Complete Question
Assume that random guesses are made for 7 multiple-choice questions on a test with 5 choices for each question, so that there are n=7 trials, each with probability of success (correct) given by p=0.20. Find the probability of no correct answers.
Answer:
The probability is [tex]P(X = 0 ) = 0.210[/tex]
Step-by-step explanation:
From the question we are told that
The number of trial is n = 7
The probability of success is p = 0.20
Generally the probability of failure is
[tex]q = 1- 0.20[/tex]
[tex]q = 0.80[/tex]
Given that this choices follow a binomial distribution as there is only two probabilities i.e success or failure
Then the probability is mathematically represented as
[tex]P(X = 0 ) = \left n} \atop {}} \right. C_0 * p^{0} * q^{n- 0}[/tex]
[tex]P(X = 0 ) = \left 7} \atop {}} \right. C_0 * (0.2)^{0} * (0.8)^{7- 0}[/tex]
Here [tex]\left 7} \atop {}} \right. C_0 = 1[/tex]
=> [tex]P(X = 0 ) = 1 * 1* (0.8)^{7- 0}[/tex]
=> [tex]P(X = 0 ) = 0.210[/tex]
The table above shows the percent of the area of a town
devoted to three uses. If the area devoted to business use
is 7,200 acres less than the area devoted to residential
use, what is the area, in acres, devoted to government
use?
A) 1,400
B) 1,800
C) 5,200
D) 44,000
=========================================================
Explanation:
Let
r = area devoted to residential use
This variable is some positive real number, and it represents the area in acres.
Your teacher says that " the area devoted to business use is 7,200 acres less than the area devoted to residential use"
This means the expression r-7200 represents the area for business use
Note the jump from 25% to 65% is 65/25 = 2.6, meaning that we multiply by 2.6 when going from the business area to the residential area.
So we'll multiply by 2.6 to go from r-7200 to r
We'll have this equation
2.6(r-7200) = r
because it's effectively saying
2.6*(business area) = residential area
--------------------------
Let's isolate r
2.6(r-7200) = r
2.6r-2.6*7200 = r
2.6r - 18720 = r
2.6r - r = 18720
1.6r = 18720
r = 18720/(1.6)
r = 11700
We'll use 11700 acres for the residential portion.
And also r-7200 = 11700-7200 = 4500 acres are set aside for the business district.
--------------------------
The largest region (residential) uses 11700 acres of land.
Note the jump from 10% to 65% involves a multiplier of 6.5 because 65/10 = 6.5
So if g is the amount of government land used, then,
6.5g = r
6.5g = 11700
g = 11700/(6.5)
g = 1800
1800 acres of land are for government use
This is why the answer is choice B.
The area, in acres, devoted to government use is 1800.
Option (B) is correct.
To find the area.
What is percentage?Percentage, a relative value indicating hundredth parts of any quantity.
Given that:
Let
r = area devoted to residential use
This variable is some positive real number, and it represents the area in acres.
This means the expression r-7200 represents the area for business use
Note the jump from 25% to 65% is 65/25 = 2.6, meaning that we multiply by 2.6 when going from the business area to the residential area.
To multiply by 2.6 to go from r-7200 to r
The equation is
2.6(r-7200) = r
because it's effectively saying
2.6*(business area) = residential area
--------------------------
Let's isolate r
2.6(r-7200) = r
2.6r-2.6*7200 = r
2.6r - 18720 = r
2.6r - r = 18720
1.6r = 18720
r = 18720/(1.6)
r = 11700
We'll use 11700 acres for the residential portion.
And also r-7200 = 11700-7200 = 4500 acres are set aside for the business district.
The largest region (residential) uses 11700 acres of land.
Note the jump from 10% to 65% involves a multiplier of 6.5 because 65/10 = 6.5
So if g is the amount of government land used, then,
6.5g = r
6.5g = 11700
g = 11700/(6.5)
g = 1800
So, the area, in acres, devoted to government use is 1800.
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what is an example of a quintic bionomial?
Write a linear(y =mx + b) quadratic (y = ax exponent 2) or exponential (y = a(b) x) function that models the data HELP
Answer:
y = 48x + 36
Step-by-step explanation:
m = 48
y = 48x +36
A concern of Major League Baseball is that games last too long. Some executives in the league's headquarters believe that the mean length of games this past year exceeded 3 hours (180 minutes). To test this, the league selected a random sample of 80 games and found the following results: = 193 minutes and s = 16 minutes.
