Answer:
x<-12
Step-by-step explanation: hope this helps!
The lifespan, in years, of a certain computer is exponentially distributed. The probability that its lifespan exceeds four years is 0.30. Let f(x) represent the density function of the computer's lifespan, in years, for x>0. Determine an expression for f(x).
Answer:
The correct answer is "[tex]0.300993e^{-0.300993x}[/tex]".
Step-by-step explanation:
According to the question,
⇒ [tex]P(x>4)=0.3[/tex]
We know that,
⇒ [tex]P(X > x) = e^{(-\lambda\times x)}[/tex]
⇒ [tex]e^{(-\lambda\times 4)} = 0.3[/tex]
∵ [tex]\lambda = 0.300993[/tex]
Now,
⇒ [tex]f(x) = \lambda e^{-\lambda x}[/tex]
By putting the value, we get
[tex]=0.300993e^{-0.300993x}[/tex]
A civil engineer is analyzing the compressive strength of concrete. Compressive strength is normally distributed with A random sample of 12 sample specimens has a mean compressive strength of psi. Round your answers to 1 decimal place. (a) Calculate the 95% two-sided confidence interval on the true mean compressive strength of concrete. Enter your answer; 95% confidence interval, lower bound Enter your answer; 95% confidence interval, upper bound (b) Calculate the 99% two-sided confidence interval on the true mean compressive strength of concrete.
Answer:
95%: (3278.354 ; 3270.083)
99% : (3221.646 ; 3278.354)
Step-by-step explanation:
Given :
Sample size, n = 12
Mean, xbar = 3250
Sample standard deviation = √1000
The 95% confidence interval :
Mean ± Margin of error
Margin of Error = Tcritical * s/√n
Tcritical at 0.05, df=12-1 = 11 ;
Tcritical at 95% = 2.20
Hence,
Margin of Error = (2.20 * √1000/√12) = 20.083
Confidence interval : 3250 ± 20.083
Lower boundary = 3250 - 20.083 = 3229.917
Upper boundary = 3250 + 20.083 = 3270.083
2.)
The 99% confidence interval :
Mean ± Margin of error
Margin of Error = Tcritical * s/√n
Tcritical at 0.01, df=12-1 = 11 ;
Tcritical at 99% = 3.106
Hence,
Margin of Error = (3.106 * √1000/√12) = 28.354
Confidence interval : 3250 ± 28.354
Lower boundary = 3250 - 28.354 = 3221.646
Upper boundary = 3250 + 28.354 = 3278.354
Can someone help me with this question an also the rest of my school work?
Answer:
I think this one is B
Step-by-step explanation:
posters n tees sold 486 items yesterday; one-third of these were t-shirts.how many t-shirts sold? how many posters?
Answer:
162 t-shirts, 324 posters
Step-by-step explanation:
Assuming they only sold t-shirts and posters, you can find the amount of t-shirts sold by dividing 486 by 3, or multiplying it by 1/3. This equals 162. This is because one third were t-shirts. To find the rest you just subtract 162 from the total of 486, or multiply 162 by 2. (since you already know the amount of 1/3, 2/3 is double that.)
Part 1: Joe and Hope were both asked to factor the following polynomial completely. Is one of them correct? Both of them? Neither of them? Explain what each of them did was correct and/or incorrect.
Part 2:
Find all the values of k so the the quadratic expression factors into two binomials. Explain the process used to find the values.
3x^2 + kx - 8
If we simplify, both Joe and Hope factored the polynomial correctly but Joe didn't complete it fully.
The first binomial can be further factored:
8x + 12 = 4(2x + 3)Part 2The quadratic expression needs to have two roots in order to be factored as two binomials.
The discriminant must be positive or zero:
D = b² - 4ac ≥ 0We have a = 3, b = k, c = -8
So we get following inequality:
k² - 4*3*(-8) ≥ 0k² + 96 ≥ 0Since k² is positive for any value of k, the solution is any value of k:
k ∈ RHope this attachment helps you.
5t/4y=3b/4c (solve for y)
I also need to know the steps.
thanks.
