Answer:
a) By the Central Limit Theorem, it has an approximately normal shape, with mean(center) 0.9 and standard deviation(spread) 0.035.
b) Average numbers of children between 0.83 and 0.97 are reasonably likely in the sample.
c) 0.0021 = 0.21% probability that the average number of children per family in the sample will be 0.8 or less
d) 0.9958 = 99.58% probability that the average number of children per family in the sample will be between 0.8 and 1.0
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Mean 0.9 and standard deviation 1.1.
This means that [tex]\mu = 0.9, \sigma = 1.1[/tex]
Suppose a television network selects a random sample of 1000 families in the United States for a survey on TV viewing habits.
This means that [tex]n = 1000, s = \frac{1.1}{\sqrt{1000}} = 0.035[/tex]
a. Describe (as shape, center and spread) the sampling distribution of the possible values of the average number of children per family.
By the Central Limit Theorem, it has an approximately normal shape, with mean(center) 0.9 and standard deviation(spread) 0.035.
b. What average numbers of children are reasonably likely in the sample?
By the Empirical Rule, 95% of the sample is within 2 standard deviations of the mean, so:
0.9 - 2*0.035 = 0.83
0.9 + 2*0.035 = 0.97
Average numbers of children between 0.83 and 0.97 are reasonably likely in the sample.
c. What is the probability that the average number of children per family in the sample will be 0.8 or less?
This is the p-value of Z when X = 0.8. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.8 - 0.9}{0.035}[/tex]
[tex]Z = -2.86[/tex]
[tex]Z = -2.86[/tex] has a p-value of 0.0021
0.0021 = 0.21% probability that the average number of children per family in the sample will be 0.8 or less.
d. What is the probability that the average number of children per family in the sample will be between 0.8 and 1.0?
p-value of Z when X = 1 subtracted by the p-value of Z when X = 0.8.
X = 1
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{1 - 0.9}{0.035}[/tex]
[tex]Z = 2.86[/tex]
[tex]Z = 2.86[/tex] has a p-value of 0.9979
X = 0.8
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.8 - 0.9}{0.035}[/tex]
[tex]Z = -2.86[/tex]
[tex]Z = -2.86[/tex] has a p-value of 0.0021
0.9979 - 0.0021 = 0.9958
0.9958 = 99.58% probability that the average number of children per family in the sample will be between 0.8 and 1.0
two trains leave the station at the same time, one traveling due east, the other due west. After 46 minutes, they are 140 miles apart. if one trains speed is 20 mph more than the other trains, what are the speeds of the two trains?
Answer:
Train A speed = x + 20
Train B = x
We know the 46 minutes is 23/30 of an hour.
Use D = rt
Take it from it, hope its helped, have a great day!
Help please and thanks !!
Answer:
4th option
Step-by-step explanation:
tanZ = [tex]\frac{opposite}{adjacent }[/tex] = [tex]\frac{XY}{ZY}[/tex]
I need help asap and a step by step!!!!!!!!!!!!!!!!!!!!
Answer:
Step-by-step explanation:
1. subtract 3.5-3.5 and 12.5-3.5
2.You should 4t=9
3. Divide 4 ÷ 4 and 9 ÷ 4
4. You should have t = 2.25
Answer:
t = 2.25
Step-by-step explanation:
4t + 3.5 = 12.5Step 1 :- Divide both side by 3.5.
4t + 3.5 - 3.5 = 12.5 - 3.54t = 9Step 2 :- Divide each side by 4.
4t / 4 = 9 / 4t = 2.25f(x) = 2x + 9
f^-1(x)= ??
Step-by-step explanation:
Given
f(x) = 2x + 9
f^-1 (x) = ?
Let
y = f(x)
y = 2x + 9
Interchanging the roles of x and y we get
x = 2y + 9
2y = x - 9
y = ( x - 9) / 2
Therefore
⏩f^-1(x) = (x-9)/2
Hope it will help :)
Jo invest 5000 at a rate of 2% per year compound interest.calculate the value of her investment at the end of 3years.
Answer:
If you need further explanation, comment on this
Help please!!!!!!!???!!!!
