Answer:
a) 0.0000001024 probability that he will answer all questions correctly.
b) 0.1074 = 10.74% probability that he will answer all questions incorrectly
c) 0.8926 = 89.26% probability that he will answer at least one of the questions correctly.
d) 0.0328 = 3.28% probability that Richard will answer at least half the questions correctly
Step-by-step explanation:
For each question, there are only two possible outcomes. Either he answers it correctly, or he does not. The probability of answering a question correctly is independent of any other question. This means that we use the binomial probability distribution 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.
Each question has five answers, of which only one is correct
This means that the probability of correctly answering a question guessing is [tex]p = \frac{1}{5} = 0.2[/tex]
10 questions.
This means that [tex]n = 10[/tex]
A) What is the probability that he will answer all questions correctly?
This is [tex]P(X = 10)[/tex]
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 10) = C_{10,10}.(0.2)^{10}.(0.8)^{0} = 0.0000001024[/tex]
0.0000001024 probability that he will answer all questions correctly.
B) What is the probability that he will answer all questions incorrectly?
None correctly, so [tex]P(X = 0)[/tex]
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{10,0}.(0.2)^{0}.(0.8)^{10} = 0.1074[/tex]
0.1074 = 10.74% probability that he will answer all questions incorrectly
C) What is the probability that he will answer at least one of the questions correctly?
This is
[tex]P(X \geq 1) = 1 - P(X = 0)[/tex]
Since [tex]P(X = 0) = 0.1074[/tex], from item b.
[tex]P(X \geq 1) = 1 - 0.1074 = 0.8926[/tex]
0.8926 = 89.26% probability that he will answer at least one of the questions correctly.
D) What is the probability that Richard will answer at least half the questions correctly?
This is
[tex]P(X \geq 5) = P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 5) = C_{10,5}.(0.2)^{5}.(0.8)^{5} = 0.0264[/tex]
[tex]P(X = 6) = C_{10,6}.(0.2)^{6}.(0.8)^{4} = 0.0055[/tex]
[tex]P(X = 7) = C_{10,7}.(0.2)^{7}.(0.8)^{3} = 0.0008[/tex]
[tex]P(X = 8) = C_{10,8}.(0.2)^{8}.(0.8)^{2} = 0.0001[/tex]
[tex]P(X = 9) = C_{10,9}.(0.2)^{9}.(0.8)^{1} \approx 0[/tex]
[tex]P(X = 10) = C_{10,10}.(0.2)^{10}.(0.8)^{0} \approx 0[/tex]
So
[tex]P(X \geq 5) = P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10) = 0.0264 + 0.0055 + 0.0008 + 0.0001 + 0 + 0 = 0.0328[/tex]
0.0328 = 3.28% probability that Richard will answer at least half the questions correctly
I need help what's the answer anyone?
Answer:
B
Step-by-step explanation:
Lexi mailed a letter on Monday morning. The letter traveled 1/2 of a mile on Monday. It
traveled 3/4 more of a mile on Tuesday, reaching its destination on Tuesday afternoon. How
far did Lexi's letter travel in all?
Answer:
1 1/4 miles
Step-by-step explanation:
3/4 + 2/4 (1/2 = 2/4) = 5/4 = 1 1/4
I need help please help
Answer:
A
Step-by-step explanation:
use the formula A=pi*r^2 to find the answer
Answer:
34.54 ft2
Step-by-step explanation:
You could figure it out by simply it
In a class of 100 students 45 students read physics, 52 students read Chemistry and 15 students read both the subject. Find the number of people who student who study neither physics nor chemistry
Answer:
12
Step-by-step explanation:
First,
Add 45+52+15
Then the answer will be 112
Then -(minus) from 100
Answer:
18 students
Step-by-step explanation:
45 - 15 = 30 students only read physics
52 - 15 = 37 students only read chemistry
15 students read both
add all of them:
30 + 37 + 15 = 82
subtract the sum from 100
100 - 82 = 18
18 students doesn't study neither
work out the circumference of this circle
give your answer in terms of pi and state its units
14cm
Answer:
43.96
Step-by-step explanation:
Well, the first step is finding out the diameter. And then the basic outline is d x 3.14. So I simply just punched in 14 x 3.14 in my calculator.
Answer:
14π cm
Step-by-step explanation:
Circumference of the circle
= 2πr
= 2π(14/2)
= 14π cm
Hallar un par ordenado (x,y) que sea una solución de la ecuación.
6x+y=9
If you know how to do this please help me.
Answer:
Undefined or no values (assuming no negative zero)
Step-by-step explanation:
The absolute value of a number (a) keeps/turns it positive. A positive number can never be equal to a negative number.
What is the range for c=6t+8
Answer:
is this statistics? i will change my answer once u explain to me thank you.
Step-by-step explanation:
Answer:
Its infinite
Step-by-step explanation:
Can someone help me plsssss
Answer:
Sorry I don't know this.