Answer:
[tex]y = \frac{5ct}{3b}[/tex]
Step-by-step explanation:
[tex]\frac{5t}{4y} =\frac{3b}{4c}[/tex]
1. start by multiplying y to both sides:
y × [tex]\frac{5t}{4y} =\frac{3b}{4c}[/tex] × y
[tex]\frac{5t}{4} =\frac{3b}{4c}y[/tex]
2. divide both sides by [tex]\frac{3b}{4c}[/tex]
[tex]\frac{5t}{4}/\frac{3b}{4c} =\frac{3b}{4c}y/\frac{3b}{4c}[/tex]
[tex]y = \frac{5ct}{3b}[/tex]
what is the answer to 10% of 900
Answer:
90 cause 90 times 10 is 900 and 10% times 10 is 100%
Step-by-step explanation:
Answer: 90
Step-by-step explanation: 900 × .10 = 90
Pls answer
Subtract -37 from -53
Answer:
-37 subtract -53
-53 subtract -37 = -16
Step-by-step explanation:
Answer:
The answer is 16
Step-by-step explanation:
-37-(-53) = -37 + 53
You can flip it to 53 - 37 which equals 16.
Hope this helps! :)
*Heads up you can also search this up* ^^
the average of two number is xy.if one number is x the other i
Answer:
z = (2xy-x)
Step-by-step explanation:
Let the first number be x and the other number is z.
According to question,
The average of two number is xy i.e.
[tex]\dfrac{x+z}{2}=xy\\\\x+z=2xy\\\\z=2xy-x[/tex]
So, the value of z is (2xy-x) i.e. the other number is (2xy-x).
Use Cramer's Rule to solve (if possible) the system of linear equations.
x1 + 2x2 =8
- x1 + x2 = 1
Required:
Find the coefficient matrix.
Answer:
x1 = 2
x2 = 3
Step-by-step explanation:
[tex]x_1=\frac{D_{x1}}{D}\\\\x_2=\frac{D_{x2}}{D}[/tex]
Here D is the coefficient matrix.
Hence
[tex]x_1=\frac{6}{3}\\x_1=2[/tex]
&
[tex]x_2=\frac{9}{3}\\x_2=3[/tex]
in the diagram below, BD is parallel to XY. what is the value of y?
a. 70
b. 130
c. 110
d. 20
I can't see the diagram sorry.
Step-by-step explanation:
Is there supposed to be a picture attached?
Find the time required for an investment of 5000 dollars to grow to 8600 dollars at an interest rate of 7.5 percent per year, compounded quarterly.
Answer:
about 7.3 years
Step-by-step explanation:
[tex]8600=5000(1+\frac{.075}{4})^{4*t}\\1.72=(1.01875)^{4t}\\log_{1.01875}1.72=4t\\29.19428479=4t\\t=7.298571198[/tex]
Answer:
The answer is t=7.3
Find the measure of of RA.
Answer:
RA = 24
Step-by-step explanation:
Since the triangle is isosceles ( 2 equal sides ) , then LU is a perpendicular bisector , so
AU = RU , that is
4r = 18 - 2r ( add 2r to both sides )
6r = 18 ( divide both sides by 6 )
r = 3
Then
RA = 18 - 2r + 4r = 18 + 2r = 18 + 2(3) = 18 + 6 = 24
The breaking strengths of cables produced by a certain manufacturer have a mean, , of pounds, and a standard deviation of pounds. It is claimed that an improvement in the manufacturing process has increased the mean breaking strength. To evaluate this claim, newly manufactured cables are randomly chosen and tested, and their mean breaking strength is found to be pounds. Assume that the population is normally distributed. Can we support, at the level of significance, the claim that the mean breaking strength has increased
The question is incomplete. The complete question is :
The breaking strengths of cables produced by a certain manufacturer have a mean of 1900 pounds, and a standard deviation of 65 pounds. It is claimed that an improvement in the manufacturing process has increased the mean breaking strength. To evaluate this claim, 150 newly manufactured cables are randomly chosen and tested, and their mean breaking strength is found to be 1902 pounds. Assume that the population is normally distributed. Can we support, at the 0.01 level of significance, the claim that the mean breaking strength has increased?
