A bag contains 6 black, 4 blue, and 8 white marbles. What is the probability that a marble drawn from the bag will be white?
a.1/18
b.2/5
c.4/9
d.4/5
Answer:
C.4/9
Step-by-step explanation:
You add the black marbles, blue marbles, and the white marbles together, which equal 18. Out of the 18 marbles, 8 of them are white so it would be 8/18.
but you have to simplify it. 8 and 18 have 2 as the greatest common factor. 8 divided by 2 is 4 and 18 divided by 2 is 9. Finally its 4/9 since you cant simplify it even more.
The Rockwell hardness of a metal is determined by impressing a hardened point into the surface of the metal and then measuring the depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normally distributed with mean 70 and standard deviation 3. (Rockwell hardness is measured on a continuous scale.)a. If a specimen is acceptable only if its hardness is between 67 and 75, what is the probability that a randomly chosen specimen has an acceptable hardness?b. If the acceptable range of hardness is (70-c, 70+c) , for what value of c would 95% of all specimens have acceptable hardness?c. If the acceptable range is as in part (a) and the hardness of each of ten randomly selected specimens is independently determined, what is the expected number of acceptable specimens among the ten?d. What is the probability that at most eight of ten independently selected specimens have a hardness of less than73.84? [Hint: Y = the number among the ten specimens with hardness less than 73.84 is a binomial variable; what is p?]
Answer:
a) The probability that a randomly chosen specimen has an acceptable hardness is 0.7938.
b) If the acceptable range of hardness is (70-c, 70+c), then the value of c would 95% of all specimens have an acceptable hardness of 5.88.
c) Expected number of acceptable specimens among the ten is 7.938.
d) Binomial with n = 10 and p = P(X < 73.84)
[tex]p = P(Z <(73.84 - 70) / 3 ) = P(Z < 1.28) = 0.8997\\\\P(X <= 8) = 1 - P(X = 9) - P(X = 10)\\= 0.2650635[/tex]
Step-by-step explanation:
a )
[tex]P(67 < X< 75) = P( (67 - 70) / 3 < X < (75 - 70) / 3 )\\\\= P( - 1 < Z < 1.67) = 0.9525 - 0.1587 = 0.7938[/tex]
b )
[tex]c = 1.96 * 3 = 5.88[/tex] { Since Z = 1.96 for 95% CI refer table.}
c )
Expected number of acceptable specimens among the ten [tex]= 10 * P(67 < X< 75) \\\\= 10 * 0.7938 = 7.938[/tex]
d )
Binomial with n = 10 and p = P(X < 73.84)
[tex]p = P(Z <(73.84 - 70) / 3 ) = P(Z < 1.28) = 0.8997\\\\P(X <= 8) = 1 - P(X = 9) - P(X = 10)\\= 0.2650635[/tex]
The moment generating function for health care costs experienced by a policyholder is given as follows:
Mx(t)= (4/4-t)^3
An insurer reimburses the policyholder for 70% of health care costs experienced by the policyholder. Calculate the expected reimbursement by the insurer for a policyholder.
Answer:
0.525 = 52.5%
Step-by-step explanation:
Moment generating function ( Mx(t) ) = ( 4 / 4-t)^3
Reimbursement by Insurer = 70%
Determine the expected reimbursement by insurer for policyholder
d/dx (Mx(t) ) = d/dt ( 4 / 4-t)^3 = d/dt (1 - t/4 )^-3
= 3/4 ( 1 - t/4 )^-4 = 3/4
as t → 0
Given that the insurer reimburses 70% = 0.7
expected reimbursement = 0.7 * 3/4 = 0.7 * 0.75 = 0.525
Evaluate: 11c+5a-8 for a=4 and c=-6
Answer:
- 54
Step-by-step explanation:
11 c + 5 a - 8
11 × -6 + 5 × 4 - 8 (given :- a = 4 and b = -6)
- 66 + 20 - 8
- 54
carol and jada sold raffle tickets to raise money for a new playground carol sold 2045 tickets jada sold 356 more than carol how many did jada sell
A pizza company runs a marketing campaign based on their delivery time for pizzas. They claim that they will deliver a pizza within 30 minutes of ordering or it is free. In practice the time it takes to prepare a pizza and it being delivered is normally distributed with mean 25 minutes and standard deviation 3 minutes. What is the probability a pizza is delivered for free?On a particular Sunday, 40 pizzas were ordered. What is the probability that more than 2 were delivered for free?If the company wants to reduce the proportion of pizzas that are delivered free to 1%, what should the delivery time be advertised as?
