Answer:
0.7994 = 79.94% probability that the proportion of persons with myopia will differ from the population proportion by less than 3%.
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.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Suppose 42% of the population has myopia.
This means that [tex]p = 0.42[/tex]
Random sample of size 442 is selected
This means that [tex]n = 442[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.42[/tex]
[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.42*0.58}{442}} = 0.0235[/tex]
What is the probability that the proportion of persons with myopia will differ from the population proportion by less than 3%?
Proportion between 0.42 + 0.03 = 0.45 and 0.42 - 0.03 = 0.39, which is the p-value of Z when X = 0.45 subtracted by the p-value of Z when X = 0.39.
X = 0.45
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.45 - 0.42}{0.0235}[/tex]
[tex]Z = 1.28[/tex]
[tex]Z = 1.28[/tex] has a p-value of 0.8997
X = 0.39
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.39 - 0.42}{0.0235}[/tex]
[tex]Z = -1.28[/tex]
[tex]Z = -1.28[/tex] has a p-value of 0.1003
0.8997 - 0.1003 = 0.7994
0.7994 = 79.94% probability that the proportion of persons with myopia will differ from the population proportion by less than 3%.
The equation for the pH of a substance is pH = -log[H], where Ht iS the concentration of hydrogen ions. A basic
solution has a pH of 11.2. An acidic solution has a pH of 2.4. What is the approximate difference in the concentration
of hydrogen ions between the two solutions?
Answer:
The difference in the H⁺ concentration between the two solutions is approximately equal to the H⁺ concentration of the acidic solution.
Step-by-step explanation:
The pH is given by:
[tex] pH = -log[H^{+}] [/tex]
Where:
[tex] [H^{+}][/tex]: is the concentration of hydrogen ions.
For the basic solution (pH = 11.2), the concentration of H⁺ is given by:
[tex] [H^{+}]_{b} = 10^{-pH} = 10^{-11.2} = 6.31 \cdot 10^{-12} [/tex]
And, for the acidic solution (pH = 2.4) we have:
[tex] [H^{+}]_{a} = 10^{-pH} = 10^{-2.4} = 3.98 \cdot 10^{-3} [/tex]
Hence, the difference in the concentration of H⁺ between the two solutions is:
[tex] \Delta H^{+} = [H^{+}]_{a} - [H^{+}]_{b} = 3.98 \cdot 10^{-3} - 6.31\cdot 10^{-12} = 3.98 \cdot 10^{-3} [/tex]
Therefore, the difference in the H⁺ concentration between the two solutions is approximately equal to the H⁺ concentration of the acidic solution.
I hope it helps you!
Answer:
B. 4.0 x [tex]10^{-3}[/tex]
Step-by-step explanation:
EDG2021
Which of the following values cannot be probabilities? 3/5, 2, 0, 1, −0.45, 1.44, 0.05, 5/3 Select all the values that cannot be probabilities.
Given:
The numbers are [tex]\dfrac{3}{5},2,0,1,-0.45, 1.44[/tex].
To find:
All the values that cannot be probabilities.
Solution:
We know that,
[tex]\text{Probability}=\dfrac{\text{Favorable outcomes}}{\text{Total outcomes}}[/tex]
The minimum value of favorable outcomes is 0 and the maximum value is equal to the total outcomes. So, the value of probability lies between 0 and 1, inclusive. It other words, the probability lies in the interval [0,1].
[tex]0\leq \text{Probability}\leq 1[/tex]
From the given values only [tex]\dfrac{3}{5}, 0, 1[/tex] lie in the interval [0,1]. So, these values can be probabilities.
The values [tex]2,-0.45, 1.44[/tex] does not lie in the interval [0,1]. So, these values cannot be probabilities.
Therefore, the correct values are [tex]2,-0.45, 1.44[/tex].
What is the slope of the line that passes through (17, −13) and (17, 8)?