Solution :
Given data :
Mean, μ = 1900
Standard deviation, σ = 65
Sample size, n = 150
Sample mean, [tex]$\overline x$[/tex] = 1902
Level of significance = 0.01
The hypothesis are :
[tex]$H_0 : \mu = 1900$[/tex]
[tex]$H_1 : \mu > 1900$[/tex]
Test statics :
We use the z test as the sample size is large and we know the population standard deviation.
[tex]$z=\frac{\overline x - \mu}{\sigma / \sqrt{n}}$[/tex]
[tex]$z=\frac{1902-1900}{65 / \sqrt{150}}$[/tex]
[tex]$z=\frac{2}{5.30723}$[/tex]
[tex]$z=0.38$[/tex]
Finding the p-value:
P-value = P(Z > z)
= P(Z > 0.38)
= 1 - P(Z < 0.38)
From the z table. we get
P(Z < 0.38) = 0.6480
Therefore,
P-value = 1 - P(Z < 0.38)
= 1 - 0.6480
= 0.3520
Decision :
If the p value is less than 0.01, then we reject the [tex]H_0[/tex], otherwise we fail to reject [tex]H_0[/tex].
Since the value of p = 0.3520 > 0.01, the level of significance, then we fail to reject [tex]H_0[/tex].
Conclusion :
At a significance level of 0.01, we have no sufficient evidence to support that the mean breaking strength has increased.
Find the area of the surface generated when the given curve is revolved about the y-axis. The part of the curve y=4x-1 between the points (1, 3) and (4, 15)
Answer:
Step-by-step explanation:
Let take a look at the given function y = 4x - 1 whose point is located between (1,3) and (4,15) on the graph.
Here, the function of y is non-negative. Now, expressing y in terms of x in y = 4x- 1
4x = y + 1
[tex]x = \dfrac{y+1}{4}[/tex]
[tex]x = \dfrac{1}{4}y + \dfrac{1}{4}[/tex]
By integration, the required surface area in the revolve is:
[tex]S = \int^{15}_{ 3} 2 \pi g (y) \sqrt{1+g'(y^2) \ dy }[/tex]
where;
g(y) = [tex]x = \dfrac{1}{4}y + \dfrac{1}{4}[/tex]
∴
[tex]S = \int^{15}_{ 3} 2 \pi \Big( \dfrac{1}{4}y + \dfrac{1}{4}\Big) \sqrt{1+\Bigg(\Big( \dfrac{1}{4}y + \dfrac{1}{4}\Big)'\Bigg)^2 \ dy }[/tex]
[tex]S = \dfrac{1}{2} \pi \int^{15}_{ 3} (y+1) \sqrt{1+\Bigg(\Big( \dfrac{1}{4}\Big ) \Bigg)^2 \ dy } \\ \\ \\ S = \dfrac{1}{2} \pi \int^{15}_{ 3} (y+1) \dfrac{\sqrt{17}}{4} \ dy[/tex]
[tex]S = \dfrac{\sqrt{17}}{8} \pi \int^{15}_{ 3} (y+1) \ dy[/tex]
[tex]S = \dfrac{\sqrt{17} \pi}{8} (\dfrac{1}{2}(y+1)^2)\Big|^{15}_{3} \\ \\ S = \dfrac{\sqrt{17} \pi}{8} (\dfrac{1}{2}(15+1)^2-\dfrac{1}{2}(3+1)^2 ) \\ \\ S = \dfrac{\sqrt{17} \pi}{8} *120 \\ \\\mathbf{ S = 15 \sqrt{17}x}[/tex]
Choose the correct answers for (a) the total installment price, (b) the carrying charges, and (c) the number of months needed to save money at the monthly rate to buy the item for its cash price.