Answer:
0.0475 = 4.75% probability a pizza is delivered for free.
0.2955 = 29.55% probability that more than 2 were delivered for free.
The delivery time should be advertised as 32 minutes.
Step-by-step explanation:
To solve this question, we need to understand the binomial distribution and the normal distribution.
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.
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.
Normally distributed with mean 25 minutes and standard deviation 3 minutes.
This means that [tex]\mu = 25, \sigma = 3[/tex]
What is the probability a pizza is delivered for free?
More than 30 minutes, which is 1 subtracted by the p-value of Z when X = 30.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{30 - 25}{3}[/tex]
[tex]Z = 1.67[/tex]
[tex]Z = 1.67[/tex] has a p-value of 0.9525
1 - 0.9525 = 0.0475
0.0475 = 4.75% probability a pizza is delivered for free
What is the probability that more than 2 were delivered for free?
Multiple pizzas, so the binomial probability distribution is used.
0.0475 probability a pizza is delivered for free, which means that [tex]p = 0.0475[/tex]
40 pizzas, which means that [tex]n = 40[/tex]
This probability is:
[tex]P(X > 2) = 1 - P(X \leq 2)[/tex]
In which
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2)[/tex]
So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{40,0}.(0.0475)^{0}.(0.9525)^{40} = 0.1428[/tex]
[tex]P(X = 1) = C_{40,1}.(0.0475)^{1}.(0.9525)^{39} = 0.2848[/tex]
[tex]P(X = 2) = C_{40,2}.(0.0475)^{2}.(0.9525)^{38} = 0.2769[/tex]
Then
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2) = 0.1428 + 0.2848 + 0.2769 = 0.7045[/tex]
[tex]P(X > 2) = 1 - P(X \leq 2) = 1 - 0.7045 = 0.2955[/tex]
0.2955 = 29.55% probability that more than 2 were delivered for free.
If the company wants to reduce the proportion of pizzas that are delivered free to 1%, what should the delivery time be advertised as?
The 99th percentile, which is X when Z has a p-value of 0.99, so X when Z = 2.327.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]2.327 = \frac{X - 25}{3}[/tex]
[tex]X - 25 = 2.327*3[/tex]
[tex]X = 32[/tex]
The delivery time should be advertised as 32 minutes.
Ms.James shared 5/8 of the candies she had in a bag and had 15 left.How many candies did she have before sharing?
Answer:
40
Step-by-step explanation:
If you take 15, and divide it by the 3 out of the 3/8 left, you get 5. You then multiply 5 by 8 to get the full amount of candies she had before sharing, 40.
I hope this helped!
Thanks!
Your friend in answering,
~Steve
Answer:
40.
Step-by-step explanation:
If 15 candies are the rest of 3/8, then the total candies were 40.
What is the slope of the line represented by the equation f(x) = -3x + 7?
A -7
B -3
C 3
D 7
Answer:
-3
Step-by-step explanation:
in these equations the slope is multiplied by x which is -3 in this one.
Answer:
[tex]-3[/tex]
Step-by-step explanation:
The equation of a line is [tex]y=mx+b[/tex], and m is the gradient which is the slope. Hence, the number with x is the slope, which is [tex]-3[/tex].
Hope that helped.
Which expression is not equivalent to 8 + (n – 4)?
12+n
n+4
(8 + n) – 4
(8 – 4) +n
Answer: n+4
Step-by-step explanation:
by how much is 2690 less than 3780
Step-by-step explanation:
Subtract 2690 from 3780
3780
-2690
=1090
at the present time, gerald is eight less than five times his nephews age. seven years ago gerald was 9 times his nephews age.
(A)if g represents geralds age now and n represents his nephews age today. use a system of equations that could be used to model this scenario?
(B)than use the equations to determine algebraically the ages of both Gerald and his nephew.
(C)than determine in how many years Gerald will be three times as old as his nephew?
What you know about rollin' down in the deep?
When your brain goes numb, you can call that mental freeze
When these people talk too much, put that sh*t in slow motion, yeah
I feel like an astronaut in the ocean, ayy
What you know about rollin' down in the deep?
