Answer:
a rational number is a number that can be written as a fraction
I hope this helps
A savings and loan association needs information concerning the checking account balances of its local customers. A random sample of 14 accounts was checked and yielded a mean balance of $664.14 and a standard deviation of $279.29. Find a 99% confidence interval for the true mean checking account balance for local customers.
Answer:
The 99% confidence interval for the true mean checking account balance for local customers is ($439.29, $888.99).
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 14 - 1 = 13
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 13 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995[/tex]. So we have T = 3.0123
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 3.0123\frac{279.29}{\sqrt{14}} = 224.85[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 664.14 - 224.85 = $439.29
The upper end of the interval is the sample mean added to M. So it is 664.14 + 224.85 = $888.99.
The 99% confidence interval for the true mean checking account balance for local customers is ($439.29, $888.99).
I need help with this
Answer:
C
Step-by-step explanation:
In the graph given, we can expect the x axis to be horizontal and the y axis to be vertical. This means that the arm span represents y and the height represents x.
Therefore, if a girl on her team is 63 inches tall, we can say that y=x+2, and since height is x, y = 63 + 2 = 65
Please Help!!! Whoever helps first and gets it correct gets Brainliest!
Answer:
Step-by-step explanation:
You have three data points. Equation of the line passing through (30,2), (45,2.75), and (60,3.50):
y = 0.5x + 0.5
It takes 0.5 hour to clean up.
A two-dimensional vector has an x-component of 10.3~\text{meters}10.3 meters and a y-component of 4.30~\text{meters}4.30 meters. Calculate the angle (in degrees) that this two-dimensional vector makes with the positive x-axis.
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Answer:
23°
Step-by-step explanation:
The angle a vector makes relative to the +x axis is found as ...
α = arctan(y/x) = arctan(4.30/10.3) ≈ 22.66°
The angle is about 23°.
__
Additional comment
This vector resides in the first quadrant, so no adjustment of the angle is needed. In other quadrants, 180° may need to be added or subtracted from the angle given by the arctan function to arrive at the correct value. (Some calculators and spreadsheets have an ATAN2(x, y) function that takes signs into account.)
a. A contest entrant has a 0.002 probability of winning $12,165. If this is the only prize and the fee is $35, then find the expected value of winning the contest. b. The probability of winning a lottery is 0.125. What is the probability of winning AT LEAST ONCE in twelve trials?
Answer:
The right answer is:
(a) -10.67
(b) 0.7986
Step-by-step explanation:
(a)
According to the question,
X P(X) X.P(X) X2.P(X)
12130 0.002 24.26 294274
-35 0.998 -34.93 1222.55
Now,
[tex]\Sigma x.P(x) = -10.67[/tex]
or,
[tex]\Sigma x^2.P(x) = 295496.35[/tex]
hence,
The mean will be:
[tex]\Sigma x.P(x) = -10.67[/tex]
(b)
According to the question,
n = 12
p = 0.125
q = 1 - p
= 0.875
Now,
⇒ [tex]P(X=x) = \binom{n}{x} p^x q^{n-x}[/tex]
By substituting the values, we get
⇒ [tex]P(X \geq 1)=1-(\binom{12}{0} 0.125^0. 0.875^{12-0})[/tex]
⇒ [tex]=1-(1 (0.125^0) (0.875^{12}))[/tex]
⇒ [tex]=1-(1(1.0)(0.2014))[/tex]
⇒ [tex]=1-(0.2014)[/tex]
⇒ [tex]=0.7986[/tex]
A study by researchers at a university addressed the question of whether the mean body temperature of an animal is 98 6°F Among other data, the researchers obtained the body temperatures of 109 healthy animals. Suppose you want to use those data to decide whether the mean body temperature of healthy animals is less than 98.6°F.
Required:
a. Determine the null hypothesis
b. Determine the alternative hypothesis
Answer:
H0 : μ ≥ 98.6
H1 : μ < 98.6
Step-by-step explanation:
The population mean temperature, μ = 98.6
The null hypothesis takes up the value of the population mean temperature as the initial truth ;
The alternative hypothesis on the other hand is aimed at using a sample size of 109 to establish if the mean temperature is less than the population mean temperature.
The hypothesis ;
Null hypothesis, H0 : μ ≥ 98.6
Alternative hypothesis ; H1 : μ < 98.6
Which of the following could be the equation of the graph shown below?
