Answer:
0.5675 = 56.75% probability that at least 22 of the 44 students selected are non-history majors.
Step-by-step explanation:
The students are chosen without replacement from the sample, which means that the hypergeometric distribution is used to solve this question. We are working also with a sample with more than 10 history majors and 10 non-history majors, which mean that the normal approximation can be used to solve this question.
Hypergeometric distribution:
The probability of x successes is given by the following formula:
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
In which:
x is the number of successes.
N is the size of the population.
n is the size of the sample.
k is the total number of desired outcomes.
Combinations formula:
[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]
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.
Approximation:
We have to use the mean and the standard deviation of the hypergeometric distribution, that is:
[tex]\mu = \frac{nk}{N}[/tex]
[tex]\sigma = \sqrt{\frac{nk(N-k)(N-n)}{N^2(N-1)}}[/tex]
In this question:
88 + 88 = 176 students, which means that [tex]N = 176[/tex]
88 non-history majors, which means that [tex]k = 88[/tex]
44 students are selected, which means that [tex]n = 44[/tex]
Mean and standard deviation:
[tex]\mu = \frac{44*88}{176} = 22[/tex]
[tex]\sigma = \sqrt{\frac{44*88*(176-88)*(176-44)}{176^2(175-1)}} = 2.88[/tex]
What is the probability that at least 22 of the 44 students selected are non-history majors?
Using continuity correction, as the hypergeometric distribution is discrete and the normal is continuous, this is [tex]P(X \geq 22 - 0.5) = P(X \geq 21.5)[/tex], which is 1 subtracted by the p-value of Z when X = 21.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{21.5 - 22}{2.88}[/tex]
[tex]Z = -0.17[/tex]
[tex]Z = -0.17[/tex] has a p-value of 0.4325
1 - 0.4325 = 0.5675
0.5675 = 56.75% probability that at least 22 of the 44 students selected are non-history majors.
if point B is the midpoint of points A and C, find the value of x and AC. AB= 5x - 2, BC= 9x -10
9514 1404 393
Answer:
x = 2AC = 16Step-by-step explanation:
The midpoint divides the segment into two equal lengths:
AB = BC
5x -2 = 9x -10
8 = 4x
2 = x
AB = 5(2) -2 = 8
AC = 2AB = 2(8) = 16
If 8x+5(3+x)-a=15+5x, then a = ?
Answer:
a = 8x
if you want to find x also, then x = a/8
Step-by-step explanation:
If the terminal side of an angle (θ) goes through the point (4 , -3) what is (θ)?
Answer:
The family of directions of the given vector is represented by [tex]\theta = 323.130^{\circ} \pm 360\cdot i[/tex], [tex]\forall \,i\in \mathbb{N}_{O}[/tex].
Step-by-step explanation:
According to the given information, vector stands in the 4th Quadrant ([tex]x > 0[/tex], [tex]y < 0[/tex]) and direction of the vector ([tex]\theta[/tex]) in sexagesimal degrees, is determined by following definition:
[tex]\theta = 360^{\circ} - \tan^{-1} \left(\frac{|y|}{|x|} \right)\pm 360\cdot i[/tex], [tex]\forall \,i\in \mathbb{N}_{O}[/tex]
Please notice that angle represents a function with a periodicity of 360°.
If we know that [tex]x = 4[/tex] and [tex]y = -3[/tex], then the direction of the vector is:
[tex]\theta = 360^{\circ}-\tan^{-1}\left(\frac{|-3|}{|4|} \right)\pm 360\cdot i[/tex]
[tex]\theta = 323.130^{\circ} \pm 360\cdot i[/tex]
The family of directions of the given vector is represented by [tex]\theta = 323.130^{\circ} \pm 360\cdot i[/tex], [tex]\forall \,i\in \mathbb{N}_{O}[/tex].
Copy center charges $0.08 a page for machine fed copies and $0.20 for hand fed copies.If Logan's bill for 80 copies of his movie script is $13, how many copies of each type were made?
