Suppose there is a strong positive correlation between a and b. Which of the
following must be true?
A. An increase in a causes b to decrease.
B. An increase in a causes bto increase.
C. When a increases, b tends to increase.
D. When a increases, b tends to decrease.
ANSWER ASAP WILL GIVE BRAINLIEST
Answers
Answer:
B.
Step-by-step explanation:
there is not much to explain.
a strong correlation means there is a direct connection.
so, a change in a causes immediately a change in b.
and positive means that the changes go in the same sign direction. increase => increase. decrease => decrease.
Related Questions
Solve the equation
tan^2 thetha-3 tan thetha+2=0 for 0
Answers
Step-by-step explanation:
[tex]\tan^2 \theta - 3\tan \theta + 2 = 0[/tex]
Let [tex]x = \tan \theta[/tex]
We can then write
[tex]x^2 -3x + 2 = 0\:\:\Rightarrow\:\:(x - 2)(x - 1) = 0[/tex]
or
[tex](\tan \theta - 2)(\tan \theta - 1) = 0[/tex]
The zeros occur when
[tex]\tan \theta = 2\:\:\:\text{or}\:\:\:\tan \theta = 1[/tex]
or when [tex]\theta = 63.4°[/tex] or [tex]\theta = 45°[/tex].
A student has test scores of 75 and 82respectively. What is the student’s average score for a third test
Answers
Answer:
78.5 (I think 90% sure)
Step-by-step explanation:
sum of both scores
75+82 = 157
average for a third test
157÷2=78.5
When f(x) is divided by x + 4 the quotient is x2+5x−3+2x+4. What is f(−4)?
Answers
=> f(-4)=((-4)2+5(-4)-3+2*(-4)+4)(-4+4)=0
F(-4)=0
please i need help with this rn
Answers
Hi there!
[tex]\large\boxed{f(9) = 12}[/tex]
Evaluating f(x) at x = 9 means we must use the piecewise function where x = 9 is included.
f(x) = 12 includes 9 because a "≤" is inclusive of the interval. Thus:
f(9) = 12
Amy worked 37.5 hours last week.
She is paid £11.50 per hour.
Her total deductions last week were £116.30.
What was Amy’s net pay last week?
£
Answers
First you must find out what the initial payment would have been, My way of doing it was simply multiplying 37 by 11.5
I then get 425.5, then to find out the amount for the .5 (half hour)simply divide 11.5,the answer is then £5.75,....now we add £425.5 + £5.75= £431.25
Now... we need to deduct her “deductions” lol which was £116.30 so
£431.25-£116.30=£314.95
So her payment was £314.95
Really hoped that helped have a wonderful day
Plz help ASAP problem down below
Answers
Explanation:
This is known as a cyclic quadrilateral since all four points are on the circle's edge, and the quadrilateral is entirely inside the circle (no parts of the quadrilateral spill outside the circle). Another term is "inscribed quadrilateral"
Since we have an inscribed quadrilateral, this means the opposite angles of the quadrilateral are supplementary.
