Answer:
See below.
Step-by-step explanation:
To find roots of an equation, we use this formula:
[tex]z^{\frac{1}{n}}=r^{\frac{1}{n}}(cos(\frac{\theta}{n}+\frac{2k\pi}{n} )+\mathfrak{i}(sin(\frac{\theta}{n}+\frac{2k\pi}{n})),[/tex] where k = 0, 1, 2, 3... (n = root; equal to n - 1; dependent on the amount of roots needed - 0 is included).
In this case, n = 4.
Therefore, we adjust the polar equation we are given and modify it to be solved for the roots.
Part 2: Solving for root #1
To solve for root #1, make k = 0 and substitute all values into the equation. On the second step, convert the measure in degrees to the measure in radians by multiplying the degrees measurement by [tex]\frac{\pi}{180}[/tex] and simplify.
[tex]z^{\frac{1}{4}}=16^{\frac{1}{4}}(cos(\frac{200}{4}+\frac{2(0)\pi}{4}))+\mathfrak{i}(sin(\frac{200}{4}+\frac{2(0)\pi}{4}))[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\frac{\pi}{4}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{\pi}{4}))[/tex]
[tex]z^{\frac{1}{4}} = 2(sin(\frac{5\pi}{18}+\frac{\pi}{4}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{\pi}{4}))[/tex]
Root #1:
[tex]\large\boxed{z^\frac{1}{4}=2(cos(\frac{19\pi}{36}))+\mathfrack{i}(sin(\frac{19\pi}{38}))}[/tex]
Part 3: Solving for root #2
To solve for root #2, follow the same simplifying steps above but change k to k = 1.
[tex]z^{\frac{1}{4}}=16^{\frac{1}{4}}(cos(\frac{200}{4}+\frac{2(1)\pi}{4}))+\mathfrak{i}(sin(\frac{200}{4}+\frac{2(1)\pi}{4}))[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\frac{2\pi}{4}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{2\pi}{4}))\\[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\frac{\pi}{2}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{\pi}{2}))\\[/tex]
Root #2:
[tex]\large\boxed{z^{\frac{1}{4}}=2(cos(\frac{7\pi}{9}))+\mathfrak{i}(sin(\frac{7\pi}{9}))}[/tex]
Part 4: Solving for root #3
To solve for root #3, follow the same simplifying steps above but change k to k = 2.
[tex]z^{\frac{1}{4}}=16^{\frac{1}{4}}(cos(\frac{200}{4}+\frac{2(2)\pi}{4}))+\mathfrak{i}(sin(\frac{200}{4}+\frac{2(2)\pi}{4}))[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\frac{4\pi}{4}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{4\pi}{4}))\\[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\pi))+\mathfrak{i}(sin(\frac{5\pi}{18}+\pi))\\[/tex]
Root #3:
[tex]\large\boxed{z^{\frac{1}{4}}=2(cos(\frac{23\pi}{18}))+\mathfrak{i}(sin(\frac{23\pi}{18}))}[/tex]
Part 4: Solving for root #4
To solve for root #4, follow the same simplifying steps above but change k to k = 3.
[tex]z^{\frac{1}{4}}=16^{\frac{1}{4}}(cos(\frac{200}{4}+\frac{2(3)\pi}{4}))+\mathfrak{i}(sin(\frac{200}{4}+\frac{2(3)\pi}{4}))[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\frac{6\pi}{4}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{6\pi}{4}))\\[/tex]
[tex]z^{\frac{1}{4}}=2(cos(\frac{5\pi}{18}+\frac{3\pi}{2}))+\mathfrak{i}(sin(\frac{5\pi}{18}+\frac{3\pi}{2}))\\[/tex]
Root #4:
[tex]\large\boxed{z^{\frac{1}{4}}=2(cos(\frac{16\pi}{9}))+\mathfrak{i}(sin(\frac{16\pi}{19}))}[/tex]
The fourth roots of 16(cos 200° + i(sin 200°) are listed above.
This year Alex’s age is 1/6 of his dads. Four years later, Alex’s age is 1/4 of his dads. How old is Alex and his dad this year?
