This confidence interval suggests that we are 90% confident that the population mean lies between $273 and $658.
This confidence interval provides us with an estimate of the population mean with 90% confidence. This confidence interval suggests that we are 90% confident that the population mean lies between $273 and In other words, we can be 90% sure that the population mean falls within this range. This confidence interval does not tell us the actual population mean, but it provides us with an estimate of where the population mean is likely to lie. Furthermore, it also provides us with an indication of the degree of uncertainty associated with our estimate.
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For which function i the average rate of change over the interval 1 < x < 5 greater than the average rate of change over the ame interval for the function g(x) = 1. 8x2?
Option D is correct the answer. The average rate of change over the interval 1 < x < 5 is greater than the average rate of change over the same interval for the function g(x) = 1. 8x2 is k(x) = 2x^2
The average rate of change:
Given a function y, the average rate of change S of y=f(x) in an interval (xs,xf) will be given by the following equation:
[tex]S=\frac{f(xf)-f(xo)}{xf-xo}[/tex]
In this problem, we have that:
Interval (1,5), so xf=5,xo=1
Then
[tex]S=\frac{f(5)-f(1)}{4}[/tex]
All options are compared to g(x).
[tex]g(x)=1.8x^{2}[/tex]
g(5) = 1.8*(5)^2 = 45
g(1) = 1.8*(1)^2 = 1.8
[tex]S=\frac{45-1.8}{4} =10.8[/tex]
A.=f(x) = x^2
f(5) = 5^2 = 25
f(1) = 1^2 = 1
[tex]S=\frac{25-1}{4} =6.25[/tex]
Smaller than 10.8, so this is not the answer.
B.=g(x) = 1.2x^2
g(5) = 1.2*(5)^2 = 30
g(1) = 1.2*(1)^2 = 1.2
[tex]S=\frac{30-1.2}{4} =7.2[/tex]
Smaller than 10.8, so this is not the answer.
C.=h(x) = 1.5x^2
h(5) = 1.5*(5)^2 = 37.5
h(1) = 1.5*(1)^2 = 1.5
[tex]S=\frac{37.5-1.5}{4}= 9[/tex]
Smaller than 10.8, so this is not the answer.
D.=k(x) = 2x^2
k(5) = 2*(5)^2 = 50
k(1) = 2*(1)^2 = 2
[tex]S=\frac{50-2}{4} =12[/tex]
Greater than 10.8, this is the answer.
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Can someone please help me with this assignment? I will mark your answer brainliest! :)
2[(x+2y)-4(6x+3y)+(4x+3y)]
Answer:
-38x - 14y
Step-by-step explanation:
2[x+2y - 24x - 12y + 4x + 3y]
2 [ -19x -7y]
- 38x - 14y
Sam types a constant number of words per minute.
He takes 8 minutes to type a report of 416 words.
How long does it take him to type an essay of 1534 words?
Give your answer in minutes and seconds?
Answer:
It would take Sam 29 minutes and 30 seconds
Whats the common denominator to find equivalent fractions for 2/3 and 1/6.
The common denominator of the fractions 2/3 and 1/6 will be 6.
What is the lowest common multiple?The lowest common multiple is the smallest multiple which is common between any two numbers.
It means we can divide both numbers by that and that is the smallest number by which both dived.
As per the given fractions 2/3 and 1/6.
Multiply 2 in numerator and denominator in 2/3.
2/3 x 2/2 = 4/6
Now denominator is the same thus common denominator is 6.
Hence "6 will be the common denominator for the fractions 2/3 and 1/6".
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Daliyah is given one point on a line as (3,−1) and the slope of the line as −5. What is the y-intercept of the line?
Answer: The y-intercept is 14
Step-by-step explanation:
The slope intercept is y=mx+b
since we already have the slope, we can write this as
y=-5x+b
substitute the points of (3,-1) into the equation and solve for b
-1=-5(3)+b
-1=-15+b
b=14
The y-intercept is 14
The y-intercept of the line is 14.
What is an equation of a line?The equation of a line is given by:
y = mx + c
where m is the slope of the line and c is the y-intercept.