Answer:
machine fed copies = 25, hand fed copies = 55
Step-by-step explanation:
let machine fed = x, hand fed = y
0.08x+0.2y = 13 (1)
x+y = 80
x= 80-y (2)
sub (2) into (1)
0.08(80-y)+0.2y=13
6.4-0.08y+0.2y=13
0.12y=6.6
y = 55
sub y=55 into eqn 2
x = 80-55 = 25
which function is positive for the entire interval (-3,-2)
Answer:
There can be several such functions; however, the basic condition that needs to be met for a function to be positive for the interval [–3, –2] is that it should be multiplied by (-1) Hence, one such function that is positive for the entire interval is f(x) = -x
Step-by-step explanation:
Coefficient and degree of the polynomial
Answer:
The leading coefficient is -8 as it is a mix of x and cardinal, if it was x alone then it wouldn't be the coefficient, we would use the next number shown.
If it was just a number and no x then it would still be the coefficient.
The degree is 9 as it is the highest power shown.
Step-by-step explanation:
See attachment for examples
please help! 50 points!
Answer:
a) forming a bell
b) 5
c) 4.7
d) mean
is the correct answer
pls mark me as brainliest
can someone help me, please?
Answer:
0
2
-1
Step-by-step explanation:
from f(0) we find that
y = mx - 1
from f(-1) we find that the equation is
y = -3x - 1
1)
inverse f(x) :
x = -3y - 1
y = -(x + 1) / 3 x = -1
y = -(-1 + 1) / 3
y = 0
2)
y also equal to 0 since x = -1
3)
f^-1(2) = -(2+1) / 3
= -3/3
= -1
f(-1) = 2
8x=3x²-1 plz help me show your work
Answer:
Step-by-step explanation:
3 times 8= 24 • 24 = 576 - 1 =575
or
3•8=24•2=48-1=47
not sure
Answer:
The answer is [tex]x=\frac{4(+-)\sqrt{19} }{3}[/tex] in exact form or [tex]x=2.7863[/tex], [tex]x=-0.1196[/tex] in decimal form.
Step-by-step explanation:
To solve this equation, start by moving all expression to the left side of the equation, which will include subtracting [tex]3x^2[/tex] and adding 1 to both sides of the equation. The equation will look like [tex]8x-3x^2+1=0[/tex].
Then, use the quadratic formula to find the solutions to the equation. The quadratic formula looks like [tex]\frac{-b(+-)\sqrt{b^2-4ac} }{2a}[/tex].
For this problem, the quadratic variables are as follows:
[tex]a=-3\\b=8\\c=1[/tex]
The next step is to substitute the values [tex]a=-3[/tex], [tex]b=8[/tex], and [tex]c=1[/tex] into the quadratic formula and solve for x. The quadratic formula will look like [tex]\frac{-8(+-)\sqrt{8^2-4(-3)(1)} }{2*-3}[/tex]. To simplify the equation, start by simplifying the numerator, which will look like [tex]x=\frac{-8(+-)2\sqrt{19} }{2*-3}[/tex]. Then, multiply 2 by -3 and simplify the equation, which will look like [tex]x=\frac{4(+-)\sqrt{19} }{3}[/tex]. The final answer is [tex]x=\frac{4(+-)\sqrt{19} }{3}[/tex] in exact form. In decimal form, the final answer is [tex]x=2.7863[/tex], [tex]x=-0.1196[/tex].
What is the sum of the infinite geometric series?