Step-by-step explanation:
Answer:
wheel: radius=3/2 diameter=3 circumference=3pi
propeller: radius=24 diameter=48 circumference=48pi
orange: radius=10/pi diameter=20/pi circumference=20
Step-by-step explanation:
Can you help me please?!
30.) d=26
Take the equation
2 x (7 + d)
Now plugin 6 for d
2 x (7 + 6)
2 x (13)
26
31.) c
Take the equation
16b+8/2
Now plugin 4 for b
16(4)+8/2
64+8/2
64+4
68
20 POINTS!!!! PLEASE HELP ME!!!!!!
Please do not tell me the answer tell me how to do it with showing my work
Answer:
Step-by-step explanation:
a)
2.64÷3.3 ( said 2.64 divided by 3.3)
3.3√2.64 ( yes I know it's not the division sign but it's as close as we can get)
2.64 / 3.3
All three representations are the same. each say divide 2.64 by 3.3. If you're thinking that last one looks more like a fraction, you're right, but.. that's also what that means. I'm showing these different ways to express the idea of division b/c it's part of what is involved with showing the work and understanding it.
so, to do the above let's move the decimal point to the right .. and do we want to move it one or two places. :? one because of 3.3 or two , because of 2.64, well we want to move it so we don't have to think about it in the problem... so move it the biggest amount that you need to, get the the decimil out of both numbers.. since the 2.64 needs two moves to the right of the decimal... use 100 times to move it 2 places, If you needed 3 then use 1000, 4 , 10,000 ect ect... see the pattern?
so
100(3.3 √ 2.64 )
move the decimal point in both 2 places right
330.0 √ 264.0
I put the extra zeros in, just so you can see the decimal easy. The zeros to the right of the decimal make no difference here.
now I'll know to put the number that I use to divde with above the zero, of 264.0 .. and i'll think about how many times 3 goes into 26 ,without going over. 3*8 = 24 so I want an 8
↓ ← ← ← 0.8
330.0 √ 264.0 ( multiply 8 * 330 = 2640 )
↓ → -264 .0 ( subtract 2640 from the number above )
0
you are done with that one, since there is zero left over and 0.8 is the answer
b)
0.324 ÷ 0.27
0.27 √ 0.324
0324 / 0.27
1000( 0.27 √ 0.324)
270 √ 324.0
↓ ← ← 1.2
270 √ 324.0
↓→ - 270 ( multiply by the 1 )
↓ = 54
↓→ - 540 (multiply by the 2 )
0
since there is zero left over you are done. The answer is 1.2
C)
0.32 ÷ 0.16
0.16 √ 0.32
100(0.32 / 0.16)
↓ ← 2
16 √32
↓→ -32 ( multiply 16 * 2 = 32 )
0
zero left over you are done. the answer is 2 :)
d)
16.92 ÷ 9.4
9.4 √ 16.92
100(16.92 / 9.4)
↓ ← ← 1.8
940 √1692.0
↓→→ - 940 (multiply by 1 )
↓ 7520
↓→ - 7520 (multiply by 8 )
0
since there is zero left you are done, The answer is 1.8
that was a lot, really nobody has talked or told you how to do this before?
where is your teacher? :/
1/3 + 1/2 and I am 5 years old
Answer:
5/6
Step-by-step explanation:
How was Franklin D. Roosevelt a lasting impact even on today's society
Answer:
Franklin Delano Roosevelt, often referred to by his initials FDR, was an American politician who served as the 32nd president of the United States from 1933 until his death in 1945. A member of the Democratic Party, he won a record four presidential elections and became a central figure in world events during the first half of the 20th century. Roosevelt directed the federal government during most of the Great Depression, implementing his New Deal domestic agenda in response to the worst economic crisis in U.S. history. As a dominant leader of his party, he built the New Deal Coalition, which defined modern liberalism in the United States throughout the middle third of the 20th century. His third and fourth terms were dominated by World War II, which ended shortly after he died in office.
Step-by-step explanation:
to this ‘Great Man Theory’ it can be said that Franklin Delano Roosevelt upheld his victorious and highly regarded government through means of social, economic and political reforms, as well as ambitious personal and strategic decisions that have successfully remained influential to American society today and maintained his image as a prominent historic leader.
If Matrix A is 3 x 4, and Matrix B is 4 x 2, what is the size of matrix BA? If BA is undefined, please state so.
Answer:
Joe Mok
Step-by-step explanation:
Joe MAMA
Please help ill give BRAINLIEST. This is geometry
Answer:
A
Step-by-step explanation:
it's a 45-45-90 triangle, so the legs are the same length and the hypotenuse is the leg length times the square root of 2. Therefore y=6 and x=6*sqrt2
Look at the picture below and answer the question that is being asked
Answer:
B
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
because they are telling you that the 7th graders were randomly chosen out of everyone who rides in a car to school to be fractioned out.
