Answer:
40 or 16+6+6+6+6
Step-by-step explanation:
To find the surface area of a 3d figure, we can imagine all of its faces laid down on a flat plane. In this case, we would have a square, and four congruent triangles. Now all we have to do is find the areas of each shape and add them up.
4 is the base of the pyramid, so it's also the square's side length. Since a square has four equal sides, our square's length and width are both 4.
4*4 = 16
For every triangle we have, the base is 4 and the height is 3. The area of a triangle can be found using the formula A=(bh)/2. We plug in the values:
A = (4*3)/2
A = (12)/2
A = 6
Since we have 4 triangles, the surface area is:
16+6+6+6+6 = 40
Answer:
16+6+6+6+6
Step-by-step explanation:
KHan
please help ASAP. Which statement below is NOT true for the graph of a quadratic function? a) the axis of symmetry intersects the parabola at the vertex b) when the coefficient of x^2 is positive, the vertex of the parabola is a minimum point c)The vertex of a parabola is its highest or lowest level d) the parabola is symmetrical about the y-axis
Answer:
Step-by-step explanation:
All of these statements about a vertical parabola with known vertex are true.
The statement which is not always true about the graph of a quadratic function is option d) the parabola is symmetrical about the y-axis.
What is Parabola?A parabola is a open U shaped curve on a plane where all the points on the curve will be at an equal distance from a fixed point called focus and a fixed line called directrix.
Vertex of a parabola is the point where the parabola intersects with it's line of symmetry. So the vertex will always lie at the maximum point or the minimum point.
Axis of symmetry is the line that passes through the vertex of a parabola.
Graph of the quadratic equation will always be a parabola.
When the coefficient of x² is positive, then the vertex of the parabola will be at a minimum point and if the coefficient is negative, then the vertex will be at a maximum point.
The parabola is symmetrical to y axis only if the vertex of the parabola lies on the Y axis. So it will not be always true.
Hence the statement the parabola is symmetrical about the y-axis is not always true.
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The principal feature of the redesigned checks is a series of printed instructions that the company hopes will help merchants confirm a check’s authenticity, which includes reminders to watch the endorsement, compare signatures, and view the watermark while holding the check to the light.
(A) which includes reminders to watch the endorsement, compare signatures, and view
(B) which include reminders for watching the endorsement, to compare signatures and view
(C) by including reminders for watching the endorsement, comparing signatures, and viewing
(D) including reminders to watch the endorsement, comparing signatures and viewing
(E) including reminders to watch the endorsement, compare signatures, and view
Answer:
(E) including reminders to watch the endorsement, compare signatures, and view
Step-by-step explanation:
The principle features that will help the company to confirms checks authenticity. It include endorsements and compare the signatures with the designated signatories. If the signatures are matched correctly with the assigned signatories the check is hold in light to view the watermark on it.
The net profit in dollars per day for a small business owner is given by the equation f(x) = -0.1x^2 + 6 x + 4, where x is the number of employees he hires. If he hires the number of employees that will maximize his profit, what will his profit be in dollars per day? (Enter an exact number.) dollars per day
Answer:
[tex]\large \boxed{\sf \ \ \text{The maximum profit is \$94 per day.} \ \ }[/tex]
Step-by-step explanation:
Hello,
The coefficient in [tex]x^2[/tex] is negative.
So, there is a maximum at the vertex point which is
[tex]x=-\dfrac{b}{2a}==\dfrac{-6}{-0.2}=\dfrac{6}{0.2}=30[/tex]
And then the maximum is f(30)=
[tex]-0.1\cdot 30^2+6\cdot 30 +4=-90 +180+4=94[/tex]
So the maximum profit is 94 $ per day.
Hope this helps.
Do not hesitate if you need further explanation.
Thank you
17. Mary bought 10 quarts of juice at the
grocery. How many gallons of juice did
she buy?
A 1.4 gal
C 3.5 gal
B 2.5 gal
D 4.5 gal
Pls help
Answer:
B 2.5 Gal
Step-by-step explanation:
Answer:
I think the correct answer may be B.
Step-by-step explanation:
find the area of equilateral triangle whose median is X cm
options:
a.x^2
b.(x^2)/2
c.(x^2)/√3
d.(x^2)/3
Bob and Dan earned a total of $72
shoveling snow. If Bob earned 3 times as
much as Dan, how much did each boy
earn?