Answer:
This year:
dads: 36 years
Alex: 6 years
Step-by-step explanation:
a = d/6
a+4 = (d+4)/4
a = Alex´s actual age
d = actual age of the dad
d/6 + 4 = (d+4)/4
4{(d/6) + 4} = d+4
4*d/6 + 4*4 = d+4
4d/6 + 16 = d + 4
4d/6 = d + 4 - 16
4d = (d-12)*6
4d = 6*d +6*-12
4d = 6d - 72
4d - 6d = -72
-2d = -72
d = -72/-2
d = 36
a = d/6
a = 36/6
a = 6
probe:
a+4 = (d+4)/4
6 + 4 = (36+4)/4
10 = 40/4
V(x)=-x2+2x-4 and W(x)=-x3+2x2+x+5 Find V(x)-W(x)
Answer:
[tex]-x^3-x^2+x-9[/tex]
Step-by-step explanation:
Distribute -1
Combine Like Terms
[tex](x^2+2x-4)-(x^3+2x^2+x+5)\\= x^2+2x-4+-x^3-2x-x-5\\= -x^3-x^2+x-9[/tex]
Answer:
[tex]x^{3} -3x^{2} +x-9[/tex]
Step-by-step explanation:
-x^2+2x-4-(-x^3+2x^2+x+5)
Combine like terms
x^3-3x^2+x-9
What number is halfway between 250 and 300
Answer:
the number that is halfway between 250 and 300 is 275
Step-by-step explanation:
250+300= 550/2= 275
The number i,e halfway is 275.
Important information:The two numbers is 250 and 300.calculation:[tex]= (250 + 300) \div 2\\\\= 550 \div 2[/tex]
= 275
Find out more information about the Number here : https://brainly.com/question/17429689?referrer=searchResults
A sample of 255 observations is selected from a normal population with a population standard deviation of 27. The sample mean is 20. Determine the standard error of the mean.
Answer:
1.691
Step-by-step explanation:
Standard error of the mean is expressed as SEM = S/√n
S is the population standard deviation
n is the sample size (number of observation)
Given S = 27 and n = 255
SEM = 27/√255
SEM = 27/15.97
SEM = 1.691
Hence the standard error of the mean is 1.691
What is an equation of the line that passes through the points (-5, 8) and (5,0)?
Answer:
y= -0.8x + 4
Midpoint is 0,4
During two years in college, a student earned $9,500. The second year she earned $500 more than twice the amount she earned the first year. How much did she earn the first year?
If the function Q(t)=4e-0.00938t models the quantity (in kg) of an element in a storage unit after t years, how long will it be before the quantity is less than 1.5kg? Round to the nearest year.
Answer:
105 years
Step-by-step explanation:
Given the function :
Q(t) = 4e^(-0.00938t)
Q = Quantity in kilogram of an element in a storage unit after t years
how long will it be before the quantity is less than 1.5kg
Inputting Q = 1.5kg into the equation:
1.5 = 4e^(-0.00938t)
Divide both sides by 4
(1.5 / 4) = (4e^(-0.00938t) / 4)
0.375 = e^(-0.00938t)
Take the ln of both sides
In(0.375) = In(e^(-0.00938t))
−0.980829 = -0.00938t
Divide both sides by 0.00938
0.00938t / 0.00938 = 0.980829 /0.00938
t = 104.56599
When t = 104.56599 years , the quantity in kilogram of the element in storage will be exactly 1.5kg
Therefore, when t = 105 years, the quantity of element in storage will be less than 1.5kg
If you rent a car for one day and drive it for 100 miles the cost is 40 dollars if you drive it 220 miles the cost is 46 dollars what is the linear equation for this
Answer:
[tex] y = \dfrac{1}{20}x + 35 [/tex]
Step-by-step explanation:
Let y = cost.
Let x = number of miles.
We have two (x, y) points: (100, 40) and (220, 46).
Now we find the equation of the line that passes through those two points using the two-point form of the equation of a line.
[tex] y - y_1 = \dfrac{y_2 - y_1}{x_2 - x_1}(x - x_1) [/tex]
[tex] y - 40 = \dfrac{46 - 40}{220 - 100}(x - 100) [/tex]
[tex] y - 40 = \dfrac{6}{120}(x - 100) [/tex]
[tex] y - 40 = \dfrac{1}{20}(x - 100) [/tex]
[tex] y - 40 = \dfrac{1}{20}x - 5 [/tex]
[tex] y = \dfrac{1}{20}x + 35 [/tex]
The sum of the reciprocals of two consecutive even integers is 3/4
Find the two integers.