Answer:
-6
Step-by-step explanation:
a1= -3
r= -(3/2)/-3 = 0.5
r>-3
s= a1/1-r
= -3/1-0.5
=-6
Evaluate the expression: y – y ÷ 1 + x Use x = 7 and y = 3
Hi ;-)
[tex]x=7 \ and \ y=3\\\\y-y:1+x=3-3:1+7=3-3+7=0+7=\boxed7[/tex]
Find the equation (in terms of x) of the line through the points (-2,-3) and (4,-1)
Answer:
y = 1/3x - 7/3
Step-by-step explanation:
y2 - y1 / x2 - x1
-1 - (-3) / 4 - (-2)
2/6
= 1/3
y = 1/3x + b
-1 = 1/3(4) + b
-1 = 4/3 + b
-7/3 = b
Assume that two marbles are drawn without replacement from a box with 1 blue, 3 white, 2 green, and 2 red marbles. Find the probability that the first marble is white and the second marble is blue.
Answer:
3/56
Step-by-step explanation:
Probability is the ratio of the number of possible outcome to the number of total outcome.
Given that two marbles are drawn without replacement from a box with 1 blue, 3 white, 2 green, and 2 red marbles.
The total number of marbles in the box
= 1 + 3 + 2 + 2
= 8 marbles
The probability that the first marble is white and the second marble is blue
= 3/8 * 1/7
= 3/56
please help I have 3 mins left
Answer:
the first one is 3.7 x 10^-4
and the second one is 3.7 x 10^4
explanation:
when we have decimals we are going backward,
therefore "0.00037" would be a negative number
to find the scientific notation form, we have to move the decimal over to the left untill we get 3.7
it took 4 moves to the right to get to 3.7, and since were dealing with decimals it will be negative,
so the first one is 3.7 x 10^4
the second one however is not a decimal so it will be a positive exponent.
now remember that there is always a decimal after a number we might just not see it.
so, going from the very end of the number it takes us 4 moves to the left to get to 3.7
so,
the second one will be 3.7 x 10^4
hope this helped :)
Question 17 of 25
Solve the inequality. Enter the answer as an inequality that shows the value of
the variable; for example f>7, or 6 < w. Where necessary, use <= to write s
and use >= to write .
V-(-5) <-9
Answer here
I
SUBMIT
Answer:
v-(-5)<-9
v- remove brackets -5
v- -5= -4 +5 ( opposite operation)
v- = -4
v< -4
FX) is defined by the equation f(x) = 4x2 - 2x +17. What effect will multiplying
f(x) by 0.5 have on the graph?
A. The graph will be stretched horizontally.
B. The graph will be compressed horizontally.
C. The graph will be stretched vertically.
D. The graph will be compressed vertically.
Step-by-step explanation:
the graph will be compressed vertically
Find the area of the shape shown below.
Answer:
28 units²
Step-by-step explanation:
Area of trapezoid =
2(8 + 4)/2 = 12
Area of rectangle =
2 x 8 = 16
16 + 12 = 28
If my answer is incorrect, pls correct me!
If you like my answer and explanation, mark me as brainliest!
-Chetan K
The figure shows an equilateral triangle with its sides as indicated. find the length of each side of the triangle .
I Will Mark Brainliest
Answer:
21
Step-by-step explanation:
All three sides are equal
2x-7 = x+y-9 = y+5
Using the last two
x+y-9 = y+5
Subtract y from each side
x+y-9-y = y+5-y
x-9 = 5
Add 9 to each side
x -9+9 = 5+9
x=14
We know the side length is
2x-7
2(14) -7
28-7
21
The side length is 21
Calls to a customer service center last on average 2.3 minutes with a standard deviation of 2 minutes. An operator in the call center is required to answer 76 calls each day. Assume the call times are independent.
What is the expected total amount of time in minutes the operator will spend on the calls each day?
What is the standard deviation of the total amount of time in minutes the operator will spend on the calls each day? Give your answer to four decimal places.
What is the approximate probability that the total time spent on the calls will be less than 166 minutes? Give your answer to four decimal places. Use the standard deviation as you entered it above to answer this question.
What is the value c such that the approximate probability that the total time spent on the calls each day is less than c is 0.95? Give your answer to four decimal places. Use the standard deviation as you entered it above to answer this question.
Answer:
The expected total amount of time in minutes the operator will spend on the calls each day is of 174.8 minutes.