When your brain goes numb, you can call that mental freeze
When these people talk too much, put that sh*t in slow motion, yeah
I feel like an astronaut in the ocean
A team of researchers wants to determine whether pet owners are generally more satisfied with their lives than non-pet owners. To test their theory, the researchers randomly select 500 pet owners and 500 non-pet owners from several major metropolitan areas in the country. The researchers then interview the individuals, asking them a series of questions. Each response is assessed with a point value that is later translated to a satisfaction indicator. Of the pet owners surveyed, 380 of the 500 were found to be satisfied with their lives, while 336 of the 500 non-pet owners were found to be satisfied.
Would this study be considered an experiment or an observational study?
Answer:
observational study
Step-by-step explanation:
is the sum of two rational numbers sometimes zero ture or false?
Answer:
True.
Step-by-step explana
-4/5 + 4/5 is 0
The side of an equilateral triangle is 12. Its area is
Select one:
a. 144
b. 72
c. 36 √3
d. 48
Answer:
area is 1/2bh
in an euqilateral triangle, all sides are equal so base and height are 12
1/2 x 12 x 12
1/2 x 144= 72 (B)
Answer: Choice C. [tex]36\sqrt{3}[/tex]
This is the same as writing 36*sqrt(3)
===================================================
Work Shown:
x = 12 = side length of equilateral triangle
A = area of equilateral triangle
A = 0.25*sqrt(3)*x^2
A = 0.25*sqrt(3)*12^2
A = 0.25*sqrt(3)*144
A = 0.25*144*sqrt(3)
A = 36*sqrt(3) .... answer is choice C
Side note: the area approximates to 62.354 square units.
course
Look at the following number line:
- 10
-5
0
5
10
What are two ways to write the inequality graphed?
x>-1 and -1
XS-1 and -12X
x < -1 and -1 > X
x2-1 and -1 5x
first and last one i think
Factor this polynomial.
.-2x2 - 7x-3
Answer:
Its B
Step-by-step explanation:
Mark as Brainllest!!
Find the difference of (4.2x10^3)-(2.7x10^3)
Show work!
Step-by-step explanation:
Is it helpful ?
plz let me know
Which of the following expressions have a difference of 5? Check all that apply.
VX
0-3-(-8)
-2-3
1-(-4)
07-(-2)
9514 1404 393
Answer:
A, C
Step-by-step explanation:
A: -3 -(-8) = -3 +8 = 5
B: -2 -3 = -5
C: 1 -(-4) = 1 +4 = 5
D: 7 -(-2) = 7 +2 = 9
__
Differences A and C are 5.
Answer: A: -3- (-8)
B:1 -(-4)
Step-by-step explanation:
in A your subtracting them in B your adding them
Can I have help I am stuck on this problem It would mean the world if u helped me and tysm!! =-)
Answer:
Step-by-step explanation:
Wage = rate / hr * the number of hours worked.
Wage = ?
rate = 15.45
time = 29.25 hours
Wage = 15.45 * 29.25
Wage = 451.91
Please help! What is the domain of the function shown in the graph?
Answer:
nnmb cgchmfxmgfmv vb , mnio qrstuvwxyz
abcdefghijklmnoprstuvxxyz
Step-by-step explanation:
now i know my abcs next time wont you sing with me
PLEASE HELPPPPpdododp
Answer:
f(x) - g(x) = x^3 - 3x^2 - 4x - 4
Step-by-step explanation:
f(x) - g(x)
x^3 - 2x^2 - 3x - 5 - ( x^2 + x - 1 )
x^3 - 2x^2 - 3x - 5 - x^2 - x + 1
x^3 - 3x^2 - 4x - 4
The table shown gives values of the function y=g(x) for selected values of x.
Answer: C
Explanation:
A is eliminated because of 3 and 24, 3^2 is 9 and 9 times 3 isnt 24
B is eliminated because of 1 and 6, 2 plus 3 is 5 not 6
C works for all the number sets
D is eliminated because of 1 and 6, again 3 plus 2 is 5 not 6
When we expand (2x + 1/2)^6, what is the coefficient on the x^4 term?