Based on these results, if the null hypothesis is tested using an alpha level equal to 0.10, which of the following is true?
a. The null hypothesis should be rejected if xbar > 182.31.
b. The test statistic is t = 1.2924.
c. Based on the sample data, the null hypothesis cannot be rejected.
d. It is possible that when the hypothesis test is completed, a Type II statistical error has been made.
Answer:
it is possible that when the hypothesis test is completed,a type ll statistical error has been made
Calculate two iterations of Newton's Method for the function using the given initial guess. (Round your answers to four decimal places.) f(x) = x2 − 5, x1 = 2n xn f(xn) f '(xn) f(xn)/f '(xn) xn − f(xn)/f '(xn)1 2
Answer:
Step-by-step explanation:
Given that:
[tex]\mathsf{f(x) = x^2 -5 } \\ \\ \mathsf{x_1 = 2}[/tex]
The derivative of the first function of (x) is:
[tex]\mathsf{f'(x) =2x }[/tex]
According to Newton's Raphson method for function formula:
[tex]{\mathrm{x_{n+1} = x_n - \dfrac{f(x_n)}{f'(x_n)}}[/tex]
where;
[tex]\mathbf{x_1 =2}[/tex]
The first iteration is as follows:
[tex]\mathtt{f(x_1) = (2)^2 - 5} \\ \\ \mathbf{f(x_1) = -1}[/tex]
[tex]\mathtt{f'(x_1) = 2(2)} \\ \\ \mathbf{ = 4}[/tex]
[tex]\mathtt{\dfrac{f(x_1)}{f'(x_1)}} = \dfrac{-1}{4}}[/tex]
[tex]\mathbf{\dfrac{f(x_1)}{f'(x_1)} =-0.25}[/tex]
[tex]\mathtt{x_1 - \dfrac{f(x_1)}{f'(x_1)}} = \mathtt{2 - (-0.25)}}[/tex]
[tex]\mathbf{x_1 - \dfrac{f(x_1)}{f'(x_1)} = 2.25}[/tex]
Therefore;
[tex]\mathbf{x_2 = 2.25}[/tex]
For the second iteration;
[tex]\mathtt f(x_2) = (2.25)^2 -5}[/tex]
[tex]\mathtt f(x_2) = 5.0625-5}[/tex]
[tex]\mathbf{ f(x_2) =0.0625}[/tex]
[tex]\mathtt{f'(x_2)= 2(2.25)}[/tex]
[tex]\mathbf{f'(x_2)= 4.5}[/tex]
[tex]\mathtt{ \dfrac{f(x_2)}{f'(x_2)}} = \dfrac{0.0625}{4.5}}[/tex]
[tex]\mathbf{ \dfrac{f(x_2)}{f'(x_2)} = 0.01389}[/tex]
[tex]\mathtt{x_2 - \dfrac{f(x_2)}{f'(x_2)}} = \mathtt{2.25 -0.01389}}[/tex]
[tex]\mathbf{x_2 - \dfrac{f(x_2)}{f'(x_2)} = 2.2361}}[/tex]
Therefore, [tex]\mathbf{x_3 = 2.2361}[/tex]
Put the following equation of a line into slope-intercept form, simplifying all fractions.
Thanks In advance
Answer:
2x+2y=-18
2y=-2x-18
y=-x-9
hope that answers your questipn
dont hesitate to comment for more explanation about this topic.
STUCK Basic geometry A for senior year school
Answer:
(C) A reflection across a horizontal line and a horizontal translation
Step-by-step explanation:
We can see that, near the x-axis, these shapes are 3 y values away from the x-axis, meaning that if we reflect one over the x-axis we will be at the same y values as the other shape.
Reflecting these points shows that we’ve got the same shape, just skewed the one side. We can then translate this shape horizontally to get it to where we want it.
Hope this helped!
A survey of 500 randomly selected adults found that 57% say that they would take a ride in a fully self-driving car. The 95% confidence interval for the true proportion of all adults who would take a ride in a full self-driving car is found to be (0.5266, 0.6134). Can we conclude that the majority of all adults would take a ride in a fully self-driving car?