Example:
The slope of the line y = 2x + 3 is 2.
The slope of a line that passes through (1, 2) and (2, 3) is 1.
We have,
Slope = -5
The line passes through the point (3, -1).
The equation of the line is y = mx + c.
y = -5x + c
(3, -1) = (x, y)
-1 = -5 x 3 + c
-1 = -15 + c
-1 + 15 = c
c = 14
Thus,
The y-intercept is 14.
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I need help with question one, who would you find the missing side length
similar triangles have a ratio and in this case the ratio is 1:2 i hope you understand
Rationalise the denominator 1/5-root 2
Answer:
the rationalized form of the denominator 1/(5^(1/2)-2) is (x+2)/((x-2)(x-1)(x+1)).
Step-by-step explanation:
Correctly me if im wrong. To rationalize the denominator of the fraction 1/(5^(1/2)-2), we can use the conjugate of the denominator. The conjugate of a+b is a-b, so the conjugate of 5^(1/2)-2 is 5^(1/2)+2. We can then multiply the numerator and denominator of the fraction by the conjugate to obtain:
1/(5^(1/2)-2) * (5^(1/2)+2)/(5^(1/2)+2)
= (1*(5^(1/2)+2)) / ((5^(1/2)-2)*(5^(1/2)+2))
= (5^(1/2)+2) / (5^2 - 2*5^(1/2) - 4)
Notice that we can further simplify this expression by substituting 5^(1/2) with x and expanding the denominator:
(5^(1/2)+2) / (5^2 - 2*5^(1/2) - 4)
= (x+2) / (x^2 - 2x - 4)
= (x+2) / (x-2)(x+2)
The denominator of this expression can be further simplified by factoring out x-2, which gives us:
(x+2) / (x-2)(x+2)
= (x+2) / (x-2)(x-2 + 4)
= (x+2) / (x-2)(x^2 - 2x + 4 - 4)
= (x+2) / (x-2)(x^2 - 2x)
= (x+2) / (x-2)((x-1)(x+1))
Finally, we can use the fact that x-1 and x+1 are factors of x^2-2x, which means that we can factor out x-1 and x+1 from the denominator to obtain the fully simplified expression:
(x+2) / (x-2)(x^2 - 2x)
= (x+2) / (x-2)(x-1)(x+1)
= (x+2) / ((x-2)(x-1)(x+1))
Therefore, the rationalized form of the denominator 1/(5^(1/2)-2) is (x+2)/((x-2)(x-1)(x+1)).
Find the equation of the line pictured.
Answer: y=-1/2x+4
Step-by-step explanation:
find the slope of the line given which would be-2/4 which simlifys down to 1/2 then add your b (y intercept) and that wold be 4.
1/2(40x-16)=32
What is the solution for x
Answer: x=2
Step-by-step explanation:
1/2(40x-16)=32
20x - 8 = 32
Add 8 on both sides
20x = 40
Divided both sides by 20
x = 2
slope: 3; y-intercept: -8
Two stores have the same item for the same price. • Store A offers successive discounts of 5% one week, 10% the next week, and 10% the third week. • Store B offers one discount of 25% the third week. Which offer results in the greater discount? Justify your answer. Show your work.
Answer:
Below
Step-by-step explanation:
10 % OFF means you pay 90% of price
x = original price
Store A : 5% off means price is .95x
then another 10% off would mean .9 * (.95x)
then another 10% off would mean .9 * ( .9 *(.95x)
this equals .7695 x
Store B 25% off means you pay 75%
price is then .75x
price of .75x at store B is < than .7695 x at store A
so B has greater discount
Answer:
Step-by-step explanation: To compare the discounts offered by Store A and Store B, we need to calculate the final price of the item after all discounts have been applied.
For Store A, the successive discounts of 5%, 10%, and 10% can be applied as follows:
The initial price of the item is reduced by 5%, resulting in a price of 0.95 * Price.
The price from step 1 is reduced by an additional 10%, resulting in a price of 0.9 * (0.95 * Price) = 0.855 * Price.
