Answer:
0.9029 = 90.29% probability that the mean of the sample would differ from the population mean by less than 3.8 points if 76 exams are sampled
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]
The mean points obtained in an aptitude examination is 167 points with a standard deviation of 20 points
This means that [tex]\mu = 167, \sigma = 20[/tex]
Sample of 76:
This means that [tex]n = 76, s = \frac{20}{\sqrt{76}}[/tex]
What is the probability that the mean of the sample would differ from the population mean by less than 3.8 points?
P-value of Z when X = 167 + 3.8 = 170.8 subtracted by the p-value of Z when X = 167 - 3.8 = 163.2. So
X = 170.8
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{170.8 - 167}{\frac{20}{\sqrt{76}}}[/tex]
[tex]Z = 1.66[/tex]
[tex]Z = 1.66[/tex] has a p-value of 0.9515
X = 163.2
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{163.2 - 167}{\frac{20}{\sqrt{76}}}[/tex]
[tex]Z = -1.66[/tex]
[tex]Z = -1.66[/tex] has a p-value of 0.0485
0.9514 - 0.0485 = 0.9029
0.9029 = 90.29% probability that the mean of the sample would differ from the population mean by less than 3.8 points if 76 exams are sampled
Suppose that you are headed toward a plateau 37 meters high. If the angle of elevation to the top of the plateau is , how far are you from the base of the plateau?
Answer:
21.36 meters
Step-by-step explanation:
Given
[tex]h = 37m[/tex]
[tex]\theta = 60^o[/tex]
Required
The distance from the base (b)
The question illustrates right-angled triangle (see attachment)
To solve for (b), we make use of tangent formula
[tex]\tan(60)=\frac{h}{b}[/tex]
Make b the subject
[tex]b =\frac{h}{\tan(60)}[/tex]
So:
[tex]b =\frac{37}{\tan(60)}[/tex]
[tex]b =\frac{37}{1.7321}[/tex]
[tex]b =21.36[/tex]
What is the value of b?
Answer:
?
Step-by-step explanation:
Solve this equation log3X + log3(x-6) = log3 7
Hello!
log₃(x) + log₃(x - 6) = log₃(7) <=>
<=> log₃(x * (x - 6)) = log₃(7) <=>
<=> log₃(x² - 6x) = log₃(7) <=>
<=> x² - 6x = 7 <=>
<=> x² - 6x - 7 = 0 <=>
<=> x² + x - 7x - 7 = 0 <=>
<=> x * (x + 1) - 7 * (x + 1) = 0 <=>
<=> (x + 1) * (x - 7) = 0 <=>
<=> x + 1 = 0 and x - 7 = 0 <=>
<=> x = -1 and x = 7, x ∈ { 6; +∞ } <=>
<=> x = 7
Good luck! :)
Calculate the difference and enter it below.
-5 - (-10)
Answer: Simply the expression = 5
Step-by-step explanation:
Simplify = 5
Step-by-step explanation:
-5-(-10) = -5+10 = 5
Therefore the answer of your question is 5.
Mark me as the brainliest answer.
Determine the value of the missing letters in the sum of numbers
below:
ab1
+ ba
abb
49x
Answer:
a=2, b=3,x=6
Step-by-step explanation:
We are given that
We have to find the value of the missing letters in the sum of numbers.
From given sum
1+a+b=x ....(1)
b+b+b=9 .....(2)
a+a=4 ......(3)
From equation (2) we get
[tex]3b=9[/tex]
[tex]\implies b=3[/tex]
From equation (3) we get
[tex]2a=4[/tex]
[tex]a=4/2[/tex]
[tex]a=2[/tex]
Now, substitute the values in equation (1) we get
[tex]1+2+3=x[/tex]
[tex]x=6[/tex]
Therefore,
231+32+233=496
find the equation of the line shown
Answer:
y=1/2x+1/2
Step-by-step explanation:
In order to find the slope, you can use rise/run, in this case, the slope is 1/2 and the y-intercept is at (0, 0.5)
For all positive integers n, let *n* equal the greatest prime number that is a divisor of n. What does *10*/*12* equal?
9514 1404 393
Answer:
5/3
Step-by-step explanation:
The prime factorizations are ...