Yes; Since the confidence interval limits are both greater than 50%, we can reasonably conclude that more than half of all adults would take a ride in a fully self-driving car.
No; The data does not include all adults, so we cannot make a conclusion about the population.
No; The confidence interval limits are not large enough to determine that a majority rely only on cellular phones. The proportion would need to be much greater than 50%, and the one above is only slightly larger.
Yes; Since the proportion of adults who said yes is 57%, and this is higher than 50%, we can conclude that a majority would take a ride in a fully self-driving car.
Answer:
Yes; Since the confidence interval limits are both greater than 50%, we can reasonably conclude that more than half of all adults would take a ride in a fully self-driving car.
Step-by-step explanation:
From the question we are told that
The sample size is n = 500
The sample proportion is [tex]\r p = 0.57[/tex]
The 95% confidence interval is (0.5266, 0.6134)
Looking at the 95% confidence level interval we see that the sample proportion is within the interval and given that the confidence interval limits are both greater than 50%, we can reasonably conclude that more than half of all adults would take a ride in a fully self-driving car.
Pls help need this done hurry
Answer:
Shade 23 boxes
Step-by-step explanation:
This is the first two rows fully (all 10 boxes) and then three more from the third row.
xxxxxxxxxx
xxxxxxxxxx
xxx . . . . . . .
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HELPPP ASPPP PLZZ Select the correct answer
Answer: Choice C
[tex]\frac{2x+3}{x+2}[/tex]
===============================================
Work Shown:
[tex]h(x) = f(x) \div g(x)\\\\h(x) = \frac{f(x)}{g(x)}\\\\h(x) = \frac{2x^2-x-6}{x^2-4}\\\\h(x) = \frac{(x-2)(2x+3)}{(x-2)(x+2)}\\\\h(x) = \frac{2x+3}{x+2}\\\\[/tex]
Optional Extra Info:
Keep in mind that [tex]x \ne 2[/tex] and [tex]x \ne -2[/tex] to avoid division by zero errors. We can plug in x = 2 just fine into the simplified version of h(x), but we always need to go back to the original.
There are $400$ pages in Sheila's favorite book. The average number of words per page in the book is $300$. If she types at an average rate of $40$ words per minute, how many hours will it take to type the $400$ pages of the book?
Answer:
50hours
Step-by-step explanation:
Given that there are 400 pages in Sheila's favorite book.
The average number of words per page in the book is 300
She types an average rate of 40words per minute.
So to type 400pages of the book
Total number of words in the pages = 400×300 = 120000 words
Typing rate : 40words ------- 1minute
120000 words ----------- x minutes
Hence we have 40 × X mins = 120000 × 1min
Make X the subject
40X = 120000minutes
X = 120000/40
X = 3000minutes
Since 60minutes = 1hour
3000minutes = 3000minutes/60
= 50hours
Hence it took her 50hours to type 400pages
Solution:
The total number of words in the book is 400 x 300. Sheila types at a rate of 40 words per minute, or 40 x 60 words per hour. The number of hours it takes her is equal to the number of words divided by her rate of typing, or 400x300/40x60 = 50 hours.
Write 11 numbers in a row so that the sum of any 3 consecutive numbers is negative, while the sum of all the numbers is positive.
Answer:
Step-by-step explanation:
Hello, if I take the following
2, 2, -5, 2, 2, -5, 2, 2, -5, 2, 2
The sum is 8*2-5*3=16-15=1 > 0
and
2 + 2 -5 < 0
2 - 5 + 2 < 0
-5 + 2 + 2 < 0
2 + 2 -5 < 0
2 - 5 + 2 < 0
-5 + 2 + 2 < 0
2 + 2 -5 < 0
2 - 5 + 2 < 0
-5 + 2 + 2 < 0
2 + 2 -5 < 0
2 - 5 + 2 < 0
Hope this helps.
Do not hesitate if you need further explanation.
Thank you
The length of the shadow of a flagpole was found to be 72 feet. The shadow of a 3 foot picket fence in line with the flagpole was 4 feet. What is the height of the flagpole.
