Rob sent an email survey to 2,000 cell phone owners asking about their satisfaction with their current plan. Only 256 people returned the survey and they were predominately 18-24 years old.

Which of the following statements is true?


Rob is ignoring the assumption that all survey participants will want to act independently.


The survey likely has bias because the people who could not answer differ from those who did answer.


Rob included too many people on the survey list, affecting the data collected.


The survey suffers from census issues because only 256 people responded.

Answers

Answer 1

Answer:

option B

everyone has different opinions about different things, since we only recorded the survey of a fourth of the total people, the survey will definitely have bias since the people who dont have to answer survey will not be able to record their opinions


Related Questions

The equation of a circle centered at the origin with a radius of unit length is x2 + y2 = 1. This equation changes if the center of the circle is not located at the origin or the radius is not of unit length.

Answers

Answer:

The equation for a unit radius circle, centered at the origin is:

x^2 + y^2 = 1

Now, if we want to move it horizontally, you can recall to the horizontal translations:

f(x) -----> f(x - a)

Moves the graph to the right by "a" units.

A vertical translation is similar.

Then, if we want a circle centered in the point (a, b) we have:

(x - a)^2  + (y - b)^2 = 1.

Now, if you want to change the radius, we can actually write the unit circle as:

x^2 + y^2 = 1^2

Where if we set x = 0, 1 = y, this is our radius

So if we have:

x^2 + y^2 = R^2

And we set the value of x = 0, then R = y.

So our radius is R.

Then:

"A circle of radius R, centered in the point (a, b) is written as:

(x - a)^2 + (y - b)^2 = R^2

The cost of performance tickets and beverages for a family of four can be modeled using the equation 4x+12=48,where x represents the cost of a. Ticket.how much is one ticket

Answers

Answer:

x=9; one ticket is $9

Step-by-step explanation:

4x+12=48

4x=48-12

4x=36

x=36/4

x=9

Solve this system of equations:

3x - 2y = -8
y=3/2x - 2

PLEASE WRITE THE STEPS

Answers

Hey there! I'm happy to help!

We see that y is equal to 3/2x-2. We can replace the y in the first equation with 3/2x-2 because they are equal and we can solve for x.

3x-2(3/2x-2)=-8

We use the distributive property to undo the parentheses.

3x-3x+4=-8

We combine like terms.

4=-8

We see that since there is no x anymore, there cannot be a solution. We have no x value to solve for the y value either, so there is no solution to this system of equations.

Have a wonderful day! :D

simplify the expression 10 divided by 5 times 3

Answers

Answer:

= 2/3

Step-by-step explanation:

10 / (5*3)

= 10/15

= 2/3

What is numbers 1-30 added all together

Answers

Answer:

465

Step-by-step explanation:

The sum of consecutive numbers has a formula, and it's

[tex]\frac{n(n+1)}{2}[/tex].

Where n is the amount of numbers.

From 1-30, it's 30 numbers, so:

[tex]\frac{30(30+1)}{2} \\\\\frac{30(31)}{2} \\\\\frac{930)}{2} \\\\\\465[/tex]

Hope this helped!

The numbers 1-30 added together is 465

What faction of a day is 5hrs 20 mine​

Answers

Answer:

16/3 hours  5 1/3

Step-by-step explanation:

Answer: 5 1/3

Step-by-step explanation:

use the product of powers property to simplify the numeric expression.

4 1/3 • 4 1/5 = _____

Answers

Answer:

The value of [tex]4^{\dfrac{1}{3}} {\cdot} 4^{\dfrac{1}{5}[/tex]  is  [tex]4^{\dfrac{8}{15}}[/tex] .

Step-by-step explanation:

We need to simplify the numeric expression using property. The expression is as follows :

[tex]4^{\dfrac{1}{3}} {\cdot} 4^{\dfrac{1}{5}[/tex]

The property to be used is : [tex]x^a{\cdot} x^b=x^{a+b}[/tex]

This property is valid if the base is same. Here, base is x.

In this given problem, x = 4, a = 1/3 and b = 1/5

So,

[tex]4^{\dfrac{1}{3}} {\cdot} 4^{\dfrac{1}{5}}=4^{\dfrac{1}{3}+\dfrac{1}{5}}\\\\=4^{\dfrac{5+3}{15}}\\\\=4^{\dfrac{8}{15}}[/tex]

So, the value of [tex]4^{\dfrac{1}{3}} {\cdot} 4^{\dfrac{1}{5}[/tex]  is  [tex]4^{\dfrac{8}{15}}[/tex] .