Answer:
see explanation
Step-by-step explanation:
If Dan earns $x then Bob earns $3x ( 3 times as much as Dan ), then
x + 3x = 72 , that is
4x = 72 ( divide both sides by 4 )
x = 18
Thus
Dan earns $18 and Bob earns 3 × $18 = $54
The earning of Bob will be 54 dollars and the earning of Dan will be 18 dollars.
What is the linear system?A linear system is one in which the parameter in the equation has a degree of one. It might have one, two, or even more variables.
Let the earning by Bob be x and the earning by Dan be y.
Bob and Dan earned a total of $72 shoveling snow. Then the equation will be
x + y = 72 ...1
If Bob earned 3 times as much as Dan. Then the equation will be
x = 3y ...2
Substitute the value of x in equation 1, then the equation will be
3y + y = 72
4y = 72
y = $18
Then the money earned by Bob will be
x = 3y
x = 3(18)
x = $54
Thus, the earning of Bob will be 54 dollars and the earning of Dan will be 18 dollars.
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Andrew's bicycle has tires with a radius of 7 inches. What is the area of one of the bicycle tires, in terms of π?
Answer:
49π
Step-by-step explanation:
The formula for the area of a circle is,
[tex]\pi r^2[/tex]
If the radius is 7 inches we need to plug that in for r in the formula.
π(7)^2
7*7 = 49
Thus,
the area in terms of pi is 49π.
Hope this helps :)
Answer:
49πStep-by-step explanation:
[tex]r = 7\\A = ?\\A =\pi r^2\\A =\pi7^2\\A = 49\pi[/tex]
Please Help! A pair of equations is shown below. x + y = 2 y = one halfx + 5 If the two equations are graphed, at what point do the lines representing the two equations intersect? (4, −2) (−2, 4) (2, 5) (5, −2)
Answer:
(-2,4)
Step-by-step explanation:
First, put x+y=2 into slope-intercept form: y=-x+2
Second, set the to equations equal to each other: -x+2=1/2x+5
Then, add x to both sides: -x+x+2=1/2x+x+5 to get: 2=3/2x+5
Next, subtract 5 from both sides: 2-5=3/2x+5-5, to get -3=3/2x
Finally, to get the x-value, divide both sides by 3/2: -3(2/3)=3/2x(2/3), to get x=-2
Lastly, substitute -2 for x into one of the equations to find y:
x+y=2
-2+y=2
add 2 to both sides: -2+2+y=2+2, to get y=4
The solution is (-2,4)
Answer:
(- 2, 4 )
Step-by-step explanation:
Given the 2 equations
x + y = 2 → (1)
y = [tex]\frac{1}{2}[/tex] x + 5 → (2)
Substitute y = [tex]\frac{1}{2}[/tex] x + 5 into (1)
x + [tex]\frac{1}{2}[/tex] x + 5 = 2 ( multiply through by 2 to clear the fraction )
2x + x + 10 = 4
3x + 10 = 4 ( subtract 10 from both sides )
3x = - 6 ( divide both sides by 3 )
x = - 2
Substitute x = - 2 into (1) and evaluate for y
- 2 + y = 2 ( add 2 to both sides )
y = 4
Solution is (- 2, 4 )
WILL GIVE BRANLIEST AND 20 POINTS!!
List the coordinates of FOUR vertices that create the feasible region on the graph. Submit your answer in the form of FOUR ordered Pairs (x, y)
Step-by-step explanation:
The coordinates of the feasible region are:(In clockwise direction)
(200, 200)
(300, 200)
(500, 0)
(300, 0)
8 7 12 7 11
10 7 12
Find:
a)the median
b) the range
c)the mode
Answer:
a) Median: 9
b) Range: 5
c) Mode: 7
Step-by-step explanation:
The median is the number in the middle.
First, you put the numbers in order: 7, 7, 7, 8, 10, 11, 12, 12
The middle of this is 8 and 10, so you plus them and divide by to 2, then it gives 9, so the median is 9.
To find the range, you minus the highest number and the lowest number, 12-7=5.
Mode is the most occurring and repetitive number, in this case, 7, because it is written 3 times.
Hope this helps!!!
Answer:
[tex]\boxed{\mathrm {Median = 9}}[/tex]
[tex]\boxed{\mathrm{Range = 5}}[/tex]
[tex]\boxed{\mathrm{Mode = 7}}[/tex]
Step-by-step explanation:
The observations are:
8,7,12,7,11,10,7,12
In ascending order:
=> 7,7,7,8,10,11,12,12
A) Median => Middlemost no.