The price from step 2 is reduced by an additional 10%, resulting in a price of 0.9 * (0.855 * Price) = 0.7695 * Price.
For Store B, the single discount of 25% can be applied as follows:
The initial price of the item is reduced by 25%, resulting in a price of 0.75 * Price.
Comparing the final prices of the item at Store A and Store B, we can see that Store B offers a greater discount. The final price of the item at Store A is 0.7695 * Price, while the final price at Store B is 0.75 * Price. Since 0.75 is less than 0.7695, the final price at Store B is lower.
Therefore, Store B offers a greater discount on the item.
a conditional probability p(b|a) is equal to its marginal probability p(b) if
A conditional probability p(b | a) is equal to its marginal probability p(b) if A and B are independent.
The likelihood that any two events will occur is equal to the sum of the probabilities of each event separately, less the probability that the two occurrences will meet. However, if two occurrences are incompatible with one another, then there is a zero probability of the two events intersecting, therefore the likelihood that either one or the other will occur is equal to the sum of the two individual probabilities.
To calculate conditional probability, use the following formula:
p( b | a ) = p( a ∩ b )/ p(a)
It is known that if two events A and B are independent, then p(a ∩ b) = p (a) . p(b)
So, p(b | a) = [p (a) . p(b)]/p(a) = p(b)
Thus, it is concluded that a conditional probability p(b | a) is equal to its marginal probability p(b) if A and B are independent.
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17. Louis is offered an interest rate of 6.35%
for an investment with continuous
compounding. What is his equivalent rate
of interest with simple compounding?
[A] 1.23 or 12.3%
[B] 0.0593 or 5.93%
[C] 0.423 or 42.3%
ID] 0.0656 or 6.56%
[E] 0.0615 or 6.15%
The rate of interest for simple compounding if Louis is offered an interest rate of 6.35% for an investment with continuous compounding, is 0.0656 or 6.56%, so option D is correct.
What is interest?When the loan is given to you, then some amount is charged to you for the principal amount and that is called interest.
Given:
Louis is offered an interest rate of 6.35% for an investment with continuous compounding,
Here, P will be the same, the amount will be the same and the time period will be the same then,
The amount in simple compounding = The amount in continuous compounding
[tex]P(1 + r)^t = Pe^{rt}[/tex]
Here, r is the rate of interest for simple compounding,
[tex]1 + r = e^{0.0635}[/tex] (All same quantities get canceled)
r = 1.0656 - 1
r = 0.06556
r = 0.0656
r = 6.56%
Thus, the rate of interest for simple compounding is 6.56%.
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Domain: -4
BOOKMARK
Determine the domain and range for the following graph.
The domain and range for the following graph, is written below:
Domain (interval notation) : [-4,4)
Range (interval notation): [1,4)
Domain (inequality notation): -4 ≤ x < 4
Range (inequality notation): 1 ≤ x < 4
What is domain and range?The collection of values that can be put into a function's domain are called its parameters. The x values for a function like f(x) are contained in this collection (x). The collection of values that a function can take on is known as its range. Following the putting of the x value, the function outputs this sequence of values.
Utilizing graphs is a useful tool for determining the scope and range of functions. A graph's domain is the entire set of input values shown on the x-axis since the term "domain" refers to the set of potential input values. The various output values are displayed on the y-axis and make up the range.
Domain (interval notation) : [-4,4)
Range (interval notation): [1,4)
Domain (inequality notation): -4 ≤ x < 4
Range (inequality notation): 1 ≤ x < 4
As we know,
Domain is the x-values of a function
Range is the y values of a function
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Change from rectangular to cylindrical coordinates. (Let r ≥ 0 and 0 ≤ θ ≤ 2π.)
(a) (−7, 7, 7)
(√98, 7π /4,7) Incorrect:
(b) (−7, 7 3 , 1)
(14, π /3,1) Incorrect:
The cylindrical coordinates of (−7, 7, 7) are (√98, -π/4, 7). cylindrical coordinate (−7, 7 3 , 1) is (14, -π/3, 1).
We must switch from rectangular to cylindrical coordinates in the provided problem. (let r ≥ 0 and 0 ≤ θ ≤ 2π.)