B+D = 180
120+x = 180
x = 180-120
x = 60
Could someone help me
Answers
Hello,
I have only found 113 solutions (i have num 15 given)
nb= 1 ::: 27*n + 98= 30*n + 56===> n= 1 4
nb= 2 ::: 28*n + 95= 30*n + 67===> n= 1 4
nb= 3 ::: 29*n + 65= 30*n + 17===> n= 4 8
nb= 4 ::: 29*n + 65= 30*n + 18===> n= 4 7
nb= 5 ::: 29*n + 65= 30*n + 47===> n= 1 8
nb= 6 ::: 29*n + 65= 30*n + 48===> n= 1 7
nb= 7 ::: 29*n + 74= 30*n + 16===> n= 5 8
nb= 8 ::: 29*n + 74= 30*n + 18===> n= 5 6
nb= 9 ::: 29*n + 74= 30*n + 56===> n= 1 8
nb= 10 ::: 29*n + 74= 30*n + 58===> n= 1 6
nb= 11 ::: 30*n + 16= 29*n + 74===> n= 5 8
nb= 12 ::: 30*n + 17= 29*n + 65===> n= 4 8
nb= 13 ::: 30*n + 18= 29*n + 65===> n= 4 7
nb= 14 ::: 30*n + 18= 29*n + 74===> n= 5 6
nb= 15 ::: 30*n + 47= 29*n + 65===> n= 1 8
nb= 16 ::: 30*n + 48= 29*n + 65===> n= 1 7
nb= 17 ::: 30*n + 56= 27*n + 98===> n= 1 4
nb= 18 ::: 30*n + 56= 29*n + 74===> n= 1 8
nb= 19 ::: 30*n + 58= 29*n + 74===> n= 1 6
nb= 20 ::: 30*n + 67= 28*n + 95===> n= 1 4
nb= 21 ::: 36*n + 97= 40*n + 25===> n= 1 8
nb= 22 ::: 38*n + 59= 40*n + 27===> n= 1 6
nb= 23 ::: 38*n + 65= 40*n + 27===> n= 1 9
nb= 24 ::: 38*n + 69= 40*n + 15===> n= 2 7
nb= 25 ::: 39*n + 78= 45*n + 6===> n= 1 2
nb= 26 ::: 39*n + 82= 40*n + 15===> n= 6 7
nb= 27 ::: 39*n + 82= 40*n + 17===> n= 6 5
nb= 28 ::: 39*n + 82= 40*n + 65===> n= 1 7
nb= 29 ::: 39*n + 82= 40*n + 67===> n= 1 5
nb= 30 ::: 40*n + 15= 38*n + 69===> n= 2 7
nb= 31 ::: 40*n + 15= 39*n + 82===> n= 6 7
nb= 32 ::: 40*n + 17= 39*n + 82===> n= 6 5
nb= 33 ::: 40*n + 25= 36*n + 97===> n= 1 8
nb= 34 ::: 40*n + 27= 38*n + 59===> n= 1 6
nb= 35 ::: 40*n + 27= 38*n + 65===> n= 1 9
nb= 36 ::: 40*n + 65= 39*n + 82===> n= 1 7
nb= 37 ::: 40*n + 67= 39*n + 82===> n= 1 5
nb= 38 ::: 46*n + 87= 50*n + 39===> n= 1 2
nb= 39 ::: 46*n + 87= 52*n + 9===> n= 1 3
nb= 40 ::: 47*n + 68= 50*n + 29===> n= 1 3
nb= 41 ::: 47*n + 83= 50*n + 26===> n= 1 9
nb= 42 ::: 47*n + 98= 51*n + 6===> n= 2 3
nb= 43 ::: 47*n + 98= 53*n + 2===> n= 1 6
nb= 44 ::: 48*n + 63= 50*n + 29===> n= 1 7
nb= 45 ::: 48*n + 73= 52*n + 9===> n= 1 6
nb= 46 ::: 49*n + 63= 51*n + 7===> n= 2 8
nb= 47 ::: 49*n + 72= 53*n + 8===> n= 1 6
nb= 48 ::: 49*n + 78= 52*n + 30===> n= 1 6
nb= 49 ::: 49*n + 87= 56*n + 3===> n= 1 2
nb= 50 ::: 50*n + 26= 47*n + 83===> n= 1 9
nb= 51 ::: 50*n + 29= 47*n + 68===> n= 1 3
nb= 52 ::: 50*n + 29= 48*n + 63===> n= 1 7
nb= 53 ::: 50*n + 39= 46*n + 87===> n= 1 2
nb= 54 ::: 52*n + 30= 49*n + 78===> n= 1 6
nb= 55 ::: 57*n + 92= 63*n + 8===> n= 1 4
nb= 56 ::: 58*n + 72= 60*n + 34===> n= 1 9
nb= 57 ::: 58*n + 73= 60*n + 49===> n= 1 2
nb= 58 ::: 58*n + 79= 60*n + 31===> n= 2 4
nb= 59 ::: 58*n + 97= 60*n + 13===> n= 4 2
nb= 60 ::: 59*n + 47= 62*n + 8===> n= 1 3