Median = 8,10
=> [tex]\frac{8+10}{2}[/tex]
=> [tex]\frac{18}{2}[/tex]
Median = 9
B) Range = Highest No. = Lowest No.
RANGE = 12-7
Range = 5
C) Mode => frequently occurring number
Mode = 7
How many triangles does a=6 b=10 A=33° create?
Answer:
2 triangles are possible.
Step-by-step explanation:
Given
a=6
b=10
[tex]\angle[/tex]A=33°
To find:
Number of triangles possible ?
Solution:
First of all, let us use the sine rule:
As per Sine Rule:
[tex]\dfrac{a}{sinA}=\dfrac{b}{sinB}[/tex]
And let us find the angle B.
[tex]\dfrac{6}{sin33}=\dfrac{10}{sinB}\\sinB = \dfrac{10}{6}\times sin33\\B =sin^{-1}(1.67 \times 0.545)\\B =sin^{-1}(0.9095) =65.44^\circ[/tex]
This value is in the 1st quadrant i.e. acute angle.
One more value for B is possible in the 2nd quadrant i.e. obtuse angle which is: 180 - 65.44 = [tex]114.56^\circ[/tex]
For the value of [tex]\angle B = 65.44^\circ[/tex], let us find [tex]\angle C[/tex]:
[tex]\angle A+\angle B+\angle C = 180^\circ\\\Rightarrow 33+65.44+\angle C = 180\\\Rightarrow \angle C = 180-98.44 = 81.56^\circ[/tex]
Let us find side c using sine rule again:
[tex]\dfrac{6}{sin33}=\dfrac{c}{sin81.56^\circ}\\\Rightarrow c = 11.02 \times sin81.56^\circ = 10.89[/tex]
So, one possible triangle is:
a = 6, b = 10, c = 10.89
[tex]\angle[/tex]A=33°, [tex]\angle[/tex]A=65.44°, [tex]\angle[/tex]C=81.56°
For the value of [tex]\angle B =[/tex][tex]114.56^\circ[/tex], let us find [tex]\angle C[/tex]:
[tex]\angle A+\angle B+\angle C = 180^\circ\\\Rightarrow 33+114.56+\angle C = 180\\\Rightarrow \angle C = 180-147.56 = 32.44^\circ[/tex]
Let us find side c using sine rule again:
[tex]\dfrac{6}{sin33}=\dfrac{c}{sin32.44^\circ}\\\Rightarrow c = 11.02 \times sin32.44^\circ = 5.91[/tex]
So, second possible triangle is:
a = 6, b = 10, c = 5.91
[tex]\angle[/tex]A=33°, [tex]\angle[/tex]A=114.56°, [tex]\angle[/tex]C=32.44°
So, answer is : 2 triangles are possible.
Which is the graph of f(x) = (x - 1)(x + 4)?
4
2
2.
2
4
B
-6
2
X
-2
8
-6
Ty
6
2
Answer:
Its the last option. On the bottom.
Step-by-step explanation:
You need to Solve for x to find the zeroes of the equation.
x-1=0 So one x is at 1.
x+4=0 So the other x is at -4.
This graph is also not negative so it does not get flipped across the x-axis
The graph of the function [tex]f(x) = (x - 1)(x + 4)[/tex] is graph (d)
How to determine the graphThe equation of the function is given as:
[tex]f(x) = (x - 1)(x + 4)[/tex]
From the above function, we have the zeros of the function to be:
1 and -4
This means that:
The graph of the function passes through the x-axis at x =1 and x = -4The graph opens upwardHence, the graph is graph (d)
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What is the value of x
Answer:
4
Step-by-step explanation:
For the first triangle which is triangle <KJL
Hypotenuse= 8✓2
Angle=30°
Opposite = ?
Therefore we will use Sine formula
Sin30° = Y/8✓2
Y=4✓2
For the second triangle which is triangle <JML
Hypotenuse= 4✓2
Opposite=X
Angle=45°
Therefore we will use Sine formula again
Sin45°=X/4✓2
X=4
Answer:
x = 4Step-by-step explanation:
ΔJKL is half of equilateral triangle and ΔJML is half of square.