[tex] \Large{ \underline{ \underline{ \bf{ \orange{Solution:}}}}}[/tex]
Let one of those even numbers be x, Then other even number would be x + 2.
According to question,
⇛ Their reciprocal add upto 3/4
So, we can write it as,
⇛ 1/x + 1/x + 2 = 3/4
⇛ x + 2 + x / x(x + 2) = 3/4
⇛ 2x + 2 / x² + 2x = 3/4
Cross multiplying,
⇛ 3(x² + 2x) = 4(2x + 2)
⇛ 3x² + 6x = 8x + 8
⇛ 3x² - 2x - 8 = 0
⇛ 3x² - 6x + 4x - 8 = 0
⇛ 3x(x - 2) + 4(x - 2) = 0
⇛ (3x + 4)(x - 2) = 0
Then, x = -4/3 or 2
☃️ It can't be -4/3 because it is fraction and negative number. So, x = 2
Then, x + 2 = 4
✤ So, The even numbers are 2 and 4.
━━━━━━━━━━━━━━━━━━━━
PLEASE HELP!!
Solve for y
a) 8
b) 12
c) 3V7
d) 4V7
Answer:
C. [tex] y = 3\sqrt{7} [/tex]
Step-by-step explanation:
Based on the right triangle altitude theorem, the altitude, y, in the diagram above, equals the geometric mean of 9 and 7.
This implies => [tex] y = \sqrt{9*7} [/tex]
Thus, solve for y.
[tex] y = \sqrt{9} * \sqrt{7} [/tex]
[tex] y = 3\sqrt{7} [/tex]
The answer is C. [tex] y = 3\sqrt{7} [/tex]
If 6x +3= 2x+ 19, then x =
Answer:
x = 4
Step-by-step explanation:
6x + 3 = 2x + 19 ------ subtract 3 both sides
6x + 3 - 3 = 2x + 19 - 3 simplify
6x = 2x + 16 ------ subtract 2x both sides
6x - 2x = 2x + 16 - 2x simplify
4x = 16
x = 16 / 4
x = 4
Answer: x = 4
Step-by-step explanation: If the variable appears on both sides of the equation, we put the variables together on one side of the equation and the numbers together on the other side of the equation.
So let's put our variables on the left side by first subtracting
2x from both sides of the equation to get 4x + 3 = 19.
Next, we subtract 3 from both sides to get 4x = 16.
Finally, we divide both sides by 4 to get x = 4.
Solve the system of inequalities: y + 2x > 3 and y Greater-than-or-equal-to 3.5x − 5 The first inequality, y + 2x > 3, is in slope-intercept form. The first inequality, y + 2x > 3, has a boundary line. The second inequality, y Greater-than-or-equal-to 3.5x − 5, has a boundary line. Both inequalities have a solution set that is shaded their boundary lines. is a point in the solution set of the system of inequalities.
Answer:
y>-2x+3
Dashed
Solid
Above
(1, 5)
Step-by-step explanation:
Edge2020
The slope-intercept form of the first inequality is (y > - 2x + 3), the first inequality has dash boundary lines because the sign of the inequality is ">", and the second inequality has solid boundary lines because the sign of the inequality is [tex]\geq[/tex].
Given :
[tex]\rm y+2x>3[/tex][tex]\rm y \geq 3.5x -5[/tex]The slope-intercept form of a line is given by:
y = mx + c
So, the slope-intercept form of the first inequality is:
y > - 2x + 3
The first inequality has dash boundary lines because the sign of the inequality is ">".
The second inequality has solid boundary lines because the sign of the inequality is [tex]\geq[/tex].