Answer:
The equation is
y=0.5x+2
Speedy Oil provides a single-server automobile oil change and lubrication service. Customers provide an arrival rate of 2.5 cars per hour. The service rate is 5 cars per hour. Assume that arrivals follow a Poisson probability distribution and that service times follow an exponential probability distribution. What is the average number of cars in the system
Answer:
the average number of car(s) in the system is 1
Step-by-step explanation:
Given the data in the question;
Arrival rate; λ = 2.5 cars per hour
Service time; μ = 5 cars per hour
Since Arrivals follows Poisson probability distribution and service times follows exponential probability distribution.
Lq = λ² / [ μ( μ - λ ) ]
we substitute
Lq = (2.5)² / [ 5( 5 - 2.5 ) ]
Lq = 6.25 / [ 5 × 2.5 ]
Lq = 6.25 / 12.5
Lq = 0.5
Now, to get the average number of cars in the system, we say;
L = Lq + ( λ / μ )
we substitute
L = 0.5 + ( 2.5 / 5 )
L = 0.5 + 0.5
L = 1
Therefore, the average number of car(s) in the system is 1
Consider the quadratic function F(x)=-x^2-x+20
The line of symmetry has the equation ?
Answer:
[tex]x = - \frac{1}{2} [/tex]
Step-by-step explanation:
[tex]x = \frac{ - b}{2a} = \frac{1}{ - 2} [/tex]
Does anyone know the awnser please
Answer:
please which level is this
and also is it core maths or elective math
Matthew earns extra money by doing odd jobs for his neighbors. He charges a flat fee of $20 plus $7 per hour for each job. If he earned $90 for a job he did last week, how many hours did he work?
Answer:
10 hours
Step-by-step explanation:
ok so we know he is getting payed $20 + $7 every hour so what i would do is keep the multiply the 7 till you get 70 so thats 7x10=70 and 70+20=90 so he worked for 10 hours last week :) i hope this helps, i tried my best to explain it
Find the expected value of the winnings
from a game that has the following
payout probability distribution:
Payout($) 2 46 8 10
Probability 0.5 0.2 0.15 0.1 0.05
Expected Value = [?]
The expected payout is
2 × 0.5 + 4 × 0.2 + 6 × 0.15 + 8 × 0.1 + 10 × 0.05
= 1 + 0.8 + 0.9 + 0.8 + 0.5
= 4
The expected value of the winnings from this game is $3.90.
What is probability?It is the chance of an event to occur from a total number of outcomes.
The formula for probability is given as:
Probability = Number of required events / Total number of outcomes.
Example:
The probability of getting a head in tossing a coin.
P(H) = 1/2
We have,
To find the expected value of the winnings, we multiply each possible payout by its probability and then sum these products.
So,
Expected Value = (2 x 0.5) + (4 x 0.2) + (6 x 0.15) + (8 x 0.1) + (10 x 0.05)
Expected Value = 1 + 0.8 + 0.9 + 0.8 + 0.5
Expected Value = 3.9
Therefore,
The expected value of the winnings from this game is $3.90.
Learn more about probability here:
https://brainly.com/question/14099682
#SPJ7
Geometry PLS HELP due soon
Answer:
(3) [tex]x = 7.5[/tex] and [tex]y = 51[/tex]
(4) [tex]x = 6[/tex]
Step-by-step explanation:
Question 3
Required
Solve for x and y
We have:
[tex]16x - 18 + 10x +3 = 180[/tex] --- angle on a straight line
Collect like terms
[tex]16x + 10x = 180 + 18 - 3[/tex]
[tex]26x = 195[/tex]
Solve for x
[tex]x = 195/26[/tex]
[tex]x = 7.5[/tex]
Also:
[tex]16x - 18 = 2y[/tex] ---- opposite angles
So, we have:
[tex]16 * 7.5 - 18 = 2y[/tex]
[tex]120 - 18 = 2y[/tex]
[tex]102 = 2y[/tex]
Divide by 2
[tex]51 = y[/tex]
[tex]y = 51[/tex]
Question 4:
Required
Solve for x
We have:
[tex]11x - 2 + 5x - 4 = 90[/tex] ---- angle at right-angled
Collect like terms
[tex]11x + 5x = 90 +2 + 4[/tex]
[tex]16x = 96[/tex]
Divide by 16
[tex]x = 6[/tex]
Verify which of the following are identities.
Which graph represents the function?