Answer:
54ft
Step-by-step explanation:
if 3foot is 4ft tall
then a shadow of 72 ft will be how tall?= x
4x =3ft by 72ft
4x= 216ft
x= 216/4
×=54
If you roll 2 dice, what is the probability the sum is a 4, 7 or 10?
Answer:
4=3
7=6
10=3
Step-by-step explanation:
P4= (3,1), (1,3), (2,2)
P7= (6,1), (4,3), (5,2), (3,4), (2,5), (1,6)
P10= (5,5), ( 6,4), (4,6)
A jar of honey is $2.40. How much do 4 jars of honey cost
Answer:
It would cost you 9.6 dollar .
I hope it is helpful mark me as brainlest and follow me for more good answer plz♥️♥️
What is the solution to this ?
Answer:
[tex]\boxed{\sf C. \ x\geq -4}[/tex]
Step-by-step explanation:
[tex]-8x+4\leq 36[/tex]
[tex]\sf Subtract \ 4 \ from \ both \ sides.[/tex]
[tex]-8x+4-4 \leq 36-4[/tex]
[tex]-8x\leq 32[/tex]
[tex]\sf Divide \ both \ sides \ by \ -8.[/tex]
[tex]\frac{-8x}{-8} \leq \frac{32}{-8}[/tex]
[tex]x\geq -4[/tex]
$88 tickets to the San Francisco 49ers game are offered at a 15%
discount. What is the sale price?
Answer:
74.80
Step-by-step explanation:
First find the discount
88 * 15%
88*.15
13.2
Subtract the discount from the original price
88-13.2
74.80
Let R be a system consisting of rational expressions. Which operations are closed for R?
Answer:
D
Step-by-step explanation:A set is said to be closed under an operation when the application of the operation between any two elements of the set leads to an element that belongs to the same set. If a set is closed under an operation, it is said to have the closure property of that operation. When we combine two rational expressions by adding, subtracting, multiplying, or dividing, we get a rational expression. This pattern indicates that rational expressions are closed for all four operations.
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Answer:
a₃ = 9
Step-by-step explanation:
The numbers in the set are referred to as { a₁, a₂, a₃, ... }
Answer:
a3 = 9 is the answer to this questionNEED HELP ASAP PLEASE!! The graph of F(x), shown below, resembles the graph of G(x) = x2, but it has
been stretched and shifted. Which of the following could be the equation of
Fx)?
10
G(X) = x2
10
Fx) = ?
Answer:
D. F(x) = ( (1/5)x)^2 - 4
Step-by-step explanation:
The standard transformation with a stretch and a shift is
F(x) = f(x/b) + k
The red curve has a vertex at (0,-4), and cuts the x-axis at (10,0)
That means that before the vertical shift (of k=-4), the vertex was at (0,0), and the curves passes through (10,4).
Substituting in the equation
F(10) = (10/b)^2 -4 = 0
solve for b
(10/b)^2-4 = 0
(10/b)= sqrt(4) = 2
b = 10/2 = 5
Therefore the transformation equation is
F(x) = (x/5)^2-4
The answer is
F(x) = ( (1/5)x)^2 - 4
Suppose we want to test the color distribution claim on the M&M’s website that a bag of plain M&M’s is made up of 10% blue, 10% orange, 10% green, 20% red, 20% yellow, and 30% brown. We select a sample of 400 plain M&M’s and found the following: Color Blue Orange Green Red Yellow Brown Frequency 30 48 55 66 70 131
Is there evidence to doubt the color distribution claimed by the website? Use =0.05
Answer:
Calculated χ² = 13.425
χ² (5,0.025) >14.45 and χ²(5,0.975) <1.24
The given data does not fall in the critical region so we accept H0 and conclude there is no evidence to doubt the color distribution claimed by the website.
Step-by-step explanation:
Color Blue Orange Green Red Yellow Brown
Frequency 30 48 55 66 70 131
Expected 40 40 40 80 80 120
H0: The bag of plain M&Ms is made up of 10% blue, 10% orange, 10% green, 20% red, 20% yellow, and 30% brown
Ha: The color distribution is not equal to the distribution stated in the null hypothesis.