nb= 61 ::: 59*n + 71= 60*n + 23===> n= 4 8
nb= 62 ::: 59*n + 71= 60*n + 28===> n= 4 3
nb= 63 ::: 59*n + 71= 60*n + 43===> n= 2 8
nb= 64 ::: 59*n + 71= 60*n + 48===> n= 2 3
nb= 65 ::: 59*n + 74= 63*n + 2===> n= 1 8
nb= 66 ::: 59*n + 78= 61*n + 30===> n= 2 4
nb= 67 ::: 59*n + 84= 61*n + 30===> n= 2 7
nb= 68 ::: 59*n + 87= 61*n + 3===> n= 4 2
nb= 69 ::: 60*n + 13= 58*n + 97===> n= 4 2
nb= 70 ::: 60*n + 23= 59*n + 71===> n= 4 8
nb= 71 ::: 60*n + 28= 59*n + 71===> n= 4 3
nb= 72 ::: 60*n + 31= 58*n + 79===> n= 2 4
nb= 73 ::: 60*n + 34= 58*n + 72===> n= 1 9
nb= 74 ::: 60*n + 43= 59*n + 71===> n= 2 8
nb= 75 ::: 60*n + 48= 59*n + 71===> n= 2 3
nb= 76 ::: 60*n + 49= 58*n + 73===> n= 1 2
nb= 77 ::: 61*n + 30= 59*n + 78===> n= 2 4
nb= 78 ::: 61*n + 30= 59*n + 84===> n= 2 7
nb= 79 ::: 65*n + 89= 70*n + 24===> n= 1 3
nb= 80 ::: 68*n + 59= 72*n + 3===> n= 1 4
nb= 81 ::: 68*n + 91= 70*n + 45===> n= 2 3
nb= 82 ::: 69*n + 43= 70*n + 15===> n= 2 8
nb= 83 ::: 69*n + 43= 70*n + 18===> n= 2 5
nb= 84 ::: 69*n + 43= 70*n + 25===> n= 1 8
nb= 85 ::: 69*n + 43= 70*n + 28===> n= 1 5
nb= 86 ::: 69*n + 48= 72*n + 3===> n= 1 5
nb= 87 ::: 69*n + 52= 70*n + 14===> n= 3 8
nb= 88 ::: 69*n + 52= 70*n + 18===> n= 3 4
nb= 89 ::: 69*n + 52= 70*n + 34===> n= 1 8
nb= 90 ::: 69*n + 52= 70*n + 38===> n= 1 4
nb= 91 ::: 69*n + 54= 71*n + 8===> n= 2 3
nb= 92 ::: 69*n + 58= 73*n + 2===> n= 1 4
nb= 93 ::: 69*n + 82= 75*n + 4===> n= 1 3
nb= 94 ::: 69*n + 85= 74*n + 20===> n= 1 3
nb= 95 ::: 70*n + 14= 69*n + 52===> n= 3 8
nb= 96 ::: 70*n + 15= 69*n + 43===> n= 2 8
nb= 97 ::: 70*n + 18= 69*n + 43===> n= 2 5
nb= 98 ::: 70*n + 18= 69*n + 52===> n= 3 4
nb= 99 ::: 70*n + 24= 65*n + 89===> n= 1 3
nb= 100 ::: 70*n + 25= 69*n + 43===> n= 1 8
nb= 101 ::: 70*n + 28= 69*n + 43===> n= 1 5
nb= 102 ::: 70*n + 34= 69*n + 52===> n= 1 8
nb= 103 ::: 70*n + 38= 69*n + 52===> n= 1 4
nb= 104 ::: 70*n + 45= 68*n + 91===> n= 2 3
nb= 105 ::: 74*n + 20= 69*n + 85===> n= 1 3
nb= 106 ::: 76*n + 93= 80*n + 45===> n= 1 2
nb= 107 ::: 79*n + 45= 82*n + 6===> n= 1 3
nb= 108 ::: 79*n + 54= 83*n + 6===> n= 1 2
nb= 109 ::: 80*n + 45= 76*n + 93===> n= 1 2
nb= 110 ::: 87*n + 64= 90*n + 25===> n= 1 3
nb= 111 ::: 87*n + 65= 90*n + 23===> n= 1 4
nb= 112 ::: 90*n + 23= 87*n + 65===> n= 1 4
nb= 113 ::: 90*n + 25= 87*n + 64===> n= 1 3
William has been contracted to paint a school classroom. The classroom is 20 m long, 15 m wide and 5 m high. There are four windows (2m by 3m) and a door (2m by 1m). Determine the cost of painting the ceiling at N$ 6.50/m²
Answers
Answer:
Step-by-step explanation:
l -> length
b -> width
h -> height
Find the area of four walls and ceiling. then subtract the area of four windows and a door form that area.