A bunk bed with a cash price of $1,998, at $143 per month for 15 months
Answer:
$2,145 ; $147 ; 14 months
Step-by-step explanation:
Given that :
The cash price, that is, the amount that would be paid if customer is to pay the entire amount item is worth at once = $1998
Monthly payment = $143
Period = 15 months
The total installment price ; total amount paid on a monthly pay for 15 months :
(monthly payment * period)
($143 * 15)
= $2,145
The carrying charge :
Installment pay - Cash amount
$(2,145 - 1,998)
= $147
The number of month needed to save at Monthly rate to buy item at it's cash price :
Cash price / monthly payment
$1998 / $143
= 13.97
= 14 months
-3/8 divided by -1/4
Flip the -1/4, cross deduct and should get 3/2
Answer:
It might be 3/2 or 1 and 1/2.
12x + 1 - 2(y + 2) = 12x - ______ - 2y
Answer:
-3
Step-by-step explanation:
12x + 1 - 2(y + 2)
=> 12x + 1 - 2y - 4
=> 12x - 3 - 2y
Answer:
-3
Step-by-step explanation:
12x+1-2y-4
12x+1-2y-4
12x-2y-3
HELP HELP QUICK QUICK
Answer:
multiplication by -1 will reflect over the x-axis
multiplication by a positive number will "scale" or "stretch" the function
Step-by-step explanation:
Lisa bought a house The value of the house increased by 1.5% each year for 2 years. At the end of 2 years, the value of the house was £123,627. Work out the value of the house when Lisa bought it.
Answer:
$370,881
Step-by-step explanation:
firstly we we multiply 1,5% by 2yrs. the answer we get is 3,0%. we then multiply 3 % by $123,627 and get $370,881
If Lisa bought a house The value of the house increased by 1.5% each year for 2 years. The value of the house was £123,627. The initial amount of the house is 95120.7.
What is Percentage?Percentage, a relative value indicating hundredth parts of any quantity.
Given,
Lisa bought a house The value of the house increased by 1.5% each year for 2 years
By the end of 2 years, the value of the house was £123,627.
A=P(1+rt)
A is the final amount,
r is rate of interest
t is the time
P is principle amount.
123,627=P(1+1.5/100 (2))
123657=P(1+0.15(2))
123657=P(1+0.3)
123657=1.3P
Divide both sides by 1.3
P=95120.7
The initial amount of the house when Lisa bought is 95120.7
To learn more on Percentage click:
https://brainly.com/question/28269290
#SPJ2
Decide if each answer will be less than or greater than the original number. Drag each to the correct category
250% of 18
35% of 300
62% of 182
300% of 250
89% of 525
120% of 72
That's a question about percentage.
Let's imagine that we want to know how much is 90% of 200. To do this calculation, we should multiply 200 by 90 and then divide the result by 100. We do that because 90% is the same thing that [tex]\frac{90}{100} =0,9[/tex]. So, 90% of 200 is equal to:
[tex]\frac{200\cdot90}{100} =\\\\\frac{18000}{100} =\\\\180[/tex]
Now, imagine that you would like to know how much is 100% of 999. First, we multiply 999 by 100 and divide the result by 999. So, 100% of a number is equal to itself. That's a very important information, because it's possible to understand this:
If the percentage is less than 100%, the result is less than original number.If the percentage is equal to 100%, the result is equal to the original number.If the percentage is greater than 100%, the result is greater than original number.Now, we can solve our problem! \o/
The options that the percentage is less than 100% are: 35% of 300, 62% of 182 and 89% of 525. Therefore, their answers will be less than the original number.
And, the option that the percentage is greater than 100% are: 250% of 18, 300% of 250 and 120% of 72. So, their answers will be greater than the original number.
On the image, you can see the answer in a table.