PLS HELP ASAP IM RUNNING OUT OF POINTS PLSS
Answer:
x = 35°
Step-by-step explanation:
180 - (40+40) = 2x+30
180 -80 = 2x+30
100 = 2x+30
2x = 100-30
x = 70/2
x = 35°
A school buys 1,950 pencils. The pencils are sold in boxes, with 30 pencils in each box. If each box costs $4.05, what is the total cost, in dollars, that the school will pay for the pencils?
Columbia County needs 757 pieces of pipe to repair some water lines. If each box contains 3 pieces of pipe, how many boxes should the county buy?
Answer:
253 boxes
Step-by-step explanation:
757/3 = 252.33
Pls hurry I need an instant answer ASAP! Thank you
Answer:
A= -2
Step-by-step explanation:
Hope I helped!! Negitive 2
Please can yo help me I am very bad at word problems.
Answer:
1. 60, 122 feet
2. a + s = 12
6a + 4s = 59
Step-by-step explanation:
I can't do all of them but I'll do the first 2:
1.
let w be the width of the rectangle
Then the length would be 2w + 2
Using those, the perimeter would be:
2w + 2 + 2w +2 + w + w = 364
solving:
[tex]6w + 4 = 364\\6w = 360\\w = 60[/tex]
This means the length would be:
[tex]2(60)+2\\120 + 2\\122[/tex]
2.
let a be the number of adult tickets
let s be the number of student tickets
Then:
The total number of tickets is 12, so:
a + s = 12
And the total cost is 59, so:
6a + 4s = 59
30. President Ronald Reagan earned a yearly salary of 2 x 10^5 dollars as
president. He served 8 years as president. What was the total amount of
money Ronald Reagan earned as president?
A 1.6 x 106 dollars
B. 2.0 x 106 dollars
c. 1.6 x 107 dollars
D. 2.0 x 107 dollars
Answer:
a) 1.6 x 10 ^6 dollars.
Step-by-step explanation:
since President Ronald Reagan served for 8 years. So the total amount of money that he earned is 2 x 10^5 x 8 = 16 x 10 ^ 5 = 1.6 x 10^6 dollars.
In a pre-election poll, 58% of a large random sample of voters responded as planning to vote for the school enhancement millage. A 95% confidence interval was computed for the proportion of all such voters who plan to vote for the school enhancement millage. Review each of the following statements regarding the meaning of the 95% confidence level. Determine if it is a correct (true) meaning or incorrect (false).
Answer: Hello the statement related to your question is missing attached below is the statement
answer : The statement is false
Step-by-step explanation:
The statement is false
This is because a confidence interval gives a range of values for an unknown parameter.
A 95% confidence interval is calculated and it gives a lower and upper limit in which the 58% of the voters can fall into i.e. The 58% of voters can fall within the upper and lower limit of the 95% confidence interval and not exactly 95% . Hence the statement is false.
Consider the parabola given by the equation: f(x) = 2x2 + 14.0 – 4
Find the following for this parabola:
A) The vertex:
B) The vertical intercept is the point
C) Find the coordinates of the two z intercepts of the parabola and write them as a list, separated by
commas:
It is OK to round your value(s) to to two decimal places.
Answer:
Step-by-step explanation:
f(x) = 2x² + 14x - 4
= 2(x² + 7x) - 4
= 2(x² +7x + 3.5²) - 2(3.5²) - 4
= 2(x+3.5)² - 28.5
vertex (3.5, -28.5) = (7/2, -57/2)
The vertical intercept is the y-intercept, i.e., f(0) = -4.
The x-intercepts are the values of x for which y=0.
2x² + 14x - 4 = 0
x = [-14±√(14²-4(2)(-4))]/[2(2)] = [-7±√57]/2 ≅ -7.27, 0.27
g(x) = 2x
Find g(g(-3))
Can someone please give me the answer I will mark u brilliant
Answer:
p = 16.8
[tex] r \geqslant 5.5[/tex]
Step-by-step explanation:
12)
p + 2.1 = 18.9
p = 18.9 - 2.1
p = 16.8
13)
[tex]r \geqslant 5.5[/tex]
Executives for a grocery store chain want to survey their employees about a new policy regarding break times. To
get a representative sample of 40 employees, they randomly select 10 people from each of the different job titles at
the store (cashier, bagger, stocker, and manager). Which sampling method was used?
O cluster sampling
O simple random sampling
O stratified random sampling
O systematic random sampling
Answer:
Stratified random
Step-by-step explanation:
got it right
Answer:
C
Step-by-step explanation:
Which answers describe the shape below? Check all that apply.
O A. Trapezoid
O B. Parallelogram
O c. Square
D. Quadrilateral
E. Rhombus
F. Rectangle
Answer:
Square, Quadrilateral, Rhombus, Rectangle
Step-by-step explanation:
Given the triangle shown below, find the length of [BC]
Hyp²=ADJ²+OPP²
28²=17²+X²
784=289+x²
x²=784-289
x²=495
x=22
here is your answer 22
5 members or 20% of the math league did not come to the meet. how many total members are there
5 = (20%) x (total)
5 = (0.20) x (total)
Divide each side by (0.20):
Total = (5 / 0.20)
Total = 25