Area of four walls + ceiling = 2( lh + bh) +lb
= 2*(20*5 + 15*5) + 20*15
= 2( 100 + 75) + 300
= 2* 175 + 300
= 350 +300
= 650 sq m
Area of window = 2 *3 = 6 sq.m
Area of four windows = 4*6 = 24 sq.m
Area of door = 2 * 1 = 2 sq.m
Area of four walls excluding 4 windows and door = 650 - 24 - 2 = 624 sq.m
Cost of painting = 624 * 6.50
= $ 4056
Answer: 1950 dollars to paint the ceiling only (ignoring the walls)
The cost to paint the walls only is 2106 dollars.
The cost to paint the walls and ceiling is 4056 dollars.
==================================================
Explanation:
It seems a bit strange how your teacher mentions the windows and doors, but then asks about the ceiling only. Perhaps this is a red herring, but I'm not sure.
Anyway, to directly answer the question, we'll need to find the area of the ceiling first. The ceiling is a rectangle of dimensions 20 m by 15 m, so its area is 20*15 = 300 square meters.
Since paint costs 6.50 dollars per square meter, the total cost for the ceiling alone is 6.50*300 = 1950 dollars
If your teacher only cares about the ceiling, then you can stop here (and ignore the next section below).
---------------------------
If you wanted to find the cost to paint the walls, then we need to find the area of the walls.
For now, ignore the windows and door. Two opposite walls have area of 20*5 = 100 m^2 each. That accounts for 2*100 = 200 m^2 of wall area so far.
The other pair of opposite walls have area 15*5 = 75 m^2 each. That's another 2*75 = 150 m^2 of wall area.
In all, the total wall area without considering the windows or door is 200+150 = 350 m^2.
Now we consider the windows. Each window is 2 m by 3 m, yielding an area of 2*3 = 6 m^2. Four such windows have a total area of 4*6 = 24 m^2.
The door is 2 m by 1 m, so its area is 2*1 = 2 m^2
We'll subtract the wall area and the combined window+door areas to get
wallArea - windowArea - doorArea = 350-24-2 = 324
So after accounting for the windows and door, the amount of wall to paint is 324 m^2, which leads to a cost of 6.50*324 = 2106 dollars.
Therefore, painting the walls and ceiling gets us a total cost of 1950+2106 = 4056 dollars
This section is entirely optional if your teacher only cares about the ceiling.
if cars A and B are traveling at the speed of 55km/hr and 75km/hr respectively. What is their average speed?
Answers
Answer:
65 km/hr
Step-by-step explanation:
The average of numbers can be calculated by adding them up and dividing that by how many numbers there are.
Here, we have two numbers. Therefore, we first add them (55+75 = 130) and then divide by 2 because there are 2 numbers, so 130/2 = 65
using the 1 to 9 at the most time each, fill in the boxes to make a true statement
Answers
Answer:
2
Step-by-step explanation:
8*8 is 64
Since it looks like the empty box is an exponent, and there are 2 8s being multiplied, the answer is 2
What are the intercepts of the graphed function?
