x₂ ≤ 40
x₁ ≥ 0
x₂ ≥ 0
the optimal solution is: 470.59x₁ + 329,41x₂ = $437.65
What value of x makes the equation -0.2(3x – 25) = -0.1x + 7 true?
Answer:
x = -4
Step-by-step explanation:
Ok first let's put the equation.
-0.2(3x – 25) = -0.1x + 7 (first distribute the -.2 to 3x and -25)
-0.6x + 5 = -0.1x + 7 (subtract 5 on both sides)
-0.6x = -0.1x + 2 (add -0.1x on both sides)
-0.5x = 2 (divide by -0.5 on both sides)
x = -4
Hope this helps!!
Find the probability of selecting an heartt out of a
standard deck of cards.
Answer:
4/9
Step-by-step explanation:
If f(x) =(1/7)(7x)what is (3)?
?
Answer:
f(3) = 3
Step-by-step explanation:
f(x) = (1/7)(7x)
f(3) = (1/7)(7×3)
f(3) = (1/7)(21)
f(3) = 3
What is the constant of proportionality in the equation y = 5/9x
Answer: 5/9
This is assuming the equation is y = (5/9)x
Note it is in the form y = kx with k = 5/9 as the constant of proportionality.
Write the equation of the line through the points (4,5) and (12,9)
Answer:
y - 9 = 1/2 (x - 12)
Step-by-step explanation:
find slope:
9-5 = 4, 12 - 4 = 8, slope = 1/2
put in point-slope form:
y - 9 = 1/2 (x - 12)
Given: BD is perpendicular to AC, measure DBA = 7x+6. Find x
Answer:
x = 12
Step-by-step explanation:
[tex] \because BD \perp AC... (given) \\\\
\therefore m\angle DBA =90\degree... (1)\\\\
\because m\angle DBA=(7x + 6)\degree... (2)\\[/tex]
From equations (1) & (2)
[tex](7x + 6)\degree= 90\degree \\\\
7x + 6 =90\\\\
7x = 90 - 6\\\\
7x = 84\\\\
x = \frac{84}{7}\\\\
\huge \orange {\boxed {x = 12}} [/tex]
HURRY PLEASE
The quadratic function f(x) crosses the x-axis at -3 and 1.
What are the solutions of f(x) = 0?
A) -3 and -1
B) -3 and 1
C) -1 and 3
D) 1 and 3
Answer:
B
Step-by-step explanation:
The solutions to a quadratic equation is whenever the graph crosses the x-axis. The solutions are also known as the roots or zeros of the quadratic.
Our quadratic crosses the x-axis at -3 and 1. So, at those two points, f(x) is 0. Namely, we have the two points (-3, 0) and (1, 0).
So, our two solutions are -3 and 1.
Hence, our answer is B.
Answer:
I think it would be B
Step-by-step explanation:
If f(x) is 0, that means the value of x would not change at all. and since its only on the x-axis and neither numbers are used for the y-axis, the solutions would most likely be -3 and 1.
can some help me???????
Find the solution to the equations.
3x - y = -4
x + y = 0
(0,0)
(-1, 1)
(1,-1)
Answer:
(-1,1)
Step-by-step explanation:
also use elimination steps by using simultaneous
Constant rate of 2/6, 4/12, 5/15, 6/8, 10/30
Answer:
ysME
Step-by-step explanation:
A line passes through the point (2, -7) and has a slope of
21