We can use properties of these triangles (picture):
m∠KJL=90° and m∠JKL = 30° ⇒ JL = 0.5KL = 0.5•8√2 = 4√2
m∠JML=90° and m∠MJL = 45° ⇒ JL = ML√2
4√2 = x√2
x = 4
Nine-banded armadillos always give birth to quadruplets—four identical babies (called pups). Jenny’s armadillo has produced four female pups. Jenny realizes that each of those pups could eventually have four more armadillos.
a. How many armadillos would Jenny have if the four pups grew up to have four more pups each?
b. What if every generation of Jenny’s armadillos was female? How many armadillos would there be if you only count the ones in the 5th generation? Can you write a formula for the number of armadillos in any given generation? Please explain what each variable and each number in your formula means.
c. According to this formula the world should be overrun with armadillos after 20 to 25 generations. Why isn’t this true in real life?
Answer:
a. 16; b. aₙ = 4ⁿ⁻¹; c. predation and carrying capacity will limit the population
Step-by-step explanation:
a. The first female had 4 pups.
If each of them had 4 pups, there would be 4 × 4 = 4² = 16 pups.
b. 1st generation = 1 pup
2nd generation = 4 × 1 pup = 4 pups
3rd generation = 4 × 4 pups = 16 pups
4th generation = 4 × 16 pups = 64 pups
5th generation = 4 × 64 pups = 256 pups
The sequence is 1, 4, 16, 64, 256, …
We can also write it as 4⁰, 4¹, 4², 4³, 4⁴, …
Note that the exponent is one less than the number of the generation.
Thus, the general formula for the nth term, aₙ, is
aₙ = 4ⁿ⁻¹, where
n = the number of the generation
a = the number of pups in that generation.
c. a₂₅ = 4²⁵⁻¹ = 4²⁴ ≈ 281 000 000 000 000 or 281 trillion
The population would not reach that number because there would not be enough food for all those pups. Pups would die of starvation until their numbers equalled the carrying capacity of the ecosystem and would level off at that point.
There would also be increased predation by coyotes, bobcats, etc. This would also keep the population growth in check,
Which relation is a function of x? {(1, 2), (7, 6), (3, 2), (1, 0), (5, 6)} A 2-column table with 4 rows. Column 1 is labeled x with entries 0, 0, 0, 0. Column 2 is labeled y with entries 2, negative 6, 9, negative 7. x = 3 y squared minus 7 On a coordinate plane, a graph curves up, then curves down, and then curves up again. please comment i cant see answers thank you! :)
Answer: The answer is D . The graph
Step-by-step explanation: It was the answer given on Edge.
Answer:
d
Step-by-step explanation:
An oblique cone has a height equal to the diameter of the base. The volume of the cone is equal to 18π cubic units.
An oblique cone has a diameter of 2 x and a height of 2 x. The volume of the cone is 18 pi cubic units.
What is the radius of the cone?
Answer:
3
Step-by-step explanation:
plug in the values in the formula of volume of cone
18pi=pi(x^2)(2x)(1/3)
then solve for x
multiply both sides by 3 : 54pi = pi(x^2)(2x)
divide pi from both sides : 54 = (x^2)(2x)
divide 2 from both sides : 27 = x^3
cube root of both sides : 3 = x
Answer: 3
Step-by-step explanation:
edg 2020
A chef uses 12 cup of cheese for a small pizza. There are 6 grams of fat in 14 cup of cheese. Drag one expression next to each question. The correct expression for each row is a way to answer that question.
Answer:
I guess that we want to find how many grams of fat we have in a small pizza.
In a small pizza, we use 12 cups of cheese.
in 14 cups of cheese, we have 6 grams of fat.
Then, in 12 cups of cheese, we have x grams of fat.
We want to find the value of x.
We know that the ratio between the number of cups must be the same as the ratio between the grams of fat then:
12cups/14cups = x/6grams
x = (12/14)*6grams = 5.14 grams
Then in the 12 cups of cheese, we have 5.14 grams of fat.
Help me please
I’m having so much trouble
Answer:
Step-by-step explanation:
5 * 45 = 225
225+75=300
300/500=0.6
The tank will be 60% full.
If this helped, make sure to mark it as brainliest :D
Answer:
C.60%
Step-by-step explanation:
45 x 5 = 225 225 + 75 = 300
300 / 500 = 0.6 = 60%
The stock of Company A lost 2.75% today to $77.80. What was the opening price of the stock in the beginning of the day?