(also can you try to explain ive been having trouble with these types of question)
Answer:
Slope is undefined. Line parallel to y-axis.
Step-by-step explanation:
By Analytic Geometry, we can determine the slope of a line by knowing two distinct lines and using the definition of secant line:
[tex]m = \frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex] (1)
Where:
[tex](x_{1}, y_{1})[/tex] - Coordinates of the initial point.
[tex](x_{2}, y_{2})[/tex] - Coordinates of the final point.
[tex]m[/tex] - Slope.
If we know that [tex](x_{1}, y_{1}) = (17, -13)[/tex] and [tex](x_{2}, y_{2}) = (17, 8)[/tex], then the slope of the line is:
[tex]m = \frac{8-(-13)}{17-17}[/tex]
[tex]m = \frac{21}{0}[/tex]
The slope is undefined, which means that line is parallel to y-axis.
Use sigma notation to represent the sum of the first seven terms of the following sequence: −4, −6, −8, …
Answer:
[tex]\sum_{n = 1}^{7} -2 -2n[/tex]
Step-by-step explanation:
Arithmetic sequence:
In an arithmetic sequence, the difference of consecutive terms is always the same, called common difference.
The nth term of a sequence is given by:
[tex]a_{n} = a_1 + (n-1)d[/tex]
In which [tex]a_1[/tex] is the first term and d is the common difference.
Sigma notation to represent the sum of the first seven terms
Sum going from the index starting at 1 and finishing at 7, that is:
[tex]\sum_{n = 1}^{7} f(n)[/tex]
Now we have to fund the function, which is given by an arithmetic sequence.
−4, −6, −8,
First term -4, common difference - 6 - (-4) = -6 + 4 = -2, so [tex]a_1 = -4, d = -2[/tex]
Then
[tex]f(n) = a_{n} = a_1 + (n-1)d[/tex]
[tex]f(n) = -4 + (n-1)(-2)[/tex]
[tex]f(n) = -4 - 2n + 2 = -2 - 2n[/tex]
Sigma notation:
Replacing f(n)
[tex]\sum_{n = 1}^{7} -2 -2n[/tex]
1.A multiple choice exam has five possible answers per question. Only one of those five answers is the correct answer. A student, who did not prepare for the test,answers the exam randomly and in order,starting from the first question. a.What is the probability that the first question he answered correctly is the second question
Answer:
Step-by-step explanation:
P(answers correctly)=1/5
P(answers incorrectly)=1-1/5=4/5
P( answers correctly second question)=4/5 ×1/5=4/25
What is the midpoint of AB?
Answer:
point G
Step-by-step explanation:
There's 14 marks between point A and B(counting point B). 14/2=7, the 7th mark is point G.
At an intersection, the red light times are normally distributed with a mean time of 3 minutes and a standard deviation of 0.25 minutes. Approximately what percent of red lights last between 2.5 and 3.5 minutes? (2 points)
Answer:
95.4%
Step-by-step explanation:
Z(low)=-2 0.022750132
Z(upper)=2 0.977249868
Lauren flips a coin, spins the spinner, and rolls a standard number cube. Find the probability that the coin will
show heads, the spinner will land on green, and the cube will show an even number.
Lauren will get 2/25 because the coin only lands on heads or tail
Which of these figures has rotational symmetry?
Hello!
The answer is a.
Good luck! :)
The time for a professor to grade a student’s homework in statistics is normally distributed with a mean of 13.3 minutes and a standard deviation of 2.0 minutes. What is the probability that randomly selected homework will require less than 17 minutes to grade?
Answer:
0.96784
Step-by-step explanation:
17-13.3/2
=1.85
p(x<1.85)
=0.96784
The probability that randomly selected homework will require less than 17 minutes to grade is 0.9678.
Mean [tex]\mu[/tex]=13.3 minutes
Standard deviation[tex]\sigma[/tex]=2 minutes
What is a z-score?The value of the z-score tells you how many standard deviations you are away from the mean.