10 = 2·5
12 = 2·2·3
Then *10* = 5 and *12* = 3, so *10*/*12* = 5/3.
Can someone help me with me? Thanks!
Answer:
(0.38, 4.79)
Step-by-step explanation:
Find how long it takes a person to drive 90 miles on a highway if she merges onto a highway at 3p.m. and drives nonstop with her cruise control set on 40 mph.
How long does is take a person to drive 90 miles?
(type an integer or a decimal)
Answer:
2.25 or 2 hours 15 mins
Step-by-step explanation:
90/40 = 2.25
CANE SOMEONE HELP ME ON GEOMETRY
[tex]option(c) \: cylinder[/tex]
Step-by-step explanation:
You can see that in the figure, this is rectangle. Here, ABCD is rotated around the vertical line through A and D. So, you will get Cylinder shape as you rotate it.
Find the area of the following figure with the indicated dimensions.use pi.
Answer:
The answer is "47.5354".
Step-by-step explanation:
In the given graph it is a half-circle and a triangle.
So, the diameter of the circle is 6.2 so the radius is 3.1
[tex]\text{Area of a circle}= \pi r^2\\\\\text{Area of a triangle}= \frac{1}{2} b h\\\\[/tex]
Calculating the total area of the shape:
[tex]= \pi r^2+\frac{1}{2} \times b\times h\\\\ = 3.14 \times 3.1^2+\frac{1}{2} \times 6.2 \times 5.6\\\\ = 3.14 \times 3.1^2+\frac{1}{2} \times 6.2 \times 5.6\\\\=3.14 \times 9.61+\frac{1}{2} \times 34.72\\\\=3.14 \times 9.61+\frac{1}{2} \times 34.72\\\\= 30.1754+17.36\\\\=47.5354\\\\[/tex]
Candice is preparing for her final exam in Statistics. She knows she needs an 74 out of 100 to earn an A overall in the course. Her instructor provided the following information to the students. On the final, 200 students have taken it with a mean score of 68 and a standard deviation of 4. Assume the distribution of scores is bell-shaped. Calculate to see if a score of 74 is within one standard deviation of the mean.
a) Yes, 74 is the upper limit of one standard deviation from the mean.
b) Yes, the upper level of one standard deviation is 72.
c) Yes, 74 is greater than the 64, one standard deviation below the mean.
d) No, 74 is greater than the mean of 68.
Answer:
Hence the correct option is option b) Yes, the upper level of one standard deviation is 72.
A score of 74 is not within one standard deviation of the mean.
Step-by-step explanation:
Here the given details are,
Mean = 68
SD = 4
Distribution is normal.
Z-score for x = 74 is given as below:
[tex]Z = (X - mean)/SD\\Z = (74 - 68)/4\\Z = 1.5[/tex]
So, the score of 74 is 1.5 standard deviations from the mean.
[tex]Mean + 1\timesSD = 68 + 1\times4 = 72Mean - 1\timesSD = 68 - 1\times4 = 64[/tex]
Therefore the score is not lies between 64 and 72.
Yes, the upper level of one standard deviation is 72.
Expand 5(2x-1) please I need it for homework.
10x-5
Answer:
5(2x-1)
5*2x 5*-1
10x-5
Hey there!
5(2x - 1)
= 5(2x) + 5(-1)
= 10x - 5
Therefore, your answer should be: 5x - 5
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)
Floataway Tours has $420,000 that can be use to purchase new rental boats for hire during the summer. The boats can be purchased from two different manufacturers. Floataway Tours would like to purchase at least 50 boats and would like to purchase the same number from Sleekboat as from Racer to maintain goodwill. At the same time,Floataway Tours wishes to have a total seating capacity of at least 200.
Required:
Formulate this problem as a linear program.
Answer and explanation:
A linear problem is an equation based on known and unknown variables that follow a linear path, usually without exponents and look like this:
y=mx+b. To formulate the linear constraints of the problem above, we look at the unknown variables and known variables and define and equation using this.