I hope I've helped. ^^
Enjoy your studies! \o/
A boat travels 8 miles north from point A to point B. Then it moves in the direction S 40°W and reaches point Finally, it turns S 40°E and returns to point A
The total distance covered by the boat is______miles
A. 14.95
B. 18.44
C. 20.04
D. 25.88
Answer:
B.18. 44 miles
Step-by-step explanation:
We are given that
Distance between A and B=8 miles
Angle B=Angle BCQ=40 degree (Alternate interior angles)
Angle ACB=180-Angle ACP-Angle BCQ
Angle ACB=180-40-40=100 degree
In triangle ABC
Angle A+ Angle B +Angle C=180 degree using sum of angles of triangle property
Substitute the values
[tex]\angle A+40+100=180[/tex]
[tex]\angle A+140=180[/tex]
[tex]\angle A=180-140[/tex]
[tex]\angle A=40[/tex] degree
Angle A=Angle B
When two angles are equal of a triangle then the triangle is isosceles triangle.
Therefore, triangle ABC is an isosceles triangle.
[tex]\implies BC=AC [/tex]
Now, Sine law
[tex]\frac{a}{sin A}=\frac{b}{sin B}=\frac{c}{sin C}[/tex]
Using the sine law
[tex]\frac{BC}{sin 40}=\frac{AB}{sin 100}[/tex]
[tex]\frac{BC}{sin 40}=\frac{8}{sin 100}[/tex]
[tex]BC=\frac{8\times sin40}{sin 100}[/tex]
BC=5.22
AC=BC=5.22 miles
Now, total distance covered by the boat=AB+BC+AC
Total distance covered by the boat=8+5.22+5.22=18.44 miles
Hence, option B is correct.
Which law would you use to simplify the expression
(P/q)^3?
power of a power
power of a quotient
quotient of powers
power of a product
Answer: Power of a quotient
Step-by-step explanation:
The power of quotient basically is:
[tex](\frac{P}{q})^{3} =\frac{P^3}{q^3}[/tex]
Please HELP!
How many pairs (A, B) are there where A and B are subsets of {1, 2, 3, 4, 5, 6, 7, 8} and A ∩ B has exactly two elements?
Answer:
There are 256 pairs in all.
Please help solve and explain this thank you
Answer:
hi
Step-by-step explanation:
If [infinity]∑n=0cn9n is convergent, does it follow that the following series are convergent? (a) [infinity]∑n=0cn(−3)n
Given: The series ∑cₙ[tex]9^n[/tex] is convergent
To find: The series ∑cₙ[tex](-3)^n[/tex] is convergent or not.
Solution: If the radius of convergence R the we can conclude that R≥4
So, the series will converge as -3<9.
Use the definition of a Taylor series to find the first four nonzero terms of the series for f(x) centered at the given value of a. (Enter your answers as a comma-separated list.)
f(x) = 7/(1+x), a = 2
Find the Maclaurin series for f(x) using the definition of a Maclaurin series. [Assume that f has a power series expansion. Do not show that Rn(x) → 0.]
f(x) = e−5x
f(x)=
[infinity]
n = 0
=
Find the associated radius of convergence R.
R =
Answer:
A) [ 7/3, (-7/9)(x/2), 7/27(x-2)^2, (-7/81)(x-2)^3 ]
B) attached below
Step-by-step explanation:
A) Using the definition of a Taylor series
The first four nonzero terms of the series for f(x) = 7/ (1 +x), a = 2
= [ 7/3, (-7/9)(x/2), 7/27(x-2)^2, (-7/81)(x-2)^3 ]
attached below is the detailed solution
B) Finding Maclaurin series for f(x)
f(x) = e^-5x
attached below
Associated radius of convergence = ∞ ( infinity )
-3xy^2+5xy^2
Operations with polynomials
9514 1404 393
Answer:
2xy^2
Step-by-step explanation:
The terms are "like" so can be combined. It might be helpful to think of this as an application of the distributive property.
-3xy^2 +5xy^2 = (-3 +5)xy^2 = 2xy^2
What value of x will make the equation true?
Answer:
5
Step-by-step explanation:
When a square root of an expression is multiplied by itself, the result is that expression
5=x
I NEED HELP ILL MARK!!!
Answer:
c) tan
Step-by-step explanation:
For the 63-deg angle, YZ is the opposite leg. The unknown side, AY, is the adjacent leg. The trigonometric ratio that relates the opposite and adjacent legs is the tangent.
Answer: c) tan