A)(−7, 7, 7)
Given rectangular coordinates(x, y, z) =(−7, 7, 7)
The cylindrical coordinates are (r, θ, z)
As a result, we determine each value of r and θ separately.
r = √x²+y²
r = √(-7)²+(7)²
r = √49+49
r = √98
θ = tan⁻¹ (y/x)
θ =tan⁻¹ (7/-7)
θ =tan⁻¹ (-1)
θ = -π/4
So cylindrical coordinate = (r, θ, z) = (√98, -π/4, 7)
B) (-7,7√3,1)
Given rectangular coordinates(x, y, z) = (-1,1,1)
The cylindrical coordinates are (r, θ, z)
As a result, we determine each value of r and θ separately.
r = √x²+y²
r = √(-7)²(7√3)²
r = √49+147
r = √196
r = 14
θ = (y/x)
θ = (7√3/-7)
θ = (-√3)
θ = -π/3
So cylindrical coordinate = (r, θ, z) = (14, -π/3, 1)
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Find the distance between the two points rounding to the nearest tenth (if necessary).
(-3,-5) and (5,0)
What is the length of the mid-segment of a trapezoid whose vertices are I(-3, -5), J(8, -5), K(3, -9), and L(-3, -9)?
The length of the mid-segment of the given trapezoid will be 8.5.
What is quadrilateral?A quadrilateral is a geometrical 2d shape in which there are four sides and each side is connected and makes a close polygon.
In other meaning, a quadrilateral is a kind of polygon in which four sides for example rectangle, square, and parallelogram are quadrilateral.
As per the given vertices,
I(-3, -5), J(8, -5), K(3, -9), and L(-3, -9)
The trapezoid has been plotted below.
The length of LK = 3 - (-3) = 6 units.
Length IJ = 8 - (-3) = 11 units
The length of midsegment x = (11 + 6)/2 = 17/2 = 8.5
Hence "The supplied trapezoid's mid-segment will be 8.5 inches long.".
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if f(x) + x2[f(x)]5 = 34 and f(1) = 2, find f '(1).
if f(x) +[tex]x^{2}[/tex] [tex][ f(x) ]^{5}[/tex] = 34 and f(1) = 2, then f '(1) = - [tex]\frac{64}{81}[/tex]
f ′(x )'s indicates that it is derived from f (x). The second notation is dydx. The instantaneous rate at which y changes in relation to x is shown by this notation.
f(x) + [tex]x^{2}[/tex] [tex][ f(x) ]^{5}[/tex] = 34
differentiate with respect to x :
f' (x) + [tex]x^{2}[/tex] . 5 [tex][ f(x) ]^{4}[/tex] f'(x) + [tex][ f(x) ]^{5}[/tex] 2x = 0
putting x = 1
f' (1) + [tex]1^{2}[/tex] . 5 [tex]f(1)^{4}[/tex] f'(1) + [tex]f(1)^{5}[/tex] 2(1) = 0
f' (1) + 1.5 [tex](2)^{4}[/tex] f'(1) + [tex](2)^{5}[/tex] . 2 = 0
f' (1) + 80 f' (1) = - 64
81 f' (1) = - 64
f' (1) = - [tex]\frac{64}{81}[/tex]
thus , the f ' (1) is found.
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make a box-and-whisker plot of data 21,27,22,22,25,14,16,10
The minimum value, Q1, Median, Q3 and maximum value of the data are 10,15,21.5, 23.5 and 27 respectively. The box-and-whisker plot of data is attached
How to make a box-and-whisker plot of data?Given: 21,27,22,22,25,14,16,10
Arrange the data in ascending or descending order:
10,14,16,21,22,22,25,27
The minimum value = 10. The maximum value = 27
Find the median. The median is the value in the middle. The median values are 21 and 22. Thus:
10,14,16,21,22,22,25,27
Median (Q2) = (21+22)/2 = 21.5
Consider the values to the left of the median with one of the median numbers included (since we have two numbers in the middle): 10,14,16,21
Median = (14+16)/2 = 15
Thus, Q1 = 15
Also, consider the values to the right of the median with one of the median numbers included: 22,22,25,27
Meadian = (22+25)/2 = 23.5
Thus, Q3 = 23.5
To create a box and whiskers plot use Minimum value, Maximum value, Q1, Median(Q2) and Q3 (Check the attached image)
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Write the equation of the line that goes through the point (4, -7) and is perpendicular
to the line y + 6 = -:
⅔ (x - 1). Use the table to show your work, if needed, to determine
each form, and then give each form.