Answer:
According to the proposed interrogate, as well as the graph provided, the correct answers to such are identified as B. Y = -2x + 5 and C. 2x + y = 4.
Step-by-step explanation:
To evaluate such, a comprehension of linear Cartesian data is required:
Slope = rise/run. If there is a negative rise, the direction of the line is proportional to the left-hand side as it exponentially grows or augments in units.
Y-intercept: The peculiar point in which the linear data observed intersects the y-axis.
X-intercept: The peculiar point in which the linear data observed intersects the x-axis.
Since this is a negative linear, all negative slopes apply.
The interrogate states, “Check all that apply.” Thus, there may be more than one correct answer, shall such be disseminated.
A. Cannot be the answer as the line should have been a horizontal line contained within quadrants I and II on the Cartesian Plane.
B. Contains a negative slope, thus is disclosed as a correct answer.
C. This configuration is denoted in “Standard Form” or “General Form”. To convert this to “Slope-Intercept Form” the following must be executed mathematically:
2x + y = 4
Y = -2x + 4 <== Slope-Intercept Form (Contains a negative slope, thus considered a correct answer.
D. Likewise, this configuration is denoted in “Standard Form” or “General Form”. To convert this to “Slope-Intercept Form” the following must be executed mathematically:
X - y = 9
-y = -x + 9
Y = x - 9 <== Slope-Intercept Form (Cannot be considered as the correct answer, given the positive slope configuration, thus is marked out).
Thus far, as evaluated, the correct answers to the proposed interrogate, as according to the linear data provided in the Cartesian Plane is acknowledged, and henceforth disseminated, as B. Y = -2x + 5 and C. 2x + y = 4.
*I hope this helps.
How to divide 6,558 by 4 in long division
This is the solution to your question.
An appliance uses 120 W. If this appliance is on for 8 hours a day, how much CO2 will this produce in the month of April?
...
Calculate Energy Cost by Appliance
Multiply the device's wattage by the number of hours the appliance is used per day.Divide by 1000.Multiply by your kWh rate.hope it's helpful for you!!..pls give me brainlist !!....Find the length of AC
A. 377.19
B. 378.63
C. 2.89
D. 33.13
Answer:
AC = 377.19
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
tan theta = opp /adj
tan 5 = 33/AC
AC tan 5 = 33
AC = 33/ tan 5
AC = 377.19
Write out the first 5 terms of the following sequence:
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Answer:
2, 1, -1/2, -1/4, 1/8
Step-by-step explanation:
Use n = 1 through 4:
[tex]a_{1+1}=\dfrac{(-1)^{1+1}\cdot a_1}{2}\ \Rightarrow\ a_2=\dfrac{1\cdot2}{2}=1\\\\a_3=\dfrac{(-1)^3\cdot 1}{2}=-\dfrac{1}{2}\\\\a_4=\dfrac{(-1)^4\cdot(-\dfrac{1}{2})}{2}=-\dfrac{1}{4}\\\\a_5=\dfrac{(-1)^5\cdot(-\dfrac{1}{4})}{2}=\dfrac{1}{8}[/tex]
The first 5 terms are ...
2, 1, -1/2, -1/4, 1/8
PLEASE HELP. What are the coordinates of the terminal point for theta= 4pi/3
Answer:
D
Step-by-step explanation:
i simply used the unit circle
Identify a pattern in the given list of numbers. Then use this pattern to find the next number. (More than one pattern might exist, so it is possible that there is more than one correct answer.)
27,-9 ,3 ,-1 ,___
Work out giving ur answer as a mixed number
Answer:
6 11/12
Step-by-step explanation:
4 1/6 + 2 3/4
Get a common denominator of 12
4 1/6 *2/2 + 2 3/4 *3/3
4 2/12 + 2 9/12
6 11/12
The strength of the association rule is known as _____ and is calculated as the ratio of the confidence of an association rule to the benchmark confidence.
Answer:
Lift
Step-by-step explanation:
Finding patterned and relationship between large sets of data can be obtained using the association rule as it finds insights, relationships and trends within sets of data variables. Lift is a parmater of interest whichbus used when performing analysis on association between variables in datasets. The Lift is literally the ratio of confidence to expected confidence. Where, the confidence of association is divided by the expected confidence (benchmark confidence).
work out the surface area of this solid quarter cylinder in terms of pi. r 10cm.h 16
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Answer:
(320 +130π) cm²
Step-by-step explanation:
The perimeter of the base will be the sum of two radii and the arc length of a quarter circle:
P = 2r +r(π/2) = r(2+π/2)
For a radius of 10 cm, the perimeter of the base is ...