So, the z-score of the above data
[tex]z=\frac{x-\mu}{\sigma}[/tex]
[tex]z=\frac{17-13.3}{2}[/tex]
[tex]z=1.85[/tex]
From the standard normal table, the p-value corresponding to z=1.85
Or, p(x<1.85)=0.9678 or 96.78%
Hence, the probability that randomly selected homework will require less than 17 minutes to grade is 0.9678.
To get more about the z-score visit:
https://brainly.com/question/25638875
help asap! Might be easy for some of you
Answer:
51
Step-by-step explanation:
(-3)^4-5(5)+6(5)÷(-3)(2)
81-25+30÷-6
81-25-5
81-30
51
(Remember order of operations-PEMDAS)
Find the Taylor series for f(x) centered at the given value of a. (Assume that f has a power series expansion. Do not show that Rn(x)→0 . f(x)=lnx, a=
Answer:
Here we just want to find the Taylor series for f(x) = ln(x), centered at the value of a (which we do not know).
Remember that the general Taylor expansion is:
[tex]f(x) = f(a) + f'(a)*(x - a) + \frac{1}{2!}*f''(a)(x -a)^2 + ...[/tex]
for our function we have:
f'(x) = 1/x
f''(x) = -1/x^2
f'''(x) = (1/2)*(1/x^3)
this is enough, now just let's write the series:
[tex]f(x) = ln(a) + \frac{1}{a} *(x - a) - \frac{1}{2!} *\frac{1}{a^2} *(x - a)^2 + \frac{1}{3!} *\frac{1}{2*a^3} *(x - a)^3 + ....[/tex]
This is the Taylor series to 3rd degree, you just need to change the value of a for the required value.
1^2 +2^2+••••+n^2=1/6n(n+1)(2n+1)
using maths induction
Hello,
[tex]if\ n=1\ then\ 1^2=1\ and\ \dfrac{1}{6}*1*2*3=1:\ true\ for\ n=1\\[/tex]
We suppose the property true for n:
1²+2²+...+n²=n(n+1)(2n+1) / 6
and we are going to demonstrate that the property is true for n+1:
1²+2²+..+(n+1)²=(n+1)*(n+2)*(2n+3)/6
[tex]1^2+2^2+...+n^2+(n+1)^2\\\\=n*(n+1)*(2n+1)/6+(n+1)^2\\\\=(n+1)/6*[n(2n+1)+6n+6]\\\\=(n+1)/6*(2n^2+7n+6)\\\\=(n+1)(n+2)(2n+3)/6\\[/tex]
Your sample is normally distributed with a mean age of 36. The standard deviation in this sample is 4 years. You would expect:
Kindly find complete question attached below
Answer:
Kindly check explanation
Step-by-step explanation:
Given a normal distribution with ;
Mean = 36
Standard deviation = 4
According to the empirical rule :
68% of the distribution is within 1 standard deviation of the mean ;
That is ; mean ± 1(standard deviation)
68% of subjects :
36 ± 1(4) :
36 - 4 or 36 + 4
Between 32 and 40
2.)
95% of the distribution is within 2 standard deviations of the mean ;
That is ; mean ± 2(standard deviation)
95% of subjects :
36 ± 2(4) :
36 - 8 or 36 + 8
Between 28 and 44
3.)
99% is about 3 standard deviations of the mean :
That is ; mean ± 3(standard deviation)
99% of subjects :
36 ± 3(4) :
36 - 12 or 36 + 12
Between 24 and 48
The population of retired citizens in Minneapolis is 86700. If the population increases at a rate of 8.9% each year. What will the population of retirees be in 7 years? Write an exponential growth model for the future population P(x) where r is in years: P(x) = What will the population be in 7 years? (Round to nearest person)
Answer:
157,476 people
Step-by-step explanation:
the formula :
P(x) = 86700. (1+ 0.089)^r
for r = 7
=> P(x) = 86700 × (1+ 0.089)^7
= 86700 × (1.089)^7
= 86700 × 1.8163
= 157,476 people
What is the depth of water in a tank with 300,000 gallons of water at 70F when the pressure gauge at the bottom of the tank reads 23 psig?
