Answer:
z=0
50%
Step-by-step explanation:
Which expression is equivalent to 6x3 + 3y2 – 5x3 + 2y2?
Answer:
The answer is c because6X^3 minus 5X^3 is just X^3 and 3Y^2 plus 2Y^2 is 5Y^2.
The survey included a random sample of 640 western residents and 540 northeastern residents. 39% of the western residents and 51% of the northeastern residents reported that they were completely satisfied with their local telephone service. Find the 99% confidence interval for the difference in two proportions
Answer:
The 99% confidence interval for the difference in two proportions is (0.0456, 0.1944).
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Western residents:
39% out of 640, so:
[tex]p_1 = 0.39[/tex]
[tex]s_1 = \sqrt{\frac{0.39*0.61}{640}} = 0.0193[/tex]
Eastern residents:
51% out of 540, so:
[tex]p_2 = 0.51[/tex]
[tex]s_2 = \sqrt{\frac{0.51*0.49}{540}} = 0.0215[/tex]
Distribution of the difference:
[tex]p = p_2 - p_1 = 0.51 - 0.39 = 0.12[/tex]
[tex]s = \sqrt{s_2^2+s_1^2} = \sqrt{0.0215^2+0.0193^2} = 0.0289[/tex]
Confidence interval:
[tex]p \pm zs[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower bound of the interval is:
[tex]p - zs = 0.12 - 2.575*0.0289 = 0.0456[/tex]
The upper bound of the interval is:
[tex]p + zs = 0.12 + 2.575*0.0289 = 0.1944[/tex]
The 99% confidence interval for the difference in two proportions is (0.0456, 0.1944).
If x+y=
= 12 and x = 2y, then x =
O
2
06
08
10
Answer:
2y + y = 12
3y = 12
y = 4
now , x = 2y
x = 2 ( 4 )
x = 8
hope that helps ✌
Compute the probability of the event E1 that Bob wins in a duel against Eve alone, assuming he shoots first. (Hint: Let x be the probability Bob wins in a duel against Eve alone, assuming he fires first. If Bob misses his first shot and then Eve misses her first shot, what is the probability Bob wins in terms of x
Answer: Hello your question is incomplete attached below is the missing
n ( 1 + n )
Step-by-step explanation:
P( Bob hits target ) = 1/3
P( Eve hits target ) = 2/3
P( Carol hits target ) = 1
Compute the P that Bob wins in a duel against Eve alone
P(Bob hits the target in first shot ) = n = 1/3
P(Bob hits the target in second shot ) = n^2 = ( 1/3 * 1/3 ) = 1/9
hence the probability of Bob winning( i.e. P( Bob wins Event E1 ) = n + n^2 = n ( 1 + n )
A circle has a radius of 7ft. Find the radian measure of the central angle θ that intercepts an arc of length 6ft.
Answer:
49.09°
Step-by-step explanation:
c = circumference = 2×π×r
= 2× 22/7 ×7 = 44 ft
θ = 6/c × 360°
= 6/44 × 360° = 49.09°
Enter the ratio as a fraction in lowest terms
6 minutes to 30 minutes.
6 minutes / 30 minutes
Divide the top and bottom by 6.
1 minute / 5 minutes
Fraction in lowest terms: 1/5
Hope this helps!
What number increased by 30% is 34.5
Answer:
44.85
Step-by-step explanation:
There are two ways to do it, you can either multiply 0.3 by 34.5 and then add it to 34.5 to get 44.85, or you can add the 30% to 100% and get 1.3 which you multiply by 34.5 and that gets you 44.85
Mr.Peter earned $25 per week how much does he earned in a year
Answer: Approximately $1,300
Step-by-step explanation:
There is around 52 weeks in a normal year.
$25 · 52 = $1300
Answer:
1300
Step-by-step explanation:
There are 52 weeks in a year
52 * 25 = 1300
The population of a city increased from 23,400 to 27,800 between 2008 and 2012. Find the change of population per year if we assume the change was constant from 2008 to 2012.
Find the amount of the increase:
27800 - 23400 = 4,400
Find number of years: 2012 - 2008 = 4 years
Divide amount of change by number of years:
4,400 / 4 = 1,100 people per year.
8 ^ 3 −9⋅2÷3 can someone please help me quickly
Answer:
506
Step-by-step explanation:
8³-9×2÷3
= 512 - 9 × 2 ÷3
= 512 - 9 × ⅔
= 512 - 3 × 2
= 512 - 6
= 506
PEDMAS rule
P: Parentheses
E: Exponent
D: Division
M: Multiplication
A: Addition
S: Substraction
áp dụng quy tắc khai phương 1 tích hãy tính
Answer:
Please write out in english
Step-by-step explanation:
I cannot help unless you can translate.
Find the least whole number N so that 123+N is a perfect square.