Calculate chi square
χ² = (30-40)² /40 + (48-40)²/40 + (55-40)²/40 + (66-80)²/80 + (70-80)²/80 + (131-120)²/120
χ² = 2.5 + 1.6 + 5.625 + 2.45 + 1.25= 13.425
The critical region for χ² for 5 degrees of freedom with ∝= 0.05 is
χ² (5,0.025) >14.45 and χ²(5,0.975) <1.24
The given data does not fall in the critical region so we accept H0 and conclude there is no evidence to doubt the color distribution claimed by the website.
Please help will give brainliest
Complete the equation describing how
x and y are related.
X
0
1
2
3
4
у
-6
-10
-14
- 18
-22
y = [ ? ]x + [ ]
Enter the answer that belongs in [?].
Answer:
-6
Step-by-step explanation:
The equation is in slope intercept form
y = mx+b where m is the slope and b is the y intercept
The y intercept is the value when x = 0
The y value is -6 when the x value is 0
y = -4x+ (-6)
NEED HELP ASAP
Which is best described as a part of the interior of a circle bounded by an arc
and the two radii that share the are's endpoints?
Answer:
The answer is sector. B.
Good day!A right triangle has the following vertices Find the area of the triangle
(7,-3) (4,-3) (4,9)
20 pnts
Answer:
Area = 18 square units
Step-by-step explanation:
To find the area of the triangle, let's go through the following steps:
(i) Let the vertices be;
A = (7, -3)
B = (4, -3)
C = (4, 9)
(ii) The sides of the triangle are therefore,
AB, BC and CA
(iii) Using the distance formula, calculate the lengths of AB, BC and CA
[tex]AB = \sqrt{(7-4)^2 + ( -3 - (-3))^2}[/tex]
[tex]AB = \sqrt{3^2 + (0)^2}\\[/tex]
[tex]AB = \sqrt{9}[/tex]
[tex]AB = 3[/tex]
[tex]BC = \sqrt{(4-4)^2 + ( -3 - 9)^2}[/tex]
[tex]BC = \sqrt{0^2 + (-12)^2}[/tex]
[tex]BC = \sqrt{144}[/tex]
[tex]BC = 12[/tex]
[tex]CA = \sqrt{(4-7)^2 + ( 9 - (-3))^2}[/tex]
[tex]CA = \sqrt{(-3)^2 + (12)^2}[/tex]
[tex]CA = \sqrt{9 + 144}[/tex]
[tex]CA = \sqrt{153}[/tex]
[tex]CA = 12.4[/tex]
(iv) Now that we have all the sides, let's calculate the area of the triangle using the Heron's formula.
Area = [tex]\sqrt{p(p-a)(p-b)(p-c)}[/tex]
Where;
p = [tex]\frac{a + b + c}{2}[/tex]
a, b and c are the sides of the triangle.
In our case,
let
a = AB = 3
b = BC = 12
c = CA = 12.4
∴ p = [tex]\frac{3 + 12 + 12.4}{2}[/tex]
p = 13.7
Area = [tex]\sqrt{p(p-a)(p-b)(p-c)}[/tex]
Area = [tex]\sqrt{13.7(13.7-3)(13.7-12)(13.7-12.4)}[/tex]
Area = [tex]\sqrt{13.7(10.7)(1.7)(1.3)}[/tex]
Area = [tex]\sqrt{323.9639}[/tex]
Area = 17.999
Area = 18 square units
OR
To get the area of the triangle, we can use a much simpler approach.
Since the triangle is a right triangle,
(i) the hypotenuse, which is the longest side is CA = 12.4
(ii) the other two sides are AB and BC. These two sides will form the right angle.
Therefore, we can use the relation:
Area = [tex]\frac{1}{2}[/tex] x base x height
Where;
the base or height can either be AB or BC
Area = [tex]\frac{1}{2}[/tex] x 3 x 12
Area = 18 square units
PS: In a right triangle, the other two sides apart from the hypotenuse form the right angle.
Q-21: The regions of inequalities are also called:
A) Planes B) Lines C) Half planes D) None of these
Answer:
D ) none of these .. i think this help you
Kristin is building a pattern using triangles. The table shows the number of triangles in the first 4 terms of the pattern.
Term Number (7)
1 2 3 4
Number of Triangles (t) 1 3 5 7
Which formula describes the number of triangles in the nth term of the pattern?