P = (10 cm)(2+π/2) = (20+5π) cm
The lateral area of the quarter-cylinder is the product of this perimeter and the height:
LA = Ph = ((20 +5π) cm)(16 cm) = (320 +80π) cm²
__
The total base area is the area of a half-circle of radius 10 cm, so is ...
BA = 1/2πr² = (1/2)π(10 cm)² = 50π cm²
The total surface area is the sum of the base area and the lateral area:
SA = BA +LA = (50π +(320 +80π)) cm² = (320 +130π) cm²
An experiment consists of tossing a pair of balanced, six-sided dice. (a) Use the combinatorial theorems to determine the number of sample points in the sample space S. 36 Correct: Your answer is correct. sample points (b) Find the probability that the sum of the numbers appearing on the dice is equal to 6. (Round your answer to four decimal places.)
Answer:
Sample space = 36
P(sum of 6) = 5/36
Step-by-step explanation:
Number of faces on a dice = 6
The sample space, for a toss of 2 dice ; (Number of faces)^number of dice
Sample space = 6^2 = 6*6 = 36
Sum of numbers appearing on the dice = 6
The sum of 6 from the roll of two dice has 5 different outcomes ; Hence, required outcome = 5
Total possible outcomes = sample space = 36
Probability, P = required outcome / Total possible outcomes
P = 5 / 36
Probabilities are used to determine the chances of events
The given parameters are:
[tex]n=6[/tex] --- the faces of a six-sided die
[tex]r = 2[/tex] -- the number of dice
(a) The number of sample points
This is calculated as:
[tex]Sample = n^r[/tex]
So, we have:
[tex]Sample = 6^2[/tex]
Evaluate the exponent
[tex]Sample = 36[/tex]
Hence, the number of sample points is 36
(b) The probability that the sum of 6
See attachment for the sample space of the sum of two dice.
From the sample space, there are 5 outcomes where the sum is 6.
So, the probability is:
[tex]Pr = \frac{5}{36}[/tex] --- where 36 represents the number of sample points
Divide 5 by 36
[tex]Pr = 0.1389[/tex]
Hence, the probability that the sum of the numbers appearing on the dice is equal to 6 is 0.1389
Read more about probabilities at:
https://brainly.com/question/10707698
For a certain company, the cost for producing x items is 40x+300 and the revenue for selling x items is 80x−0.5x2. The profit that the company makes is how much it takes in (revenue) minus how much it spends (cost). In economic models, one typically assumes that a company wants to maximize its profit, or at least wants to make a profit!
Part a: Set up an expression for the profit from producing and selling x items. We assume that the company sells all of the items that it produces. (Hint: it is a quadratic polynomial.)
Part b: Find two values of x that will create a profit of $300.
The field below accepts a list of numbers or formulas separated by semicolons (e.g. 2;4;6 or x+1;x−1). The order of the list does not matter. To enter a−−√, type sqrt(a).
Part c: Is it possible for the company to make a profit of $15,000?
Answer:
The profit is maximum when x = 40.
Step-by-step explanation:
Cost function, C = 40 x + 300
Revenue function, R = 80 x - 0.5 x^2
The profit function is
[tex]P = R - C\\\\P = 80 x - 0.5 x^2 - 40 x - 300\\\\P = - 0.5 x^2 + 40 x - 300\\\\\frac{dP}{dx} = - x + 40\\\\So, \frac{dP}{dx} = 0\\\\-x + 40 = 0 \\\\x = 40[/tex]
So, the profit is maximum when x = 40 .
Leo is running in a 5-kilometer race along a straight path. If he is at the midpoint of the path, how many kilometers does he have left to run?
Answer:
2.5 km left
The midpoint is half of 5, which is 2.5, so he'll still have 2.5 km left to complete
2(x-4) +3(2-x) +2x +7
Answer:
x+5
Step-by-step explanation:
Answer:
2x-8+6-3x +2x +7
= 2x -3x +2x -8+6+7
=4x-3x-8+13
= 1x+5
A pizza is to be cut into fifths. Each of these fifths is to be cut into thirds. What fraction of the pizza is each of the final pieces?