Stepwise regression is a variable screening method, not a model building method.
A. True
B. False

Answers

Answer:

A. True

Step-by-step explanation:

Stepwise regression is a variable-selection method for independent variables.

Stepwise regression  helps us to recognize and choose the most handy descriptive variables from a list of several reasonable independent variables.

It entails a series of steps that is drafted to locate the most handy X-variable to incorporate in a regression model. During each step of the course of action or method, each X - variable is estimated by applying a set criterion to determine if it is meant to exist in the model.

The basis for selection can be choosing a variable which satisfies the stipulated criterion or removing a variable that least satisfies the criterion. A typical illustration of such criterion is the t value.

Perimeter =68 Length (L) is 4 less than twice the width (W)

Answers

Answer:

Length = 21.3333333333;   Width: 12.6666666667

Step-by-step explanation:

Perimeter = 68

Perimeter of a rectangle:

2 (L +W)

Length (L) = 2W - 4

Width = W

2 ( 2W -4 +W) = 68

=> 2 (3W - 4) = 68

=> 6w -8 = 68

=> 6w = 76

=> w = 12.6666666667

Length = (12.6666666667 X 2) - 4

=> 21.3333333333

WILL GIVE BRAINILY 5 STARS AND THANKS FOR CORRECT ANSWERLenora wants to buy granola bars for her hiking trip. Eight bars cost $2.40. She wants to buy 12 bars. How much will 12 bars cost?

Answers

Answer:

$3.60

Step-by-step explanation:

2.40/8=.30

$.30 per bar

.3 x 12= $3.60

Answer:

$3.60

Step-by-step explanation:

Proportions

8 bars ⇔ $2.4

12 bars ⇔ $W

W = 12*2.4/8

W = $3.6

Using minutes as the unit of measurement on the left-hand side of a constraint and using hours on the right-hand side is acceptable since both are a measure of time.

a. True
b. False

Answers

Answer:

True

Step-by-step explanation:

Name one real-world object that suggests A. Points B. Lines and C. Planes

Answers

There are many examples to pick from, one is

point = location on map

line = straight road between two locations (aka two points)

plane = flat ground (the ground cannot have any hills or valleys)

First, let's write some useful definitions:

Point: it is an entity that has a location in a given space or plane, and do not have any surface nor measure.

Line: if we have two points, we can define a line as a straight, infinite ray that connects them. Still does not have a surface

Plane: We can define a plane as a line and a point outside of it, here appears the concept of the surface.

So, the easier one is a plane, a sheet of paper could be a good representation of a plane. And in the same way that a sheet of paper can bend in different ways, also do the planes.

For the line, we could use a really straight wire.

Finally, the point, which is the hardest one to describe (notice that we used points to describe the other two, lines, and planes) so here we could choose something small, that has near to no surface and that also has a location in the space. An example of this could be an electron or any other elemental particle.

If you want to learn more, you can read:

https://brainly.com/question/17213603

The upper-left coordinates on a rectangle are (-1,4), and the upper-right coordinates are (3,4). The rectangle
has a perimeter of 24 units.
Draw the rectangle on the coordinate plane below.

Answers

Answer:

Step-by-step explanation:

Note that the perimeter of a rectangle P = 2(Length + Breadth)

The distance between the upper-left coordinates on a rectangle and the upper-right coordinates is the breadth of the rectangle. To get the breadth of the rectangle, we will use tgw formula for calculating the distance between two points as shown.

D = √(y2-y1)²+(x2-x1)²

Given the coordinates (-1,4) and (3,4), the distance between the coordinates where x1 = -1, y1 = 4, x2 = 3 and y2 = 4 will be expressed as.

B = √(4-4)²+(3-(-1))²

B = √0+4²

B = √16

B = 4

Hence the breadth of the rectangle is 4 units.

Substituting the breadth into the formula for calculating the perimeter will give;

P = 2(L+B)

24 = 2(L+4)

L+4 = 24/2

L+4 =12

L = 12-4

L = 8

Hence the length of the rectangle is 8 units.

The diagram of the rectangle on a coordinate is as given in the attachment below.