21
12^2 = 144
144 - 123 = 21
11^2 = 121
12^2 = 144
Between these
Answered by Gauthmath must click thanks and mark brainliest
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
Plz help’
!
I’ll be giving extra points
because it's value will always be same
Answer:
This value doesn't depend on x or y
It'll be the same things always
Can someone check my answers if they are correct or incorrect? If it is incorrect, please let me know why it is incorrect please.
Which statement is true about the ratios of squares to
cicles in the tables? PLS HURRY!!!!
Answer:
show us a screenshot or image
or type it out, copy paste
Step-by-step explanation:
si 40/a = 35/7 entonces cual es el valor de a
Respuesta:
a = 8
Explicación paso a paso:
Para obtener el valor de a en la ecuación:
40 / a = 35/7
Cruzamos multiplicamos:
40 / a = 35/7
40 * 7 = 35 * a
280 = 35a
Dividir ambos lados por 35
280/35 = 35a / 35
8 = a
a = 8
Your car can go 2/7 of the way on 3/8 of a tank of gas how far can you go on the remaining gas?
A proportion that can be used is a/b=c/d
Answer:
10/21 of the distance
Step-by-step explanation:
2/7 distance
------------------
3/8 tank
The rest of the tank is 8/8 - 3/8 = 5/8
2/7 distance x
------------------ = ----------------------
3/8 tank 5/8 tank
Using cross products
2/7 * 5/8 = 3/8x
10/56 = 3/8x
Multiply each side by 8/3
10/56 * 8/3 = 3/8x * 8/3
10/3 * 8/56=x
10/3 * 1/7 =x
10/21 =x
10/21 of the distance
Ben consumes an energy drink that contains caffeine. After consuming the energy drink, the amount of caffeine in Ben's body decreases exponentially. The 10-hour decay factor for the number of mg of caffeine in Ben's body is 0.2722. What is the 5-hour growth/decay factor for the number of mg of caffeine in Ben's body
Answer:
The 5-hour decay factor for the number of mg of caffeine in Ben's body is of 0.1469.
Step-by-step explanation:
After consuming the energy drink, the amount of caffeine in Ben's body decreases exponentially.
This means that the amount of caffeine after t hours is given by:
[tex]A(t) = A(0)e^{-kt}[/tex]
In which A(0) is the initial amount and k is the decay rate, as a decimal.
The 10-hour decay factor for the number of mg of caffeine in Ben's body is 0.2722.
1 - 0.2722 = 0.7278, thus, [tex]A(10) = 0.7278A(0)[/tex]. We use this to find k.
[tex]A(t) = A(0)e^{-kt}[/tex]
[tex]0.7278A(0) = A(0)e^{-10k}[/tex]
[tex]e^{-10k} = 0.7278[/tex]
[tex]\ln{e^{-10k}} = \ln{0.7278}[/tex]
[tex]-10k = \ln{0.7278}[/tex]
[tex]k = -\frac{\ln{0.7278}}{10}[/tex]
[tex]k = 0.03177289938 [/tex]
Then
[tex]A(t) = A(0)e^{-0.03177289938t}[/tex]
What is the 5-hour growth/decay factor for the number of mg of caffeine in Ben's body?
We have to find find A(5), as a function of A(0). So
[tex]A(5) = A(0)e^{-0.03177289938*5}[/tex]
[tex]A(5) = 0.8531[/tex]
The decay factor is:
1 - 0.8531 = 0.1469
The 5-hour decay factor for the number of mg of caffeine in Ben's body is of 0.1469.
Melinda takes out a loan to purchase a car. The balance on her loan after x months is represented by the equation y = 10,000 – 250x and the value of the car after x months is represented by y = 8,000 – 50x. Which statement describes when Melinda’s loan will be equal to the value of the car?
After 10 months, the loan and value of the car will both be equal to $7,500.
After 12 months, the loan and value of the car will both be equal to $7,000.
After 14 months, the loan and value of the car will both be equal to $6,500.
After 16 months, the loan and value of the car will both be equal to $6,000.
Answer:
After 10 months, the loan and value of the car will both be equal to $7,500.
Step-by-step explanation:
Value of the loan after x months:
[tex]y_l = 10000 - 250x[/tex]
Value of the car after x months:
[tex]y_c = 8000 - 50x[/tex]
Which statement describes when Melinda’s loan will be equal to the value of the car?
They are equal when:
[tex]y_l = y_c[/tex]
So
[tex]10000 - 250x = 8000 - 50x[/tex]
[tex]200x = 2000[/tex]
[tex]x = \frac{2000}{200}[/tex]
[tex]x = 10[/tex]
Equal after 10 months:
Value of [tex]y(10) = 8000 - 50(10) = 7500[/tex]
Thus, the correct option is:
After 10 months, the loan and value of the car will both be equal to $7,500.