The standard deviation of the total amount of time in minutes the operator will spend on the calls each day is of 17.4356 minutes.
0.3085 = 30.85% approximate probability that the total time spent on the calls will be less than 166 minutes.
The value c such that the approximate probability that the total time spent on the calls each day is less than c is 0.95 is [tex]c = 203.4816[/tex]
Step-by-step explanation:
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.
n instances of a normally distributed variable:
For n instances of a normally distributed variable, the mean is:
[tex]M = n\mu[/tex]
The standard deviation is:
[tex]s = \sigma\sqrt{n}[/tex]
Calls to a customer service center last on average 2.3 minutes with a standard deviation of 2 minutes.
This means that [tex]\mu = 2.3, \sigma = 2[/tex]
An operator in the call center is required to answer 76 calls each day.
This means that [tex]n = 76[/tex]
What is the expected total amount of time in minutes the operator will spend on the calls each day?
[tex]M = n\mu = 76*2.3 = 174.8[/tex]
The expected total amount of time in minutes the operator will spend on the calls each day is of 174.8 minutes.
What is the standard deviation of the total amount of time in minutes the operator will spend on the calls each day?
[tex]s = \sigma\sqrt{n} = 2\sqrt{76} = 17.4356[/tex]
The standard deviation of the total amount of time in minutes the operator will spend on the calls each day is of 17.4356 minutes.
What is the approximate probability that the total time spent on the calls will be less than 166 minutes?
This is the p-value of Z when X = 166.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
For this problem:
[tex]Z = \frac{X - M}{s}[/tex]
[tex]Z = \frac{166 - 174.8}{17.4356}[/tex]
[tex]Z = 0.5[/tex]
[tex]Z = 0.5[/tex] has a p-value of 0.6915.
1 - 0.6915 = 0.3085.
0.3085 = 30.85% approximate probability that the total time spent on the calls will be less than 166 minutes.
What is the value c such that the approximate probability that the total time spent on the calls each day is less than c is 0.95?
This is X = c for which Z has a p-value of 0.95, so X = c when Z = 1.645. Then
[tex]Z = \frac{X - M}{s}[/tex]
[tex]1.645 = \frac{c - 174.8}{17.4356}[/tex]
[tex]c - 174.8 = 1.645*17.4356[/tex]
[tex]c = 203.4816[/tex]
The value c such that the approximate probability that the total time spent on the calls each day is less than c is 0.95 is [tex]c = 203.4816[/tex]
Find the sum of ∑3/k=0 k^2
Answer:
[tex]14[/tex]
Step-by-step explanation:
Given
[tex]\displaystyle \sum_{k=0}^3k^2[/tex]
Let's break down each part. The input at the bottom, in this case [tex]k=0[/tex], is assigning an index [tex]k[/tex] at a value of [tex]0[/tex]. This is the value we should start with when substituting into our equation.
The number at the top, in this case 3, indicates the index we should stop at, inclusive (meaning we finish substituting that index and then stop). The equation on the right, in this case [tex]k^2[/tex], is the equation we will substitute each value in. After we substitute our starting index, we'll continue substituting indexes until we reach the last index, then add up each of the outputs produced.
Since [tex]k=0[/tex] is our starting index, start by substituting this into [tex]k^2[/tex]:
[tex]0^2=0[/tex]
Now continue with [tex]k=1[/tex]:
[tex]1^1=1[/tex]
Repeat until we get to the ending index, [tex]k=3[/tex]. Remember to still use [tex]k=3[/tex] before stopping!
Substituting [tex]k=2[/tex]:
[tex]2^2=4[/tex]
Substituting [tex]k=3[/tex]:
[tex]3^2=9[/tex]
Since 3 is the index we end at, we stop here. Now we will add up each of the outputs:
[tex]0+1+4+9=\boxed{14}[/tex]
Therefore, our answer is:
[tex]\displaystyle \sum_{k=0}^3k^2=0+1+4+9=\boxed{14}[/tex]
Answer:
14
Step-by-step explanation:
∑3/k=0 k^2
Let k=0
0^2 =0
Let k = 1
1^2 =1
Let k =2
2^2 = 4
Let k = 3
3^2 = 9
0+1+4+9 = 14
In the arithmetic sequence -7, -6, -5 what term is 2?