3
-2
Х
O x-intercept = (-1,0)
y-intercept = (-3,0)
O x-intercept = (0, -1)
y-intercept = (0, -3)
O x-intercept = (0, -1)
y-intercept = (-3,0)
x-intercept = (-1,0)
y-intercept = (0, -3)
6
Answers
Step-by-step explanation:
x intercept=(-1,0) because the graph is passing this point on the x axis
y intercept=(0,-3)
Answer:
4th option
Step-by-step explanation:
The x- intercept is where the graph crosses the x- axis.
This is at (- 1, 0 )
The y- intercept is where the graph crosses the y- axis.
This is at (0, - 3 )
how do you find the slope of -2
Answers
True or False: The points T, Z, W and U coplanar in the following image
Answers
Answer:
False
Step-by-step explanation:
Points T & W are coplanar. Point Z is on both planes, so it depends on how you see it. HOWEVER, Point U is on another plane (plane Q to be exact), so points T, Z, W, and U are NOT coplanar.
Hope it helps (●'◡'●)
Find the length of an arc that subtends a central angle of 224° in a circle of radius 20 m
Answers
Answer:
78.2m
Step-by-step explanation:
Lenght of the arc= ( circumference) × ( fraction of the circle)
Circumference=2πr = 2×20×π
Radius=20 m
fraction of the circle can be calculated as 224°/360°= 0.662
Then substitute the values we have
Lenght of the arc=
(2×20×π) ×0.662
= 78.2,
Lenght of the arc is 78.2m
Lendo 15 páginas por dia, Marcos leu um livro em
9 dias.
Para ler esse mesmo livro em 3 dias, quantas páginas
ele deveria ler por dia?
Answers
Answer:
Olha a foto.
Step-by-step explanation:
Assisted-Living Facility Rent. Costs are rising for all kinds of medical care. The mean monthly rent at assisted-living facilities was reported to have increased 17% over the last five years to $3486. Assume this cost estimate is based on a sample of 120 facilities and, from past studies, it can be assumed that the population standard deviation is .
Answers
Complete Question
Assisted-Living Facility Rent.Costs are rising for all kinds of medical care. The mean monthly rent at assisted-living facilities was reported to have increased 17% over the last five years to $3486 (the Wall Street Journal, October 27, 2012). Assume this cost estimate is based on a sample of 120 facilities and, from past studies, it can be assumed that the population standard deviation is s = $650. a. Develop a 90% confidence interval estimate of the population mean monthly rent.
Answer:
[tex]CI: 3388.39<X<3583.61[/tex]
Step-by-step explanation:
Sample Size n=120
Mean \=x =3486
Standard Deviation \sigma=650
Confidence interval CI=0.9
Therefore
Level of sig [tex]\alpha=0.1[/tex]
Therfore
The Critical Value from table is
Z_c=1.645
Generally the equation for Standard error is mathematically given by
[tex]S.E=\frac{\sigma}{\sqrt{n}}[/tex]
[tex]S.E=\frac{650}{\sqrt{120}}[/tex]
[tex]S.E=59.3366[/tex]
Generally the equation for Margin error is mathematically given by
[tex]M.E= = Z_c * SE[/tex]
[tex]M.E=1.65 * 59.34[/tex]
[tex]M.E= 97.61[/tex]
Therefore
[tex]CI= \=x \pm M.E[/tex]
[tex]CI= 3486 \pm 97.61[/tex]
Lower limit
[tex]LL= \=x-M.E=3486-97.6087[/tex]
[tex]LL= 3388.39[/tex]
Upper limit:
[tex]UL= \=x+E=3486+97.6087[/tex]
[tex]UL= 3583.61[/tex]
Therefore The 90% confidence interval estimate of the population mean monthly rent.