Point-Slope Form
Slope-Intercept Form
The point-slope form with a slope of 5/2 and a point of (4,-7) is 5x-2y=34.
What is line equation?
In its most basic form, an equation is a mathematical statement that indicates that two mathematical expressions are equal. 3x + 5 = 14, for example, is an equation in which 3x + 5 and 14 are two expressions separated by a 'equal' sign. A mathematical phrase with two equal sides separated by an equal sign is called an equation. An example of an equation is 4 + 6 = 10. Linear equations are classified into three types: point-slope, standard, and slope-intercept.
Here,
The slope of line perpendicular to the line y +6=-2/5(x-1)
m1=5/2
point=(4,-7)
y-y1=m(x-x1)
y+7=5/2(x-4)
2y+14=5x-20
5x-2y=34
The point-slope form for slope given as 5/2 and point as (4,-7) will be 5x-2y=34.
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A function is graphed below. On which
interval of x is the average rate of change
of the function the smallest?
X
3
7
21
39
65
Y
3
18
28
36
40
Answer:
The x-axis interval of 39 to 65 has the smallest rate of change.
Step-by-step explanation:
See the attached worksheet. The interval of x that results in the least change in y can be visually seen by plotting the points and drawing a curve. The curve begins to flatten as x increases. So the smallest rate of change is between the last two points, x = 39 to 65.
This can also be calculated by finding the change in y per a change in x. The table in the graph confirms the earlier observation. Dx and Dy represent the "delta," or difference, D, between the x (Dx) and y(Dy) values. The rate of change is calculated as Dy/Dx, or the change in y divided by the change in x. The results confirm that the 39 to 65 segment is the smallest, at 0.15.
What is the quotient?
Answer:
11/50
Step-by-step explanation:
=5x2+1= 11/5
=1/10×11×5
=11/50
If vertical angles are congruent, then two lines cut by a transversal are parallel.a. Trueb. False
The vertical angles are congruent, then the two lines cut by a transversal are parallel is False.
Option B is the correct answer.
What are corresponding angles?The angles that are in the same position on two parallel lines intersected by a transversal line on the parallel lines.
Corresponding angles are equal.
We have,
Vertical angles are congruent.
Vertical angles are pairs of opposite angles made by intersecting lines.
Thus,
For vertical lines to be congruent, we do not need two parallel lines.
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The gift hop at the Harbor Lighthoue ordered a hipment of 45 hirt with a pecial whale print. The hirt come in 5 different ize, and there are the ame number of hirt in each ize. How many hirt did the tore order in each ize? Write a diviion equation with that model the tory
equation will be the number of shirts ordered in each size. division equation with that model the theory 45 ÷ 5 = 9
The Harbor Lighthouse gift shop ordered a shipment of 45 shirts with a special whale print. This means that we need to divide 45 by 5, in order to find out how many shirts were ordered in each size. To do this, we can use a division equation.
In this equation, 45 represents the total number of shirts and 5 represents the number of sizes. The answer to this equation will be the number of shirts ordered in each size. When we divide 45 by 5, we get 9 as our answer. Therefore, the store ordered 9 shirts in each size.