Answer:
D
Step-by-step explanation:
I have attached the explanation above. hopefully this will help
(7+3i)-(3-9i)complex numbers
Answer:
C
Step-by-step explanation:
For this, you want to treat i like any other variable, and combine like terms. However you need to keep in mind that there is a negative sign before the second set of parentheses. This means everything inside it should have a negative before it. So we can write it like this:
(7 + 3i) - (3 - 9i)
7 + 3i -3 +9i
4 + 12i
Hope that helps!
pls help will give brainliest, 5* and thanks
trolls will get reports
Answer:
1.
M = 20 degrees
n =28.74
p = 20.12
2.
B = 73.65 degrees
C = 43.35 degrees
c = 30.05
3.
F = 21 degrees
G = 124 degrees
g = 23.13
Step-by-step explanation:
the law of sines is for a triangle ABC
a/sin(A) = b/sin(B) = c/sin(C)
1.
the sum of all angles in a triangle is always 180 degrees.
so, M = 180 - 125 - 35 = 20 degrees
m/sin(M) = n/sin(N)
12/sin(20) = n/sin(125)
sin(125) = sin(180-125) = sin(55)
n = 12×sin(55)/sin(20) = 28.74
p/sin(P) = m/sin(M)
p/sin(35) = m/sin(20)
p = m×sin(35)/sin(20) = 12×sin(35)/sin(20) = 20.12
2.
a/sin(A) = b/sin(B)
39/sin(63) = 42/sin(B)
sin(B) = 42×sin(63)/39 = 14×sin(63)/13
B = 73.65 degrees
therefore,
C = 180 - 63 - 73.65 = 43.35 degrees
c/sin(43.35) = 39/sin(63)
c = 39×sin(43.35)/sin(63) = 30.05
3.
e/sin(E) = f/sin(F)
16/sin(35) = 10/sin(F)
sin(F) = 10×sin(35)/16 = 5×sin(35)/8
F = 21 degrees
therefore,
G = 180 - 35 - 21 = 124 degrees
g/sin(124) = 16/sin(35)
sin(124) = sin(180-124) = sin(56)
g/sin(56) = 16/sin(35)
g = 16×sin(56)/sin(35) = 23.13
Evaluate x2 + 4x + 1 when x = -3
Answer:
[tex]-2[/tex]
Step-by-step explanation:
Just substitute -3 for all instances of x.
[tex](-3)^{2} + 4(-3) + 1\\\\[/tex]
[tex]9 - 12 + 1[/tex]
[tex]-2[/tex]
The following data was obtained from 32 people aged 25-29 who were asked how many hours of TV they watched per week.
4,2,8,9,4,5,10,11,7,8,3,4,10,3,8,5,1,7,0,4,3,2,2,1,1,0,2,3,5,2,1,1.
Group the data in intervals and record the frequency of each interval as well as the cumulative frequency and relative frequency. Make a table showing this information.
Graph the data using frequency histogram.
Graph the data using a cumulative frequency chart.
Tell whether ADEF and AGHI can be proven
congruent.
A.No, ADEF and AGHI aren't congruent
because they don't share a side.
B.Yes, ADEF and AGHI can be proven
congruent by HL.
C.No, there isn't enough information
because the triangles aren't right
triangles.
D.Yes, ADEF and AGHI can be proven
congruent by SSS.
Answer:
A. No, ADEF, and AGHI aren't congruent because they don't share a side.
----------------------------
hope it helps...
have a great day!!
Help ! ASAP please and thank you !!
that alot of work shhheeshhh
A regression was run to determine whether there is a relationship between hours of tv watched per day(x) and number of sit-ups a person can do (y). The results of the regression are given below. Use this to predict the number of sit-ups a person who watches 11 hours of tv can do
Y=ax+b
A=-1.341
B=32.234
R=-0.896
Answer:
17
Step-by-step explanation:
Given the regression model :
Y=ax+b
x = Hours of TV watched per day
y= number of sit-ups a person can do
A=-1.341
B=32.234
Y = - 1.341x + 32.234
Predict Y, when x = 11
Y = - 1.341(11) + 32.234
Y = −14.751 + 32.234
Y = 17.483
Hence, the person Cann do approximately 17 sit-ups
Based on a poll, among adults who regret getting tattoos, 16% say that they were too young when they got their tattoos. Assume that eight adults who regret getting tattoos are randomly selected, and find the indicated probability.