[tex]CI: 3388.39<X<3583.61[/tex]
What are the roots of the polynomial equation x3 - 6x= 3x2 - 8? Use a graphing calculator and a system of equations
Answers
Answer:
Hence, the roots of the polynomial equation are:
-2, 1, 4
Step-by-step explanation:
We are asked to find the roots of the polynomial equation:
We can also equate this equation to y to obtain a system of equation as:
and
Hence, the roots of the polynomial; equation are the x-values of the point of intersections of the graph of the system of equations.
Hence, the point of intersection of the two graphs are:
(-2,4), (1,-5) and (4,40)
Hence, the roots of the polynomial equation are:
-2, 1, 4
4/5×1 1/9÷2 2/3. please help me
Answers
Answer:
1/3
Step-by-step explanation:
when you change the mixed numbers to improper fractions, you get 4/5 * 10/9 ÷ 8/3. you can flip the 8/3 to 3/8 and change the division sign to multiplication, because dividing by a fraction is the same as multiplying by its reciprocal. you can cancel some things and ultimately you get 1/3
1/3=?/24
Which number is missing to make the equation true?
Answers
Answer:
8
Step-by-step explanation:
Find in the triangle. Round to the nearest degree.
Answers
Answer:
D. 34
Step-by-step explanation:
Because this is a right triangle we can use sin, cos, tan.
Use cosine because the values of the adjacent side and hypotenuse are already given.
cos(θ) = 72/87
Because we are solving for the angle measure (and not the measure of the side) we need to use inverse cos.
cos⁻¹ = 72/87
put into a calculator and answer is approximatelyn34 degrees.
write 16.76 correct to the nearest whole number
Answers
After the dot if it’s 1-4 then they it would’ve been 15
5-9 is 17
Answer:
17
Step-by-step explanation:
because they are both above 5 so add 1
b) The cost of 1 kg of sweets is Rs 750. Find the cost of 1 kg sweet. 2
Answers
Find the direction cosines and direction angles of the vector. (Give the direction angles correct to the nearest degree.) c, c, c , where c > 0
Answers
Answer:
cos(∝) = 1/√3
cos(β) = 1/√3
cos(γ) = 1/√3
∝ = 55°
β = 55°
γ = 55°
Step-by-step explanation:
Given the data in the question;
vector is z = < c,c,c >
the direction cosines and direction angles of the vector = ?
Cosines are the angle made with the respect to the axes.
cos(∝) = z < 1,0,0 > / |z|
so
cos(∝) = < c,c,c > < 1,0,0 > / √[c² + c² + c²] = ( c + 0 + 0 ) / √[ 3c² ]
cos(∝) = c / √[ 3c² ] = c / c√3 = 1/√3
∝ = cos⁻¹( 1/√3 ) = 54.7356° ≈ 55°
cos(β) = < c,c,c > < 0,1,0 > / √[c² + c² + c²] = ( 0 + c + 0 ) / √[ 3c² ]
cos(β) = c / √[ 3c² ] = c / c√3 = 1/√3
β = cos⁻¹( 1/√3 ) = 54.7356° ≈ 55°
cos(γ) = < c,c,c > < 0,0,1 > / √[c² + c² + c²] = ( 0 + 0 + c ) / √[ 3c² ]
cos(γ) = c / √[ 3c² ] = c / c√3 = 1/√3
γ = cos⁻¹( 1/√3 ) = 54.7356° ≈ 55°
Therefore;
cos(∝) = 1/√3
cos(β) = 1/√3
cos(γ) = 1/√3
∝ = 55°
β = 55°
γ = 55°
It has been determined that 60% of the people in a certain midwest city who are responsible for preparing the evening meal have no idea what they are going to prepare as late as 4PM in the afternoon. A recent survey was conducted from 1000 of these individuals. For the sampling distribution of the sample proportion to be reasonably Normal, the sample must have been obtained in the right way (ideally, a simple random sample) and the sample size must be large (so that at least 10 or more successes and failures). Are these conditions met
Answers
Answer:
Random sample, [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex], so yes, both conditions were satisfied.