Answer:
53.08 ft
Step-by-step explanation:
The pressure at the bottom of the tank, P = ρgh where ρ = density of water = 1000 kg/m³, g = acceleration due to gravity = 9.8 m/s² and h = depth of water in tank.
Since the pressure at the bottom of the tank, P = ρgh, making h subject of the formula, we have
h = P/ρg
Since P = 23 psig = 23 × 1 psig = 23 × 6894.76 Pa = 158579.48 Pa
Substituting the values of the other variables into h, we have
h = P/ρg
h = 158579.48 Pa/(1000 kg/m³ × 9.8 m/s²)
h = 158579.48 Pa/(9800 kg/m²s²)
h = 16.18 m
h = 16.18 × 1 m
h = 16.18 × 3.28 ft
h = 53.08 ft
Given that Z1 = 1 + i and Z2 = 3 - 4i, find z1z2
Answer:
7-i
Step-by-step explanation:
It is asking for the product of the given complex numbers.
Z1Z2 means Z1 times Z2
(1+i)(3-4i)
You can do the whole foil thing here since we are multiplying a pair of binomials. But all you are doing when you do that is multiplying every term in the first ( ) to every term in the second ( ).
1(3)+1(-4i)+i(3)+i(-4i)
Simplify each term. That is, perform the multiplication in each term:
3-4i+3i-4i^2
Combine like terms and also replace i^2 with (-1):
3-1i-4(-1)
Multiplication identity property used:
3-i+4
Combine like terms:
7-i
Help me with this question, please!!
Answer:
4yz^2
Step-by-step Explanation:
How many students rank themselves as introverts? Demonstrate your work.
Answer:
36 introverts
Step-by-step explanation:
Total number of adults in the survey = 120
Ratio of introverts to extroverts = 3:7
Number of introverts = ratio number of introverts / ratio total × 120
Ratio number of introverts = 3
Ratio total = 3 + 7 = 10
Number of introverts = 3/10 × 120
= 36
Please HELP!
How many pairs (A, B) are there where A and B are subsets of {1, 2, 3, 4, 5, 6, 7, 8} and A ∩ B has exactly two elements?
Answer:
There are 256 pairs in all.
please show me step by step how to simplify this equation
Answer:
1-x^2/x^3 - 1 = 1/x
Step-by-step explanation:
First rewrite x^3 as x^2 * x cancel x^2 in both numerator and denominator.
Write below
1 - 1/x - 1
Subtract
1 - 1 = 0
now simplify
1 -1 /x - 1 = 1/x
1/x = Answer
Can you Understand
What are the coordinates of point p?
I need help answering this question.
Answer:
6x
Step-by-step explanation:
If x is the length of one side, and each side is the same length, you will multiply it by 6 times (there are 6 sides in a hexagon).
So, you will add it up 6 times, but you can say 6x for short.
Find the width of a photograph whose length is 24 inches and whose proportions
are the same as a photograph that is 3 inches wide by 4 inches long.
A photograph having length of 24 inches which is proportionate to another photograph having dimensions 3 × 4 inches, has width of 18 inches.
What is proportion?
In general, the term "proportion" refers to a part, share, or amount that is compared to a whole. According to the definition of proportion, two ratios are in proportion when they are equal.
Let the width of the photograph be x inches.
The length of the photograph is 24 inches.
A similar proportion photograph has width as 3 inches.
A similar proportion photograph has length as 4 inches.
The equation to find the width of photograph is -
x / 24 = 3 / 4
Simplify the equation -
x = (24 × 3) / 4
x = 72 / 4
x = 18
Therefore, the width value is 18 inches.