Answer:
$80
Step-by-step explanation: $80.00*.0275= 2.20 80.-2.20=$77.80
The opening price of the stock in the beginning is A = $ 80
What is Percentage?A percentage is a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign, %
The difference between an exact value and an approximation to it is the approximation error in a data value. Either an absolute error or a relative error might be used to describe this error.
Percentage change is the difference between the measured value and the true value , as a percentage of the true value
Percentage change =( (| Measured Value - True Value |) / True Value ) x 100
Given data ,
Let the opening price of the stock in the beginning be A
Now , the percentage of decrease in the stock price = 2.75 %
And , the price after decrease = $ 77.80
On simplifying , we get
The opening price of the stock in the beginning - ( percentage of decrease in the stock price ) x opening price of the stock in the beginning = $ 77.80
A - ( 2.75 / 100 )A = 77.80
( 97.25/100 )A = 77.80
Divide by 97.25 on both sides , we get
A / 100 = 0.8
Multiply by 100 on both sides , we get
A = $ 80
Hence , the opening price of the stock is A = $ 80
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Triangles ABC and EDC are outlined on a bridge. The triangles share vertex C and angles D and B are right angles. A new bridge structure requires triangles that are in a ratio of 1:1. If AC = 5x − 5 and EC = 3x + 9, find the distance between the top and bottom of the bridge, in feet.
CHECK THE ATTACHED FIQURE FOR THE BRIDGE
Answer:
60 ft
Step-by-step explanation:
From the question we know that triangles ABC and EDC are in a 1:1 with this given ratio it implies that
triangles ABC and EDC are congruent then we can say
side EC = side AC
3x + 9 = 5x - 5
Then we can simplify to know value of x
3x + 14= 5x
2x = 14
x = 7
But we know that AC= 5x - 5 , then substitute value of x into it
AC = 5x + 5 = 5(7) - 5
= 35 - 5
AC= 30 ft
Also EC= 3x + 9 then substitute value of x into it
EC = 3x + 9 = 3(7) + 9
= 21 + 9
EC= 30 ft
Then the the distance between the top and bottom of the bridge, in feet, = EC+AC
= 30 + 30 = 60 ft
Answer:
60 ft
Step-by-step explanation:
i did the test
Please give me correct answer and fast answer it if know answer only
Answer:
Approximatley 5.8 units.
Step-by-step explanation:
We are given two angles, ∠S and ∠T, and the side opposite to ∠T. We need to find the unknown side opposite to ∠S. Therefore, we can use the Law of Sines. The Law of Sines states that:
[tex]\frac{\sin(A)}{a}=\frac{\sin(B)}{b} =\frac{\sin(C)}{c}[/tex]
Replacing them with the respective variables, we have:
[tex]\frac{\sin(S)}{s} =\frac{\sin(T)}{t} =\frac{\sin(R)}{r}[/tex]
Plug in what we know. 20° for ∠S, 17° for ∠T, and 5 for t. Ignore the third term:
[tex]\frac{\sin(20)}{s}=\frac{\\sin(17)}{5}[/tex]
Solve for s, the unknown side. Cross multiply:
[tex]\frac{\sin(20)}{s}=\frac{\sin(17)}{5}\\5\sin(20)=s\sin(17)\\s=\frac{5\sin(20)}{\sin(17)} \\s\approx5.8491\approx5.8[/tex]
Read the following word problem, then choose which linear equation models the problem.
One number is 10 times another number. Their difference is 54. Find the numbers.
A. x(x) - 10 = 54
B. 10x - x = 54
C. 10x + x = 54
D. 10x(x) = 54
c) Bhurashi can do 1/3 part of a work in 6 days.
(1) In how many days would she complete the whole work?
(ii) How much work does she do in 1 day?
m) How much work is left to do if she worked only for 9 days?
Answer:
i. 18 daysii.[tex] \frac{1}{18} [/tex] part of workiii. [tex] \frac{1}{2} [/tex] part of workStep-by-step explanation:
i.
[tex] \frac{1}{3} [/tex] part of work can be done in 6 days.
Days taken to complete the whole work:
= 6 * 3
= 18 days
ii. Whole work will be done in 18 days.
So, 1 day work = [tex] \frac{1}{18} [/tex]
iii. Work done in 9 days :
[tex] \frac{1}{18} \times 9 [/tex]
[tex] = \frac{1}{2} [/tex]
So, remaining work :
[tex]1 - \frac{1}{2} [/tex]
[tex] = \frac{1 \times 2 - 1}{2} [/tex]
[tex] = \frac{2 - 1}{2} [/tex]
[tex] = \frac{1}{2} [/tex] part of work
Hope this helps...