Step-by-step explanation:
60% of the people in a certain midwest city who are responsible for preparing the evening meal have no idea what they are going to prepare as late as 4PM in the afternoon.
This means that [tex]p = 0.6[/tex]
A recent survey was conducted from 1000 of these individuals.
This means that [tex]n = 1000[/tex]
Also, a random sample, so the first condition was satisfied.
The sample size must be large (so that at least 10 or more successes and failures).
[tex]np = 1000*0.6 = 600 \geq 10[/tex]
[tex]n(1-p) = 1000*0.4 = 400 \geq 10[/tex]
So yes, both conditions were met.
The table gives estimates of the world population, in millions, from 1750 to 2000. (Round your answers to the nearest million.)
Year Population
1750 790
1800 980
1850 1260
1900 1650
1950 2560
2000 6080
(a) Use the exponential model and the population figures for 1750 and 1800 to predict the world population in 1900 and 1950 1900 1950 million people million people
(b) Use the exponential model and the population figures for 1800 and 1850 to predict the world population in 1950 million people
(c) Use the exponential model and the population figures for 1900 and 1950 to predict the world population in 2000 million people
Answers
Answer:
A.) 1508 ; 1870
B.) 2083
C.) 3972
Step-by-step explanation:
General form of an exponential model :
A = A0e^rt
A0 = initial population
A = final population
r = growth rate ; t = time
1)
Using the year 1750 and 1800
Time, t = 1800 - 1750 = 50 years
Initial population = 790
Final population = 980
Let's obtain the growth rate :
980 = 790e^50r
980/790 = e^50r
Take the In of both sides
In(980/790) = 50r
0.2155196 = 50r
r = 0.2155196/50
r = 0.0043103
Using this rate, let predict the population in 1900
t = 1900 - 1750 = 150 years
A = 790e^150*0.0043103
A = 790e^0.6465588
A = 1508.0788 ; 1508 million people
In 1950;
t = 1950 - 1750 = 200
A = 790e^200*0.0043103
A = 790e^0.86206
A = 1870.7467 ; 1870 million people
2.)
Exponential model. For 1800 and 1850
Initial, 1800 = 980
Final, 1850 = 1260
t = 1850 - 1800 = 50
Using the exponential format ; we can obtain the rate :
1260 = 980e^50r
1260/980 = e^50r
Take the In of both sides
In(1260/980) = 50r
0.2513144 = 50r
r = 0.2513144/50
r = 0.0050262
Using the model ; The predicted population in 1950;
In 1950;
t = 1950 - 1800 = 150
A = 980e^150*0.0050262
A = 980e^0.7539432
A = 2082.8571 ; 2083 million people
3.)
1900 1650
1950 2560
t = 1900 - 1950 = 50
Using the exponential format ; we can obtain the rate :
2560 = 1650e^50r
2560/1650 = e^50r
Take the In of both sides
In(2560/1650) = 50r
0.4392319 = 50r
r = 0.4392319/50
r = 0.0087846
Using the model ; The predicted population in 2000;
In 2000;
t = 2000 - 1900 = 100
A = 1650e^100*0.0087846
A = 1650e^0.8784639
A = 3971.8787 ; 3972 million people
Please help very appreciated
Answers
the good construction slithers 3/9 kilometers in 3/6 hours . wat is it's speed in terms of kilometers per hour ?
Answers
Answer:
The speed in terms of kilometers per hour is 0.666 km / h.
Step-by-step explanation:
Given that the good construction slithers 3/9 kilometers in 3/6 hours, to determine what is it's speed in terms of kilometers per hour, the following calculation must be performed:
3/9 = 0.333 km
3/6 = 0.5 hours
0.666 km / h
Therefore, the speed in terms of kilometers per hour is 0.666 km / h.
You work for a parts manufacturing company and are tasked with exploring the wear lifetime of a certain bearing. You gather data on oil viscosity used and load. You see the regression output given below.