O A n=1+2
O B. n=1+3
Oc. n = 21-1
OD n = 2t + 3
Answer:
[tex]\bold{n =2t-1}[/tex]
Step-by-step explanation:
Given table is:
[tex]\begin{center}\begin{tabular}{ c c}Term Number (t) & Number of triangles (n) \\ 1 & 1 \\ 2 & 3 \\ 3 & 5 \\ 4 & 7 \\\end{tabular}\end{center}[/tex]
i.e. when term number, t = 1, number of triangles (n) = 1
when term number, t = 2, number of triangles (n) = 3
when term number, t = 3, number of triangles (n) = 5
when term number, t = 4, number of triangles (n) = 7
If we closely look at the pattern, number of triangles (n) in each row are 1 lesser than twice of term number (t).
i.e. for [tex]t=1, n = 2\times 1 -1=1[/tex]
[tex]t=2, n = 2\times 2 -1=3[/tex]
[tex]t=3, n = 2\times 3 -1=5[/tex]
[tex]t=4, n = 2\times 4 -1=7[/tex]
Therefore, the number of triangles in the nth term will be given as:
[tex]\bold{n =2t-1}[/tex]
Answer:
an = 2t -1
Step-by-step explanation:
We are adding 2 each time
1+2 =3
3+2 = 5
5+2 = 7
an is the nth term in the sequence and t is the number of triangle
an =1+ 2(t-1)
Distribute
an = 1 +2t -2
an = 2t -1
HELP PLEASE WILL MARK BRAINLIEST
Answer:
C.
Step-by-step explanation:
since x=1 it should be -1 so C. is correct
Solve for x² in x²-3x+2=0
[tex]x^2-3x+2=0\\x^2-x-2x+2=0\\x(x-1)-2(x-1)=0\\(x-2)(x-1)=0\\x=2 \vee x=1\\\\x^2=4 \vee x^2=1[/tex]
Answer:
Step-by-step explanation:
First we try to factor x²-3x+2.
We have to look for two numbers that multiply to 2 and add -3.
The two numbers are -1 and -2.
(x-1)(x-2) = 0
x-1 = 0 -> x = 1
x-2 = -> x = 2
Now we find x^2.
(1)^2 = 1
(2)^2 =4
James has a total of 66 dollars in his piggy bank. He only has one dollar bills and two dollar bills in his piggy bank. If there are a total of 49 bills in James's piggy bank, how many one dollar bills does he have?
Answer:
32 one-dollar bills.
Step-by-step explanation:
Let x represent one-dollar bills and y represent two-dollar bills.
He has a total of 49 bills. Therefore:
[tex]x+y=49[/tex]
The total amount of money James has is 66. x is worth one dollar, while y is worth two dollars. Therefore:
[tex]1x+2y=66\\x+2y=66[/tex]
We have a system of equations. Solve by substitution:
[tex]x+2y=66\\x+y=49\\x=49-y\\(49-y)+2y=66\\y=17\\x=49-17=32[/tex]
Therefore, James has 32 one-dollar bills and 17 two-dollar bills.
Checking:
[tex]32(1)+17(2)\stackrel{?}{=}66\\32(1)+17(2)\stackrel{\checkmark}{=}66\\\\32+17\stackrel{?}{=}49\\49\stackrel{\checkmark}{=}49[/tex]
Using the insurance company's assumptions, calculate the probability that there are fewer than 3 tornadoes in a 14-year period. Round your answer to four decimal places.
Answer: 19.2222
Step-by-step explanation:
given data;
no of tornadoes = 2,1,0 because it’s fewer than 3.
period = 14 years
probability of a tornado in a calendar year = 0.12
solution:
probability of exactly 2 tornadoes
= ( 0.12 )^2 * ( 0.88 )^11 * ( 14! / 2! * 11! )
= 0.0144 * 0.2451 * 1092
= 3.8541
probability of exac one tornado
= ( 0.12 )^1 * ( 0.88 )^12 * ( 14! / 1! * 12! )
= 0.12 * 0.2157 * 182
= 12.7109
probability of exactly 0 tornado
= ( 0.12 )^0 * ( 0.88 )^13 * ( 14! / 0! * 13! )
= 1 * 0.1898 * 14
= 2.6572
probability if fewer than 3 tornadoes
= 3.8541 + 12.7109 +2.6572
= 19.2222