Answer: The coefficient before x^4 is 60
Step-by-step explanation:
Hey! So I am not an expert at this, but you have to use the binomial theorem
I have attached of the Pascals Triangle (one shows the row numbering as well)
Basically in a pascal triangle, you add the two numbers above it to get the next number below
As you can see, the rows start from 0 instead of 1
The 6th row contains the numbers 1, 6, 15, 20, 15, 6, 1 which would be the coefficient terms
NOTE: the exponents always add to 6, the first term starts at 6 and decrease it's exponent by 1 each time (6, 5, 4, 3, 2, 1, 0) and the second term increases it's exponent by 1 each time (0, 1, 2, 3, 4, 5, 6)
Using this information the third term from the sixth row (15) would be where it is x^4 (I have circled it on the second image)
It would be 15 × 2^4 × (1/2)^2 = 60
The reason why it is 2^4 and (1/2)^2 is because the third term has the exponents 4 and 2 (bolded on the NOTE) which means that the first term must be put to the power of 4 and the second term must be put to the 2nd power
Sorry for the lousy explanation. I really hope this makes sense! Let me know if this helped :)
Which is the graph of f(x) = 2 (4)?
5
40.4)
404)
4
(4,4)
3
3
3 2
2
2
2
(2.1)
6,2)
1
5 -4 -3 -2 -14
1
3
4
-5 4 -3 -2 -14
234
-5 6 -3 -2 -14
2
3
4
5
X
-2
-2
نا دیا
-3
-3
4
W4
-5
5
Tu
5
4
(
24)
Answer:
The Third one
Step-by-step explanation:
Your Welcome :)
Graph of the function is attached below.
Correct option is D.
What is exponential function?As the name suggests, the exponential function contains an exponent. Note, however, that the exponential function has a constant as its base and a variable as its exponent, not vice versa (if a function has a variable as its base and a constant as its exponent, it is a power function). The exponential function can be in one of the following forms:
Definition of exponential function
In mathematics, an exponential function is a function of the form f(x) = aˣ. where "x" is a variable and "a" is a constant called the base of the function, which must be greater than 0.
Given, exponential function
f(x) = (1/4)4ˣ
exponential function is defined for x∈R
Putting x = 0
f(0) = (1/4)4⁰
f(0) = 1/4
Point on curve is (0,1/4)
Putting x = 1
f(1) = (1/4)4¹
f(1) = (1/4)4
f(1) = 1
Point on curve is (1,1)
Putting x = 2
f(2) = (1/4)4²
f(2) = (1/4)16
f(2) = 4
Point on curve is (2,4)
Putting x = 3
f(3) = (1/4)4³
f(3) = (1/4)64
f(3) = 16
Point on curve is (3,16)
Point (0, 1/4), (1, 1), (2, 4), (3, 16) can be used to draw graph of the function.
Hence, graph of the function is drawn as follows.
Learn more about exponential function here:
https://brainly.com/question/14355665
#SPJ7
Which answer describes the pattern in this sequence?
2, 1, 12, 14, ...
multiply by 2
subtract 1
add 12
multiply by 12
construct a scale of A-sharp major on a treble staff in ascending order only
Answer: In the picture from the basic music theory website's page on a-sharp major scale
Step-by-step explanation: music theory
I need help I’ll give u brainlest
Answer:
[tex]150[/tex] cubic centimeters
Step-by-step explanation:
Volume for triangular prism is [tex]V=\frac{1}{2} bhl[/tex]
[tex]V=\frac{1}{2}(6)(5)(10)[/tex]
[tex]V=\frac{1}{2} (300)[/tex]
[tex]V=150[/tex]
Hope this helps
Answer:
150 cubic centimeters
Step-by-step explanation:
The formula for the volume of a Triangular prism:
A=1/2*b*h*l
plug everything in
1/2*6*5*10=150 Cubic centimeters
help whats the answer??
Answer:
2 7/12
Step-by-step explanation:
You have to get all the fractions to a common denominator. Smallest common denominator would be 12.
5 and 3/4 turns to 5 and 9/12
2/3 turns to 8/12
2 and 1/2 turns to 2 and 6/12
8/12 + 2 6/12 = 3 2/12
5 9/12 - 3 2/12 = 2 7/12
2 7/12 being the remaining amount
what is the square root of 15
Step-by-step explanation:
[tex] \sqrt{15} = 3.872983346 = 3.88[/tex]
PLEASE HELP WILL GIVE BRAINLIEST
Answer:
Check explanation
Step-by-step explanation:
I'll give you my way of solving it and you can figure it out from there.
<CEA = <DEB due to vertical angles
AE = ED due to midpoint theorem
<CAD = <ADB due to alternating angles theorem
thus two triangles congruent due to ASA