From the problem, assume x and y are the prices of the different boat brands:
50x+50y=420000
Assume a and b are number of x brand boats and y brand boats supplied thus:
a+b>=200
rewrite 1/6 and 2/11 so they have a common denominator then use <, =, or > to order
Answer:
1/6 < 2/11
Step-by-step explanation:
1/6 = 2/12
2/11 >2/12
So that means 1/6 < 2/11
Answer: 1/6 < 2/11
This is the same as saying 11/66 < 12/66
===========================================================
Explanation:
1/6 is the same as 11/66 when multiplying top and bottom by 11.
2/11 is the same as 12/66 when multiplying top and bottom by 6.
The 6 and 11 multipliers are from the original denominators (just swapped).
We can see that 11/66 is smaller than 12/66, simply because 11 < 12, so that means 1/6 is smaller than 2/11
-----------------
Here's one way you could list out the steps
11 < 12
11/66 < 12/66
1/6 < 2/11
------------------
Here's another way to list out the steps. First assume that 1/6 and 2/11 are equal. Cross multiplication then leads to
1/6 = 2/11
1*11 = 6*2
11 = 12
Which is false. But we can fix this by replacing every equal sign with a less than sign
1/6 < 2/11
1*11 < 6*2
11 < 12
---------------------
Yet another way to see which is smaller is to use your calculator or long division to find the decimal form of each value
1/6 = 0.1667 approximately
2/11 = 0.1818 approximately
We see that 0.1667 is smaller than 0.1818, which must mean 1/6 is smaller than 2/11.
the focus of a parabola is (-5,-1) and the directrix is y= -3.
what is an equation of the parabola? (one of the answered above)
Answer:
Step-by-step explanation:
-2
What is this expression in simplified form?
Answer:
16 √(3)
and then the decimal form if needed is: 27.7128129211
Step-by-step explanation:
Determine which statements about the relationship are true. Choose two options. g is the dependent variable. u is the dependent variable. g is the independent variable. u is the independent variable. The two variables cannot be labeled as independent or dependent without a table of values.
Answer:
1) g is the dependent variable.(A)
2) u is the independent variable.(D)
Step-by-step explanation:
please help i guess on a
Answer:
A = (2, 2)
B = (3, -1)
C = (-1, 0)
Step-by-step explanation:
To translate a point, you have to translate each individual point. At the bottom it shows <-2,3>, therefore you have to translate x 2 units to the left (because it's negative meaning the number is going away from 0, and 3 units to the right because 3 is a positive number.)
First Point A:
x: 4 - 2 = 2; y: -1 + 3 = 2
Second Point B:
x: 5 - 2 = 3; y: -4 + 3 = -1
Lastly, Point C:
x: 1 - 2 = -1, y: -3 + 3 = 0
I hope this helps!
hello guys i need help
Step-by-step explanation:
90*8.25=742 rounds to 675 because its the closest. 85-95=10 divided by 2=5+85=90. 9-7.5=1.5 divided by 2=0.75+7.5=8.25. thats how i got those numbers. THE ANSWER IS C
A study of the pay of corporate chief executive officers (CEOs) examined the increase in cash compensation of the CEOs of 104 companies, adjusted for inflation, in a recent year. The mean increase in real compensation was x¯=6.9%, and the standard deviation of the increases was s=55%. Is this good evidence that the mean real compensation μ of all CEOs increased that year? The hypotheses are
Answer:
The p-value of the test is 0.1017, which is greater than the standard significance level of 0.05, which means that this is not good evidence that the mean real compensation μ of all CEOs increased that year.
Step-by-step explanation:
At the null hypothesis, we test if there was no increase, that is, the mean is 0, so:
[tex]H_0: \mu = 0[/tex]
At the alternative hypothesis, we test if there was an increase, that is, the mean is greater than 0, so:
[tex]H_1: \mu > 0[/tex]
The test statistic is:
[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, s is the standard deviation and n is the size of the sample.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
104 companies, adjusted for inflation, in a recent year. The mean increase in real compensation was x¯=6.9%, and the standard deviation of the increases was s=55%.
This means that [tex]n = 104, X = 6.9, s = 55[/tex]
Value of the test-statistic:
[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]
[tex]t = \frac{6.9 - 0}{\frac{55}{\sqrt{104}}}[/tex]
[tex]t = 1.28[/tex]
P-value of the test:
The p-value of the test is a right-tailed test(test if the mean is greater than a value), with 104 - 1 = 103 df and t = 1.28.