The term 2 is the ___th term of the sequence
Answer:
10th term
Step-by-step explanation:
The equation of the arithmetic sequence is an=-7+(n-1)*1=-8+n, plugging in 2 and solving for n we have
2=-8+n, n=10
please help, will give brainliest!!!!
Answer:
3
Step-by-step explanation:
3 - 3/x
----------------
1 - 1/x
Multiply the top and bottom by x
x(3 - 3/x)
----------------
x(1 - 1/x)
3x -3
------------
x-1
Factor the numerator
3(x-1)
-------
x-1
Cancel like terms
3
-----
1
3
What does si mean in temperature
Answer:
The kelvin (abbreviation K), also called the degree Kelvin (abbreviation, o K), is the SI unit of temperature. One Kelvin is 1/273.16 (3.6609 x 10 -3 ) of the thermodynamic temperature of the triple point of pure water (H 2 O). The ampere (abbreviation, A) is the SI unit of electric current.
Answer:
kelvin is si unit of tempreature
What is the dimension of the null space Null (A) of A =
Answer:
the nullity of a matrix A is the demision of its null space:nullity A = dim (n(A).
12) Find the angles between 0o and 360o where sec θ = −3.8637 . Round to the nearest 10th of a degree:
Please show all work
9514 1404 393
Answer:
105.0°, 255.0°
Step-by-step explanation:
Many calculators do not have a secant function, so the cosine relation must be used.
sec(θ) = -3.8637
1/cos(θ) = -3.8637
cos(θ) = -1/3.8637
θ = arccos(-1/3.8637) ≈ 105.000013°
The secant and cosine functions are symmetrical about the line θ = 180°, so the other solution in the desired range is ...
θ = 360° -105.0° = 255.0°
The angles of interest are θ = 105.0° and θ = 255.0°.
f(x) = x - 1. Find the inverse of f(x).
Answer:
f^-1 (x) = x+1
Step-by-step explanation:
f(x) = x-1
y = x-1
Exchange x and y
x = y-1
Solve for y
Add 1 to each side
x+1 = y-1+1
x+1 = y
The inverse is x+1
f^-1 (x) = x+1
Fewer and fewer customers have been coming into the restaurant, so Bill, the manager, decides to change the entire menu. After he does this, he finds out that people loved the food, but the service has been driving people away. This represents what kind of problem in the decision-making process? O a) Failure to develop enough options O b) Failure to correctly define the problem c) Failure to act on a decision O d) Failure to evaluate the decision
Answer:
failure to correctly define the problem
Step-by-step explanation:
He changes the menu without identify that the real problem was the service.
What is the total cost of a $28 pair of jeans if the sales tax is 7.5%?
Answer:
30.10
Step-by-step explanation:
First find the amount of tax
28 * 7.5%
28 * .075
2.10
Add this to the price of the pants
28+2.10 =30.10
Answer as soon as you can. a. 162 comes just after b. What comes just before 182. lies in between 99 and 101. c.
Answer:
a. 161
b. 181
c. 100
Step-by-step explanation:
a. 162 comes just after 161 (160, 161, 162, 163...)
b. 181 comes just before 182 (180, 181, 182, 183...)
c. 100 is between 99 and 101 (98, 99, 100, 101, 102...)
Need the answer please, soon as possible
9514 1404 393
Answer:
(d) 27.4%
Step-by-step explanation:
The desired percentage is ...
(juniors for Kato)/(total juniors) × 100%
= 129/(129 +194 +147) × 100%
= (129/470) × 100% ≈ 27.4%
About 27.4% of juniors voted for Kato.