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points b , c and d lie on a straight line
AC is perpendicular to BD
BC=6cm and BD=22cm
triangle ABC has an area of 42
calculate the size of angle x
Step-by-step explanation:
To Find : size of angle x
Solution:
Area of ΔABC = (1/2) * BC * AC
=> (1/2) * BC * AC = 42
=> (1/2) * 6 * AC = 42
=> AC = 14 cm
BD = BC + CD
=> 22 = 6 + CD
=> CD = 16 cm
Tan x = AC /CD
=> Tan x = 14/16
=> Tanx = 7/8
=> x = Tan⁻¹(7/8)
=> x = 41.186°
The size of the angle is - 41. 186°
Points b,c, and d lie in a straight line. AC is perpendicular to BDBC = 6 cm, BD = 22 cm. Triangle ABC has an area of 42cm². the size of the angle = xarea of triangle ABC = 1/2 * BC * AC
or, 1/2 *BC * AC = 42
or, 1/2 * 6 * AC = 42
or, 3 * AC = 42
divide both sides by 3,
AC = 14 cm
BD = BC + CD
or, 22 = 6 + CD
or, CD = 16 cm
tan x = [tex]\frac{AC}{CD}[/tex]
or, tan x = [tex]\frac{14}{16}[/tex]
or, tan x = [tex]\frac{7}{8}[/tex]
or , x = 41. 186°
∴ The size of the angle is - 41. 186°.
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What is 1/4 − (−1 1/2)? Write the answer as a mixed number in simplest form.
plsssssss help ill give 20 pnts
The answer as a mixed number in simplest form will be 1 3/4.
What is mean by Fraction?A fraction is a part of whole number, and a way to split up a number into equal parts. Or, A number which is expressed as a quotient is called fraction. It can be written as the form of p : q, which is equivalent to p / q.
Given that;
The expression is,
⇒ 1/4 - (- 1 1/2)
Now,
Since, The expression is,
⇒ 1/4 - (- 1 1/2)
Hence, Solve the expression as;
⇒ 1/4 - (- 1 1/2) = 1/4 + 3/2
= 1/4 + 6/4
= 7/4
= 1 3/4
Thus, The answer as a mixed number in simplest form will be 1 3/4.
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3x+8 = 3x+ does it have one solution no solution or infinite solutions? help needed extremely
Answer:
No solution
Step-by-step explanation:
There is no real value of [tex]x[/tex] you can substitute into this equation to make it true.
M. Jone wahed
2
5
of her laundry. Her on wahed
1
4
of it. Who wahed mot of the laundry? How much of the laundry till need to be wahed?
Solve thi on paper. Then check your work on Zearn. Who wahed mot of the laundry?
i greater than
o wahed mot of the laundry
Ms. Jones washed most of the laundry and the remaining laundry need to be washed is 7/20.
Converting the fraction to decimal to easily compare the amount of laundry washed.
Laundry washed by Ms. Jones = 2/5
Performing division
Laundry washed by Ms. Jones = 0.4
Laundry washed by her son = 1/4
Performing division
Laundry washed by her son = 0.25
0.4 is greater than 0.25, hence, Ms. Jones washed more laundry.
They washed the laundry in fractions. So, the total laundry can be taken as 1.
Total laundry washed = 0.4 + 0.25
Total laundry washed = 0.65
Remaining laundry = 1 - 0.65
Performing subtraction
Remaining laundry = 0.35
Converting into fraction = 35/100
Remaining laundry in fraction = 7/20
Thus, Ms. Jones washed more laundry and 7/20 is remaining.
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The complete question is -
Ms. Jones washed 2/5 of her laundry. Her son washed 1/4 of it. How much of the laundry still needs to be washed?
Question 2
Matilda needs at least $112 to buy a new dress. She has already saved $40. She earns $9 an'hour babysitting. What is the solution of the
inequality that determines how many hours she will need to babysit to buy the dress?
Let x represent the number of hours Matilda babysits.
Answer: x ≥ 8
Step-by-step explanation:
We know that our inequality must be greater than or equal to $112 because she needs at least $112 to buy the new dress. This is the first part of our inequality.
Next, we see that she already has $40 and will earn $9 an hour babysitting, if x is the number of hours. $9 an hour can become 9x, then we will add the $40 she already has for 9x + 40 as the second part of our inequality.
This complete inequality is:
9x + 40 ≥ 112
Now, we can solve by isolating the variable x with inverse operations.
9x + 40 ≥ 112
9x ≥ 72
x ≥ 8
Matilda needs to babysit at least 8 hours to afford the new dress.