Predictor Coef Stdev t-ratio P
Constant -147.973 41.972 -3.53 0.004181
viscosity 6.262 0.474 13.21 <0.0001
load 0.298 0.04 7.43 <0.0001
s = 13.507 R² = 95.73% R² (adj = 95.02%
Analysis of Variance
Source DF SS MS F
Regression 2 49131.93 24565.96 134.65
Error 12 2189.38 182.45
Total 14 51321.3
Required:
What is the correct conclusion about the regression slopes based solely on the F-test
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Answer:
We reject the Null and conclude that There is significant evidence that the slope values are greater than 0.
Step-by-step explanation:
Based on the ANOVA output given :
The F critical value can be obtained thus ;
F(df regression, df error)
Using an α-value of 0.01
F(2, 12) at α = 0.01 is 6.927
The F statistic as obtained from the ANOVA table = 134.65
Since, F statistic > F critical we reject the Null and conclude that slope values are significantly > 0
Similarly,
Using the Pvalue :
The Pvalue of the slope are extremely small :
Viscosity <0.0001
Load <0.0001
At α = 0.01, 0.025
The Pvalue < α ; The null will be rejected.
In this diagram, ABAC – AEDF. If the
area of ABAC = 6 in?, what is the
area of AEDF?
Answers
Answer:
2.7 in²
Step-by-step explanation:
similar triangles have the same angles, and all side lengths (or other distances) of one triangle have the same scaling factor to the side lengths of the other triangle.
so, we know the relation between the 2 baselines is 2/3, as this is the factor to turn the baseline of the large triangle into the baseline of the smaller triangle.
in other words
EF = BC × 2/3
2 = 3 × 2/3
correct
how do we calculate the area of a triangle ?
Area = baseline × height / 2
from BAC we know
Area = 6
baseline = 3
height = ?
6 = 3 × height / 2
12 = 3 × height
height = 4
aha !
now, EDF has a height too that we need to calculate is Area. and this height has the same scaling factor compared to the larger triangle as the side lengths : 2/3
so, for EDF we know
Area = ?
baseline = 2
height = 4 × 2/3 = 8/3
therefore, the area is
Area = (2 × 8/3) / 2 = (16/3) / 2 = 8/3 = 2.66666... ≈ 2.7
the shirt answer would be :
we know from the 2 baselines that the scaling factor for each distance is 2/3.
for the area we need to multiply 2 distances, so that means we have to multiply both by 2/3. and so on the formula for the area we have to use 2/3 × 2/3.
2/3 × 2/3 = 4/9
=>
Area small = Area large × 4/9 = 6 × 4/9 = 24/9 = 8/3 ≈ 2.7
math help plz
how to solve parabola and its vertex, how to understand easily and step by step with an example provided please
Answers
Answer:
The general equation for a parabola is:
y = f(x) = a*x^2 + b*x + c
And the vertex of the parabola will be a point (h, k)
Now, let's find the values of h and k in terms of a, b, and c.
First, we have that the vertex will be either at a critical point of the function.
Remember that the critical points are the zeros of the first derivate of the function.
So the critical points are when:
f'(x) = 2*a*x + b = 0
let's solve that for x:
2*a*x = -b
x = -b/(2*a)
this will be the x-value of the vertex, then we have:
h = -b/(2*a)
Now to find the y-value of the vertex, we just evaluate the function in this:
k = f(h) = a*(-b/(2*a))^2 + b*(-b/(2*a)) + c
k = -b/(4*a) - b^2/(2a) + c
So we just found the two components of the vertex in terms of the coefficients of the quadratic function.
Now an example, for:
f(x) = 2*x^2 + 3*x + 4
The values of the vertex are:
h = -b/(2*a) = -3/(2*2) = -3/4
k = -b/(4*a) - b^2/(2a) + c
= -3/(4*2) - (3)^2/(2*2) + 4 = -3/8 - 9/4 + 4 = (-3 - 18 + 32)/8 = 11/8