Using a t-distribution calculator, this p-value is of 0.1017.
The p-value of the test is 0.1017, which is greater than the standard significance level of 0.05, which means that this is not good evidence that the mean real compensation μ of all CEOs increased that year.
6. Convert 3−i into polar form and hence evaluate
[tex] {(3 - i)}^{7} [/tex]
9514 1404 393
Answer:
≈ 1000√10∠-129.04464° = -1992 -2456i
Step-by-step explanation:
3 -i = √(3³+(-1)²)∠arctan(-1/3) ≈ √10∠-18.4349°
Then (3-i)^7 = 10^(7/2)∠(7×-18.4349°) = 1000√10∠-129.04464°
= 1000√10(cos(-129.04464°) +i·sin(-129.04464°))
= -1992 -2456i
HELP HELP HELP MATH I WILL GIVE U EXTRA POINTS⚠️⚠️⚠️⚠️⚠️
Find four consecutive integers with the sum of 2021
Answer:
503.75, 504.75, 505.75, 506.75
Step-by-step explanation:
x+(x+1)+(x+2)+(x+3)=2021
4x+6=2021
4x=2015
x=503.75
so it would be
503.75+504.75+505.75+506.75= 2021
If 19,200 cm2 of material is available to make a box with a square base and an open top, find the largest possible volume of the box.
Step-by-step explanation:
√19200cm²
=138.56cm
then the highest possible volume
=(138.56)³
=2660195.926cm³
The largest possible volume of the box is; V = 25600 cm³
Let us denote the following of the square box;
Length = x
Width = y
height = h
Formula for volume of a box is;
V = length * width * height
Thus; V = xyh
but we are dealing with a square box and as such, the base sides are all equal and so; x = y. Thus;
V = x²h
The box has an open top and as such, the surface are of the box is;
S = x² + 4xh
We are given S = 19200 cm². Thus;
19200 = x² + 4xh
h = (19200 - x²)/4x
Put (19200 - x²)/4x for h in volume equation to get;
V = x²(19200 - x²)/4x
V = 4800x - 0.25x³
To get largest possible volume, it will be dimensions when dV/dx = 0. Thus;
dV/dx = 4800 - 0.75x²
At dV/dx = 0, we have;
4800 - 0.75x² = 0
0.75x² = 4800
x² = 4800/0.75
x² = 6400
x = √6400
x = 80 cm
From h = (19200 - x²)/4x;
h = (19200 - 80²)/(4 × 80)
h = (19200 - 6400)/3200
h = 4 cm
Largest possible volume = 80² × 4
Largest possible volume = 25600 cm³
Read more at; https://brainly.com/question/19053087
If f(x) = 3X + 10x and g(x) = 4x - 2, find (f+g)(x).
O A. 17x - 2
O B. 3* + 6x + 2
O C. 3* - 6x + 2
D. 3X + 14x-2
help!!!
One of the factor of x² +3x+2 is x+1 then the other factor is …..
Hi there!
[tex]\large\boxed{(x + 2)}[/tex]
x² + 3x + 2
We know that x + 1 is a factor, so:
We must find another number that adds up to 3 when added to 1 and multiplies into 2 with 1. We get:
x + 2
(x + 1)(x + 2)
help pls I need it badly
9514 1404 393
Answer:
22
Step-by-step explanation:
For calculators without a cube root key, you can use the 1/3 power. The attached shows the quotient to be about 22.
please help me i begging.
Answer:
The two equivalent expressions are 6(x − y) and 6x − 6y.
Step-by-step explanation:
Dora drove 80 km in 40 minutes then 120 km in 1 hour and then the final 200km took him 1 hour 20 minutes. what is his average speed for the whole journey
9514 1404 393
Answer:
133 1/3 km/hour
Step-by-step explanation:
Average speed is computed as ...
average speed = (total distance)/(total time)
= (80 km +120 km +200 km)/(2/3 + 1 + 1 1/3 hour) = 400 km/(3 hour)
= 133 1/3 km/hour
What is the next three-term of the geometric sequence? 60, 30, 15...?
Answer:
7.5
Step-by-step explanation:
it is feometeic progression
r=0.5