Answer:
The problem is incomplete, but it is solved using a binomial distribution with [tex]n = 8[/tex] and [tex]p = 0.16[/tex]
Step-by-step explanation:
For each adult who regret getting tattoos, there are only two possible outcomes. Either they say that they were too young, or they do not say this. The answer of an adult is independent of other adults, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
16% say that they were too young when they got their tattoos.
This means that [tex]p = 0.16[/tex]
Eight adults who regret getting tattoos are randomly selected
This means that [tex]n = 8[/tex]
Find the indicated probability.
The binomial distribution is used, with [tex]p = 0.16, n = 8[/tex], that is:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = x) = C_{8,x}.(0.16)^{x}.(0.84)^{8-x}[/tex]
Categorize the following logical fallacy.
John Bardeen's work at the Advanced Institute for Physics has progressed so slowly that even his colleagues call him a plodder. Hence, it is prudent at present not to take seriously his current theory relating how strings constitute the smallest of subatomic particles.
a. Circular reasoning
b. False dilemma
c. Appeal to consequence
d. Ad hominem
e. Correlation implies causation
Answer:
d. Ad hominem
Step-by-step explanation:
A fallacy can be defined as a mistaken or false belief that are based on illogical arguments or reasoning.
However, a lot of people might actually think it to be true but it isn't. There are various types of fallacy, these include;
I. Black or white.
II. Non sequitur.
III. Appeal to moderation.
IV. Bandwagon.
V. Appeal to authority.
VI. Straw man.
VII. Oversimplification or hasty generalization.
VIII. Appeal to ignorance.
IX. Appeal to pity.
X. Ad hominem.
Ad hominem can be defined as a type of fallacy in which the motive, character, or some other aspect of a person is attacked rather than his or her position.
This ultimately implies that, Ad hominem is typically based on prejudices, emotions, or feelings rather than appealing to reason, intellect or substance.
In this scenario, John Bardeen's research work at the Advanced Institute for Physics has progressed so slowly that even his colleagues call him a plodder. As a result, the speaker concluded that it's prudent at present not to take seriously his current theory on how strings constitute the smallest of subatomic particles. Thus, the logical fallacy described above is an ad hominem because John's slowness in his research work is bone of contention for the speaker rather than analyzing and concentrating on his theory about strings.
Use implicit differentiation to find an equation of the tangent line to the curve at the given point. x2 + 6xy + 12y2 = 28, (2, 1) (ellipse)
Answer:
The equation of the tangent line is [tex]y = -\frac{5}{18}\cdot x +\frac{14}{9}[/tex].
Step-by-step explanation:
Firstly, we obtain the equation for the slope of the tangent line by implicit differentiation:
[tex]2\cdot x + 6\cdot y + 6\cdot x \cdot y' + 24\cdot y \cdot y' = 0[/tex]
[tex]2\cdot (x + 3\cdot y) + 6\cdot (x + 4\cdot y) \cdot y' = 0[/tex]
[tex]6\cdot (x + 4\cdot y) \cdot y' = -2\cdot (x+3\cdot y)[/tex]
[tex]y' = -\frac{1}{3}\cdot \left(\frac{x + 3\cdot y}{x + 4\cdot y} \right)[/tex] (1)
If we know that [tex](x,y) = (2, 1)[/tex], then the slope of the tangent line is:
[tex]y' = -\frac{1}{3}\cdot \left(\frac{2+3\cdot 1}{2 + 4\cdot 1} \right)[/tex]
[tex]y' =-\frac{5}{18}[/tex]
By definition of tangent line, we determine the intercept of the line ([tex]b[/tex]):
[tex]y = m\cdot x + b[/tex]
[tex]b = y - m\cdot x[/tex] (2)
If we know that [tex](x,y) = (2,1)[/tex] and [tex]m = -\frac{5}{18}[/tex], then the intercept of the tangent line is:
[tex]b = 1 - \left(-\frac{5}{18} \right)\cdot (2)[/tex]
[tex]b = \frac{14}{9}[/tex]
The equation of the tangent line is [tex]y = -\frac{5}{18}\cdot x +\frac{14}{9}[/tex].