Good luck on your assignment..
Find the product. (5p + 2)2^
Answer:
25p^2 + 4 + 20p
Step-by-step explanation:
(5p + 2)^2 = (5p)^2 + (2)^2 + 2 × 5p × 2
= 25p^2 + 4 + 20p
Drew likes to take the long way to school each morning. He walks 3 blocks west and then 3 blocks north to arrive at the school. Today he is running late and decides go directly to school to save time. (Assume there is nothing obstructing his path.) If one block is 310 feet, how many feet will he travel if he goes directly to school? Round to the nearest tenth of a foot.
Answer:
Distance travel by Drew = 1,315.21 feet (Approx)
Step-by-step explanation:
Given:
Total block in north = 3
Total block in west = 3
1 block = 310 feet
Find:
Distance travel by Drew
Computation:
Total distance in north = 3 × 310 = 930 feet
Total distance in west = 3 × 310 = 930 feet
Distance travel by Drew = √Total distance in north² + Total distance in west²
Distance travel by Drew = √930² + 930²
Distance travel by Drew = √864,900 + 864,900
Distance travel by Drew = √1,729,800
Distance travel by Drew = 1,315.21 feet (Approx)
A smaller number is 3 less than half a larger number. The larger number is 10 times 1 less than the smaller number. Let x represent the smaller number, and let y represent the larger number. Which equations can be used to model the situation? Check all that apply. x = one-half y minus 3 2 x minus y = negative 6 2 x minus y = negative 3 x = one-half (y minus 3) y = 10 (x minus 1)
Answer: x=one-half y minus
Step-by-step explanation:
Answer:
x=1/2 y-3
Step-by-step explanation:
Solve x2 + 4x − 4 = 0
Answer Choices:
x = -2 ± √16 all over 2
x = -4 ± √2
x = -2 ± 2 √2
x = 4 ± √18 all over 2
Answer:
third option
Step-by-step explanation:
Given
x² + 4x - 4 = 0 ( add 4 to both sides )
x² + 4x = 4
Using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 4 + 4, that is
(x + 2)² = 8 ( take the square root of both sides )
x + 2 = ± [tex]\sqrt{8}[/tex] = ± 2[tex]\sqrt{2}[/tex] ( subtract 2 from both sides )
x = - 2 ± 2[tex]\sqrt{2}[/tex]
The number of people contacted at each level of a phone tree can be represented by f(x) = 3^x where x represents the level.
What is x when f(x) = 27?
A. X = 2; At level 2, 27 people will be contacted.
B. x = 24; At level 24, 27 people will be contacted.
C. x = 3; At level 3, 27 people will be contacted.
D. x = 9; At level 9,27 people will be contacted.
Answer:
3
Step-by-step explanation:
Answer:
c is the correct answer
Step-by-step explanation:
how many unique planes can be determined by four noncoplanar points?
Answer:
Four unique planes
Step-by-step explanation:
Given that the points are non co-planar, triangular planes can be formed by the joining of three points
The points will therefore appear to be at the corners of a triangular pyramid or tetrahedron such that together the four points will form a three dimensional figure bounded by triangular planes
The number of triangular planes that can therefore be formed is given by the combination of four objects taking three at a time as follows;
₄C₃ = 4!/(3!×(4-3)! = 4
Which gives four possible unique planes.
An airline company advertises that 100% of their flights are on time after checking 5 flights from yesterday and finding that these 5 were on time.
a) What is population of interest?
b) What is the sample?
c) Was this a representative sample? Explain.
d) How should the company determine the percentage of their flights that are on time?
Answer with explanation:
Given: An airline company advertises that 100% of their flights are on time after checking 5 flights from yesterday and finding that these 5 were on time.
a) population: A large group of observations have characteristics related to the point of the study.
Here, population: "All flights operated by the company"
b) Sample: It is a subset of the population.
Here, Sample: "5 flights from yesterday"
(c)
Since the number of flights per day operated by an airline company is much larger than 5 ( generally in hundreds).
i.e. the sample is too small to be able to assure that the results are true.
Hence, this is not a representative sample.
(d) To determine the percentage of their flights that are on time we use the following formula:
(Number of flights are on time) ÷ (Total flights) x 100