To learn more about proportion from the given link
https://brainly.com/question/19994681
#SPJ1
The head of maintenance at XYZ Rent-A-Car believes that the mean number of miles between services is 4959 miles, with a standard deviation of 448 miles. If he is correct, what is the probability that the mean of a sample of 43 cars would differ from the population mean by less than 111 miles
Answer:
0.8948 = 89.48% probability that the mean of a sample of 43 cars would differ from the population mean by less than 111 miles
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.
The mean number of miles between services is 4959 miles, with a standard deviation of 448 miles
This means that [tex]\mu = 4959, \sigma = 448[/tex]
Sample of 43:
This means that [tex]n = 43, s = \frac{448}{\sqrt{43}}[/tex]
What is the probability that the mean of a sample of 43 cars would differ from the population mean by less than 111 miles?
p-value of Z when X = 4959 + 111 = 5070 subtracted by the p-value of Z when X = 4959 - 111 = 4848, that is, probability the sample mean is between these two values.
X = 5070
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{5070 - 4959}{\frac{448}{\sqrt{43}}}[/tex]
[tex]Z = 1.62[/tex]
[tex]Z = 1.62[/tex] has a p-value of 0.9474
X = 4848
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{4848 - 4959}{\frac{448}{\sqrt{43}}}[/tex]
[tex]Z = -1.62[/tex]
[tex]Z = -1.62[/tex] has a p-value of 0.0526
0.9474 - 0.0526 = 0.8948
0.8948 = 89.48% probability that the mean of a sample of 43 cars would differ from the population mean by less than 111 miles
Solve using the elimination method
x + 5y = 26
- X+ 7y = 22
Answer:
[tex]x=6\\y=4[/tex]
Step-by-step explanation:
Elimination method:
[tex]x+5y=26[/tex]
[tex]-x+7y=22[/tex]
Add these equations to eliminate x:
[tex]12y=48[/tex]
Then solve [tex]12y=48[/tex] for y:
[tex]12y=48[/tex]
[tex]y=48/12[/tex]
[tex]y=4[/tex]
Write down an original equation:
[tex]x+5y=26[/tex]
Substitute 4 for y in [tex]x+5y=26[/tex]:
[tex]x+5(4)=26[/tex]
[tex]x+20=26[/tex]
[tex]x=26-20[/tex]
[tex]x=6[/tex]
{ [tex]x=6[/tex] and [tex]y=4[/tex] } ⇒ [tex](6,4)[/tex]
hope this helps...
Answer:
x = 6, y = 4
Step-by-step explanation:
x + 5y = 26
- x + 7y = 22
_________
0 + 12y = 48
12y = 48
y = 48 / 12
y = 4
Substitute y = 4 in eq. x + 5y = 26,
x + 5 ( 4 ) = 26
x + 20 = 26
x = 26 - 20
x = 6
find the slope and y-intercept of line 3x +y -9=0
Answer:
x-intercept(s):(3,0)
y-intercept(s):(0,9)
Step-by-step explanation:
I need help with this question.
Answer:
Step-by-step explanation:
f(x-2) means that x is happening sooner or a shift to the left and
+4 means that the whole function moves up 4.
The 1st choice looks good
Convert 0.53 hectograms to centigrams.
53 centigrams
0.000053 centigrams
530 centigrams
5,3000 centigrams
Answer:
As for metric prefixes, "hecto" means hundred and "centi" means hundredth.
So, converting .53 hectograms to centigrams requires multiplying it by 10,000.
So, .53 hectograms * 10,000 equals 5,300 centigrams.
Source http://www.1728.org/convprfx.htm
Step-by-step explanation:
Please answer & number. Thank you! <33
Answer:
2）=2
4）=3
5）=5
8）=-1
Step-by-step explanation:
just divide the number by the number with variable