If f(x) = x³ - 2, find f(3)
Answer:
25
Step-by-step explanation:
Assuming the equation is f(x) = x³ - 2
Plug in 3 for x
f(3) = 3³-2
= 27-2
=25
Answer:
25!
I hope it's helpful
Evaluate the expression 3√64
Answer:
4
Step-by-step explanation:
We want the cubed root of 64
(64)^(1/3)
(4*4*4) ^ (1/3)
4
Unless this is 3 * sqrt(64)
then it would be
3 sqrt(8*8)
3 (8)
24
It takes Barry 912 hours to detail a car. If he worked 57 hours during the week, how many cars did he detail?
Answer:
He detailed 16 cars.
912/57=16
Step-by-step explanation:
michael has an average of 68% in his 3 papers but that is below the pass mark of 70%. what must be his least score in the fouth paper to enable him pass?
Answer:
His least score for him in the fourth paper has to be 76.
Step-by-step explanation:
Given that Michael has an average of 68% in his 3 papers but that is below the pass mark of 70%, to determine what must be his least score in the fouth paper to enable him pass the following calculation must be performed:
(70 x 4) - (68 x 3) = X
280 - 204 = X
76 = X
Therefore, his least score for him in the fourth paper has to be 76.
Work out the length x. 14 cm 7 cm Х
Answer:
If you want the area of something with the sides 14cm and 7cm then it would be 98 cm.
Step-by-step explanation:
Area = length * width
Area = 14 cm * 7 cm
Area = 98 cm
Verify if : (-30) x ( 13.+ (-3)] =[(-30) x 13] + [(-30) (-3)]
Dodi bicycles 14mph with no wind. Against the wind, Dodi bikes 10mi in the same time it takes to bike 20mi with the wind. What is the speed of the wind?
Answer:
4.67 mph
Step-by-step explanation:
Speed with no wind = 14 mph
Let wind speed = w mph
Thus;
Speed with wind = 14 + w
Speed against the wind = 14 - w
Now, we are told that against the wind he bikes 10 miles.
Thus, from; time = distance/speed, we have;
Time = 10/(14 - w)
Also, we are told he biked 20 miles with the wind. Thus;
Time = 20/(14 + w)
We are told the times he used in both cases are the same.
Thus;
10/(14 - w) = 20/(14 + w)
Divide both sides by 10 to get;
1/(14 - w) = 2/(14 + w)
Cross multiply to get:
1(14 + w) = 2(14 - w)
14 + w = 28 - 2w
w + 2w = 28 - 14
3w = 14
w = 14/3
w = 4.67 mph
1. The equation of a circle is x^2 + y^2 + 6x - 4y + 4 = 0. What are the center and the radius of the circle? Show ALLLLLL your work
Answer:
(2, -3) and r = 3.
Step-by-step explanation:
you can also plug this equation in desmos but I guess it's good to know how to do it also:
The equation of a circle is (x-h)^2 + (y-k)^2 = r^2
Now in order to make a perfect square on both sides, we need to do this:
First add 9 to both sides:
x^2 + 6x + 9 + y^2 -4y +4 = 9.
I purposely shifted it to show the perfect square created when you add 9 to both sides. Factor:
(x+3)^2 + y^2 - 4y + 4 = 9.
now the second bolded part is allso a perfect square. Factor:
(x+3)^2 + (y-2)^2 = 9
Based on the equation of a circle, the center must be at (2, -3) and the radius is the square root of 9 which is 3.
:)
the following 3 shapes are made up of square, circles, and semi circles. Find the Area and perimeter of the shaded area. Write your answer as a completely simplified exact value in terms of pi
Answer:
Perimeter = 18 + 9pi
Area = 81 - 20.25*pi
Step-by-step explanation:
Perimeter = 9 + 9 + 2(2 pi r)/2 The twos cancel out.
Perimeter = 18 + 9*pi
Area of the square = 9 * 9 = 81 cm^2
Area of the 2 semicircles = 2 * pi * r^2/2
r = d/2
d = 9
r = 9/2 = 4.5
Area of the 2 semicircles = 2 (pi * 4.5^2)/2
Area of the 2 semicircles = 20.25 pi
Area of the blue figure = 81 - 20.25 pi