For more information, refer to the link given below:
https://brainly.com/question/19491153
i will give brainliest and 5 stars if you help ASAP
Answer:
£39.20
Step-by-step explanation:
→ Identify which ratio goes to each person
2 : 1 : 5
2 = Paul
1 = Colin
5 = Brian
→ Divide the total tip by the total sum of the ratio's
£78.40 ÷ ( 2 + 1 + 5 ) ⇔ £78.40 ÷ 8 = £9.80
→ Now we know one part is equal to £9.80 we multiply this number by each of the associated ratio's
Paul = £9.80 × 2 ⇔ £19.60
Colin = £9.80 × 1 ⇔ £9.80
Brian = £9.80 × 5 ⇔ £49
→ Minus Brian's tip against Colin's tip
£49 - £9.80 = £39.20
Solve 2(x - 1) + 3 = x - 3(x + 1) (make sure to type the number only)
Answer:
x = -1
Step-by-step explanation:
2(x - 1) + 3 = x - 3(x + 1)
Distribute
2x -2+3 = x -3x-3
Combine like terms
2x +1 = -2x-3
Add 2x to each side
2x+1 +2x = -2x-3+2x
4x+1 = -3
Subtract 1 from each side
4x+1-1 = -3-1
4x= -4
Divide by 4
4x/4 = -4/4
x = -1
find the value of X?
Answer:
x = 58
Step-by-step explanation:
The exterior angle is equal to the sum of the opposite interior angles
90 = 32+x
Subtract 32 from each side
90-32 = x
58 =x
How many ways are there to choose 22 croissants with at least one plain croissant, at least two cherry croissants, at least three chocolate croissants, at least one almond croissant, at least two apple croissants, and no more than three broccoli croissants
Answer:
There are 6566 ways to choose 22 croissants with at least one plain croissant, at least two cherry croissants, at least three chocolate croissants, at least one almond croissant, at least two apple croissants, and no more than three broccoli croissants.
Step-by-step explanation:
Given:
There are 5 types of croissants:
plain croissants
cherry croissants
chocolate croissants
almond croissant
apple croissants
broccoli croissants
To find:
to choose 22 croissants with:
at least one plain croissant
at least two cherry croissants
at least three chocolate croissants
at least one almond croissant
at least two apple croissants
no more than three broccoli croissants
Solution:
First we select
At least one plain croissant to lets say we first select 1 plain croissant, 2 cherry croissants, 3 chocolate croissants, 1 almond croissant, 2 apple croissants
So
1 + 2 + 3 + 1 + 2 = 9
Total croissants = 22
So 9 croissants are already selected and 13 remaining croissants are still needed to be selected as 22-9 = 13, without selecting more than three broccoli croissants.
n = 5
r = 13
C(n + r - 1, r)
= C(5 + 13 - 1, 13)
= C(17,13)
[tex]=\frac{17! }{13!(17-13)!}[/tex]
= 355687428096000 / 6227020800 ( 24 )
= 355687428096000 / 149448499200
= 2380
C(17,13) = 2380
C(n + r - 1, r)
= C(5 + 12 - 1, 12)
= C(16,12)
[tex]=\frac{16! }{12!(16-12)!}[/tex]
= 20922789888000 / 479001600 ( 24 )
= 20922789888000 / 11496038400
= 1820
C(16,12) = 1820
C(n + r - 1, r)
= C(5 + 11 - 1, 11)
= C(15,11)
[tex]=\frac{15! }{11!(15-11)!}[/tex]
= 1307674368000 / 39916800 (24)
= 1307674368000 / 958003200
= 1307674368000 / 958003200
= 1365
C(15,11) = 1365
C(n + r - 1, r)
= C(5 + 10 - 1, 10)
= C(14,10)
[tex]=\frac{14! }{10!(14-10)!}[/tex]
= 87178291200 / 3628800 ( 24 )
= 87178291200 / 87091200
= 1001
C(14,10) = 1001
Adding them:
2380 + 1820 + 1365 + 1001 = 6566 ways
can someone show me how to do this please
Answer:
[tex]volume = 0.32 m^3[/tex]
Step-by-step explanation:
The object shown above consists of 5 cubes having side lengths of ⅖m each.
Volume of a cube = [tex] a^3 [/tex]
Where, a = side length = ⅖ m
Volume of the object = [tex]5* (\frac{2}{5})^3[/tex]
[tex]volume = 5*\frac{8}{125} = 5*0.064 = 0.32 m^3[/tex]
Hakim is making a mosaic
from square tiles. The area he
needs to fill measures 150 mm
by 180 mm. The tiles have side
lengths of 4, 6 or 8 mm and are
too small to cut. Which tiles
should Hakim use?
Answer:
6×6 tile
Step-by-step explanation:
First let's calculate the total area Hakim should fill.
Let A be that area.
The area is a rectangle so its area is the product of the length and the width.