State whether the equations provided are true or false and why
Answer:
a) true
b) false
c) false
Step-by-step explanation:
remember: if a negative exponent is in the numerator, move the expression to the denominator and make the exponent positive and if a negative exponent is in the denominator, move the expression to the numerator and make the exponent positive
a explanation- 7a x 1/b^3 = 7a/b^3
b explanation- z^-5/12 = 1/12z^5
c explanation- 1/-7x^-1 = -7x
... please give brainliest if you can :)) ...
investing $12,000 in a savings account at 6% annual interest compounded monthly will result in approximately how much money after five years? use formula A 0 P(1 + r/m) ^mt
Answer:
$16186.20
Step-by-step explanation:
Assuming that P represents the initial amount, A represents the end amount, r represents the annual interest rate, m represents the amount of times compounded per year, and t represents the amount of years, we can write this as
A = P(1+r/m)^(mt)
Since 12,000 is invested, that is the initial amount. To find the interest rate as a decimal from a percent (as we need it in decimal form for this formula), we can divide the percent by 100 to get 6%/100 = 0.06 as our interest rate. Because there are 12 months in a year, the interest is compounded 12 times a year, and since it takes 5 years, t=5. Our formula is now
A = 12000 * (1+0.06/12)^(12 * 5)
A = 12000 * (1+0.06/12) ^(60)
A = 16186.20 rounded to the nearest cent
Solve.
x^2 - 9x + 3 = 0
x= or x=
Answer:
Step-by-step explanation:
x^2 - 9x + 3 = 0 is a quadratic whose coefficients are a = 1, b = -9 and c = 3.
Use the quadratic formula to solve it.
The discriminant, b^2 - 4ac, is 81 - 4(1)(3), or 81 - 12, or 69.
The roots are:
-b ± √(discriminant)
x = -------------------------------
2a
And these roots in this particular problem are:
-(-9) ± √69 9 ± √69
= ------------------------------- = ----------------
2(1) 2
-1/12 to the second power? Halp me plz
Answer:
1/144
Step-by-step explanation:
(-1/12)^2
(-1/12)*(-1/12)
1/144
Please help!!!
The figures to the right are similar. Compare the first figure to the second. Give the ratio of the perimeters and the ratio of the areas (integer or a simplified fraction)
Answer:
Perimeter: 3/4
Area: 9/16
Step-by-step explanation:
The ratio of the perimeters is equal to the ratio of the sides so:
18/24 = 3/4
Ratio of Area = (Ratio of Sides)^2
(3/4)^2 = 9/16
I wasn't sure about the answer so I used Gauthmath
please help.
find the missing side or angle and each problem .
If 15% of the customer's total is $22.05, then the customer's total is
Answer:
$147
Step-by-step explanation:
0.15x = $22.05
Divide both sides by 15
22.05/0.15 = $147
Find each question solutions.Please
Answer:
Dependent variable = Total daily cost
Independent variable = number of items manufactured
2500 ;
9750
Step-by-step explanation:
Given the cost function in. A manufacturing company :
C(x) = 7.25x + 2500 ; Where
C(x) = total daily cost
x = number of items manufactured
The Independent variable is the variable whose value causes a change in the measured variable, this is the number of items manufactured, and the variable which charges as the predictor variable charges is the dependent variable (Total daily cost).
2.)
C(0) ;
C(x) = 7.25x + 2500
Put x = 0
C(0) = 7.25(0) + 2500
Cost = 2500
This is the total daily cost even if no items are produced, this is probably the fixed cost of daily production.
3.)
C(1000)
C(x) = 7.25x + 2500
Put x = 1000
C(0) = 7.25(1000) + 2500
Cost = 7250 + 2500
Cost = 9750
This is the total cost including variable cost of producing 1000 items.
Can someone help me? I am struggling and I would be so happy if any of you helped me. Thank you for your help!
Answer:
Mean = 52
Standard Deviation = 13.64
Step-by-step explanation:
mean = 260/5
= 52
Standard Deviation = [tex]\sqrt{\frac{930}{5} }[/tex] = 13.64
I wasn't sure about my answer so used the Gauthmath app
How many square inches of sheet metal are used to make the vent transition shown? (The ends are open.)
Answer:
Area of the metal sheet required = 364 square inches
Step-by-step explanation:
Area of the metal sheet required = Surface area of the lateral sides of the vent transition
Since, lateral sides of the vent is in the shape of a trapezoid,
Therefore, surface area of the vent = 4(Surface area of one lateral side)
= [tex]4[\frac{1}{2}(b_1+b_2)h][/tex]
Here, [tex]b_1[/tex] and [tex]b_2[/tex] are two parallel sides and [tex]h[/tex] is the distance between these parallel sides.
Surface area of the vent = [tex]4[\frac{1}{2}(8+5)14][/tex]
= 364 square inches
Therefore, area of the metal sheet required = 364 square inches