Which operation must you use to find the water temperature after the submarine’s final dive? Which word or words in the problem signify this operation?
Answer:
the temperature drops 2 degrees F
Step-by-step explanation:
Answer:
The problem states that the temperature drops 2 degrees F. The word drops signifies that I should subtract 2 1/5 degrees F from 63 1/4 F.
Step-by-step explanation:
Solve the simultaneous equations
2x+3y20
2x+5=10
Answer:
[tex]x=\frac{5}{2} \\y=5[/tex]
( 5/2, 2 )
Step-by-step explanation:
Solve by substitution method:
[tex]2x+5=10\\\2x+3y=20[/tex]
Solve [tex]2x+5=10[/tex] for [tex]x[/tex]:
[tex]2x+5=10[/tex]
[tex]2x=10-5[/tex]
[tex]2x=5[/tex]
[tex]x=5/2[/tex]
Substitute [tex]5/2[/tex] for [tex]x[/tex] in [tex]2x+3y=20[/tex]:
[tex]2x+3y=20[/tex]
[tex]2(\frac{5}{2} )+3y=20[/tex]
[tex]3y+5=20[/tex]
[tex]3y=20-5[/tex]
[tex]3y=15[/tex]
[tex]y=15/3[/tex]
[tex]y=5[/tex]
∴ [tex]x=\frac{5}{2}[/tex] and [tex]y=5[/tex]
hope this helps....
can anyone help me and explain
Answer:
cf
=41
5 f-46
Step-by-step explanation:
thiis is the answer
Answer:
To find the inverse, switch the y(F(C)) and the x(C) variables.
So this function:
[tex]y=\frac{9}{5}x+32 \\[/tex]
Will become this function:
[tex]x=\frac{9}{5}y+32 \\[/tex]
You will then solve for y:
[tex]x=\frac{9}{5}y+32 \\x-32=\frac{9}{5}y\\5(x-32)=5(\frac{9}{5}y)\\5x-160=9y\\y=\frac{5x-160}{9}\\y=\frac{5x}{9}-\frac{160}{9}[/tex]
Substitute in the variables of this problem:
[tex]C(F)=\frac{5C}{9}-\frac{160}{9}[/tex]
please i meed help!!! im stuck and cant concentrate
Answer:
A. 8h=m
Step-by-step explanation:
$8* h= total money m earned.
An unconditional acceptance into a graduate program at a university will be given to students whose GMAT score plus 100 times the undergraduate grade point average is at least 1075. Robbin's GMAT score was 800. What must her grade point average be in order to be unconditionally accepted into the program?
Robbin's grade point average must be at least ___ in order to be unconditionally accepted into the program.
Answer:
Robbin's grade point average must be at least 2.75 in order to be unconditionally accepted into the program.
Step-by-step explanation:
An unconditional acceptance into a graduate program at a university will be given to students whose GMAT score plus 100 times the undergraduate grade point average is at least 1075
Considering the GMAT score x, and the GPA y, this situation is modeled by the following inequality:
[tex]x + 100y \geq 1075[/tex]
Robbin's GMAT score was 800.
This means that [tex]x = 800[/tex], and thus:
[tex]x + 100y \geq 1075[/tex]
[tex]800 + 100y \geq 1075[/tex]
[tex]100y \geq 275[/tex]
What must her grade point average be in order to be unconditionally accepted into the program?
Solving the above inequality for y:
[tex]100y \geq 275[/tex]
[tex]y \geq \frac{275}{100}[/tex]
[tex]y \geq 2.75[/tex]
Thus:
Robbin's grade point average must be at least 2.75 in order to be unconditionally accepted into the program.
You are designing an experiment using human subjects. The study will include 30 participants. Of these, 16 will be placed in the experimental group and the remaining 14 will be placed in the control group. In how many ways can you assign participants to the two groups?
Answer:
The participants can be assigned in 224 different ways.
Step-by-step explanation:
Given that you are designing an experiment using human subjects, and the study will include 30 participants, of which 16 will be placed in the experimental group and the remaining 14 will be placed in the control group, to determine in how many ways can you assign participants to the two groups the following calculation must be performed:
16 x 14 = X
224 = X
Therefore, the participants can be assigned in 224 different ways.