● A = 180*150
● A = 27000 mm^2
■■■■■■■■■■■■■■■■■■■■■■■■■■
The tiles Hakim has are all squares with different sides(4,6,8).
Let calculate the area of each tile.
Let A' , A" and A"' be the areas respectively of the 4,6 and 8 squares.
Since all tiles are squares, the area is the side times itself.
■■■■■■■■■■■■■■■■■■■■■■■■■■
● A' = 4^2 = 16 mm^2
● A" = 6^2 = 36 mm^2
● A"' = 8^2 = 64 mm^2
Divide the total area by each area and see wich one will give you a whole number.
●A÷A' = 27000÷16 = 1687.5
This isn't a whole number
● A÷A" = 27000÷36 = 750
This is a whole number, so it is the right tile.
● A+A"' = 27000÷64 = 421.875
This isn't the right tile.
Hakil should use the 6×6 tile
Hakim should use a tile of 6×6 side.
What is area?The area is the region bounded by the shape of an object. The space covered by the figure or any two-dimensional geometric shape, in a plane, is the area of the shape.
Given that, Hakim is making a mosaic from square tiles. The area he needs to fill measures 150 mm by 180 mm. The tiles have side lengths of 4, 6 or 8 mm and are too small to cut.
To know that which tile fits best, we will divide the area of mosaic to the area of the tile, and see if we get a whole number if not a whole number then it should be cut, but we are restricted to do so, therefore we will look for the whole number,
Area of the mosaic = 150×180 = 27000 mm²
Area of the tile with side 4 mm = 4² = 16 mm²
Number of tile = 27000/16 = 1687.5 tiles. (not a whole number)
Area of the tile with side 6 mm = 6² = 36 mm
Number of tile = 27000/36 = 750 tile. (a whole number)
Hence, Hakim should use a tile of 6×6 side.
For more references on area, click;
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The fastest fish in the world is the sailfish. If a
sailfish could maintain its speed, as shown in the
table, how many miles could the sailfish travel in 6
hours?
p.s the top is hour traveled and the bottom is miles traveled
Answer:
(C) 408 miles
Step-by-step explanation:
Looking at this table, we can see that the beginning point is (0,0) so this is a linear slope, meaning we won’t have to add anything.
This means that for every time we rise in x, y will rise by the same amount.
When x is 1, y is 68 - so the constant of proportionality here is 68.
So, to find how much 6 hours would be we just multiply.
[tex]6\cdot68=408[/tex]
Hope this helped!
PLEASE HELP MEEEEEEEEEEEEEEE
Answer:
x=16.1
Step-by-step explanation:
open the brackets
-4.5= -0.5x-3.55
Take 3.55 to the other side.
-4.5-3.55 = -8.05
5/10x= -805/100
0.5x= - 8.05 = 16.1
Given: AQRS where m2Q = 20° and m2S = 90°
R
1,000 meters
Q
S
What is the length of segment RS?
342 m
364 m
500 m
940 m
Answer:
342 m
Step-by-step explanation:
SIn(20) * 1000 = RS
342 = RS
F
13
5
H
12
G
se
Find mZH to the nearest degree.
67
O 18
O 45
O 23
Answer:
∠ H ≈ 23°
Step-by-step explanation:
Using the tangent ratio in the right triangle
tan H = [tex]\frac{opposite}{adjacent}[/tex] = [tex]\frac{FG}{HG}[/tex] = [tex]\frac{5}{12}[/tex] , thus
∠ H = [tex]tan^{-1}[/tex] ( [tex]\frac{5}{12}[/tex] ) ≈ 23° ( to the nearest degree )
Assume that a randomly selected subject is given a bone density test. Those test scores are normally distributed with a mean of 0 and a standard deviation of 1. Find the probability that a given score is less than 1.99 and draw a sketch of the region.
Answer:
Step-by-step explanation:
To find this probability, we shall be using the z-score route
Mathematically ;
z-score = (x -mean)/SD
From the question, x = 1.99, mean = 0 and SD = 1
So z = (1.99-0)/1 = 1.99
So the probability we want to calculate is;
P(z<1.99)
This value can be obtained from the standard normal distribution table.
P(z < 1.99) = 0.9767
The sketch of the region is as shown as in the attachment.
limit chapter~ anyone can help me with these questions?
please gimme clear explanation :)
Step-by-step explanation:
I(S) = aS / (S + c)
As S approaches infinity, S becomes much larger than c. So S + c is approximately equal to just S.
lim(S→∞) I(S)
= lim(S→∞) aS / (S + c)
= lim(S→∞) aS / S
= lim(S→∞) a
= a
As S approaches infinity, I(S) approaches a.
PLZZZZZZZZZZZZZZ HELP I WILL GIVE BRAINLIEST TO THE FIRST TO ANSWER
Answer:
B
Step-by-step explanation:
-(-a)/b = a/b
Option A is not equal to a/b
But Option B is, after cancelling out the negative sign
Answer:
[tex]\large \boxed{ \mathrm{B.} \ - \frac{a}{-b} }[/tex]
Step-by-step explanation:
[tex]\displaystyle -\frac{-a}{b} =-(- \frac{a}{b} ) = \frac{a}{b}[/tex]
The first option is not equivalent to a/b.
[tex]\displaystyle \frac{a}{-b}\neq \frac{a}{b}[/tex]
The second option is equivalent to a/b.
[tex]\displaystyle -\frac{a}{-b} =\frac{-a}{-b} = \frac{a}{b}[/tex]
At the dog show, there are 4 times as many boxers as spaniels. If there are a total of 30 dogs,how many dogs are spaniels? Plz help me
Answer:
6 spaniels
Step-by-step explanation:
Create 2 equations to represent this, where b is the number of boxers and s is the number of spaniels:
4s = b
s + b = 30
We can plug in 4s as b into the second equation, s + b = 30:
s + b = 30
s + 4s = 30
5s = 30
s = 6
So, there are 6 spaniels.
One winter day, the temperature ranged from a high of 20 degrees to a low of -25 degrees. By how many degrees did the temperature change?
Answer:
+20° to -25° = 45° C/F temperature change
Step-by-step explanation:
The graph represents this system of equations
y=4
y=3 - 1/2x . What is the solution to the system of equations
(-2,4)
(3,4)
(4,-2)
(4,3)
Hey there! I'm happy to help!
When graphing a system of equations, the solution is the point where the two lines meet. We see that they intersect at (-2,4).
Therefore, the solution to the system of equations is (-2,4).
Have a wonderful day! :D
Answer:
A
Step-by-step explanation:
edge 2020 Dec 9
Lexie, a bowler, claims that her bowling score is more than 140 points, on average. Several of her teammates do not believe her, so she decides to do a hypothesis test, at a 5% significance level, to persuade them. She bowls 18 games. The mean score of the sample games is 155 points. Lexie knows from experience that the standard deviation for her bowling score is 17 points. H0: μ=140; Ha: μ>140 α=0.05 (significance level) What is the test statistic (z-score) of this one-mean hypothesis test, rounded to two decimal places?
Answer:
The test statistic is [tex]t = 3.744[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 140[/tex]
The The level of significance is [tex]\alpha = 0.05[/tex]
The sample size is n = 18
The null hypothesis is [tex]H_o : \mu = 140[/tex]
The alternative hypothesis is [tex]H_a : \mu > 140[/tex]
The sample mean is [tex]\= x = 155[/tex]
The standard deviation is [tex]\sigma = 17[/tex]
Generally the test statistics is mathematically represented as
[tex]t = \frac{\= x - \mu }{ \frac{ \sigma}{ \sqrt{n} } }[/tex]
substituting values
[tex]t = \frac{ 155 - 140 }{ \frac{ 17 }{ \sqrt{18} } }[/tex]
[tex]t = 3.744[/tex]
17) Suppose you will perform a test to determine whether there is sufficient evidence to support a
claim of a linear correlation between two variables. Find the critical value(s) of r given that
n = 10 and a = 0.05.
A) r= 10.666
B) r= +0.765
C) r= +0.632
D) r= 0.632
Answer: C. ±0.632.
Step-by-step explanation:
We have given,
Sample size : n= 10
Significance level : [tex]\alpha=0.05[/tex]
Test to check determine whether there is sufficient evidence to support a
claim of a linear correlation between two variables is a two tailed test.
Degree of freedom(df) = n- 2=8
Now , by the correlation coefficient(r) table ,
The critical r value corresponding to df = 8 and Significance level = 0.025 (0.05/2) is ±0.632.
Hence, the correct option is C. ±0.632.