Suppose that y varies directly with x and y=20 when x=2 Find y when x=8

Answers

Answer:

80

Step-by-step explanation:

x      y

2 = 20

8 = x

cross multiply( 8*20)/2

= 4 * 20

= 80

A hunter shot 7 ducks. The hunter's dog recovered 5/7 of the ducks. How many ducks were recover

Answers

Answer:

5

Step-by-step explanation:

Just multiply 5/7 by 7 since his dog retrieved 5/7 out of the 7 ducks he shot.

Answer:

5

Step-by-step explanation:

7*5/7

7 represents the # of ducks

5/7 represents the # of ducks that were recovered

The question asks the number of ducks that were recovered so you should multiply the total # of ducks there are by the fraction that were recovered.

WHY CAN'T ANYONE HELP ME PLEASE?A ​40% solution of fertilizer is to be mixed with a ​80% solution of fertilizer in order to get 80 gallons of a ​70% solution. How many gallons of the ​40% solution and ​80% solution should be​ mixed? 40% solution =? gallons, 80% solution =? gallons

Answers

Answer:

40% solution = 20 gallons

80% solution = 60 gallons

Step-by-step explanation:

x = gallons of 40% solution

y = gallons of 80% solution

Total volume is:

x + y = 80

Total amount of fertilizer is:

0.40 x + 0.80 y = 0.70 (80)

Solve by substitution.

0.40 x + 0.80 (80 − x) = 0.70 (80)

0.40 x + 64 − 0.80 x = 56

0.40 x = 8

x = 20

y = 60

what are the next terms in the number pattern -11, -8, -5, -2, 1

Answers

Answer:

4, 7, 10, 13

Step-by-step explanation:

Hey there!

Well in the given pattern,

-11, -8, -5, -2, 1

we can conclude that the pattern is +3 every time.

-11 + 3 = -8

-8 + 3 = -5

-5 + 3 = -2

-2 + 3 = 1

And so on

4, 7, 10, 13

Hope this helps :)

slope of -4/3x with point (7,20) find equation

Answers

Answer:

y= -4/3x+10 2/3

Step-by-step explanation:

To do this, just put the equation in point slope form and then rearrange it to y=mx+b, or slope intercept form. Slope point form is arranged like this, y-y1=m(x-x1). Now, just insert in the variables (x1=x coordinate of point, y1= y coordinate of point, m=slope). So your equation is now y-20=-4/3(x-7), which simplifies to y-20=-4/3x-9 1/3. Now rearrange it so that y in by itself, and all like terms are combined, making it look like this: y=-4/3x+10 2/3. Now its in slope intercept form and you've got your answer.

I hope my explanation wasn't confusing and that my answer helped.

A buoy floating in the sea is bobbing in simple harmonic motion with amplitude 13 in and period 0.25 seconds. Its displacement d from sea level at time t=0 seconds is 0in, and initially it moves downward. (Note that downward is the negative direction.)Required:Give the equation modeling the displacement d as a function of time t.

Answers

Answer:

The equation is [tex]x(t) = -13 cos (8 \pi t )[/tex]

Step-by-step explanation:

From the question we are told that

      The  amplitude is  [tex]A = 13 \ in[/tex]

       The period is  [tex]T = 0.25[/tex]

Generally the displacement function for a simple harmonic motion is mathematically represented as

        [tex]x(t) = A cos (wt )[/tex]

Here  [tex]w[/tex] is the angular frequency which is mathematically represented as

          [tex]w = \frac{2 \pi }{T}[/tex]

substituting values

          [tex]w = \frac{2 \pi }{ 0.25}[/tex]

          [tex]w = 8\pi[/tex]

Given that at t =  0  the displacement is equal to 0 it means that there is no phase shift and also  we are told that it is initially moving downward which implies that its Amplitude is  [tex]A = -13\ in[/tex]

So the equation modeling the displacement d as a function of time t is mathematically represented as

          [tex]x(t) = -13 cos (8 \pi t )[/tex]

Match each function name with its equation.

Answers

Answer:

a. Quadratic--[tex]y=x^{2}[/tex]

b. Absolute Value--[tex]y=|x|[/tex]

c. Linear--[tex]y=x[/tex]

d. Reciprocal Squared--[tex]y=\frac{1}{x^{2} }[/tex]

e. Cubic--[tex]y=x^{3}[/tex]

f. Square Root--[tex]y=\sqrt{x}[/tex]

g. Reciprocal--[tex]y=\frac{1}{x}[/tex]

h. Cube root--[tex]y=\sqrt[3]{x}[/tex]

Answer:

Step-by-step explanation:

y=[tex]x^{2}[/tex] is quadratic

y=x  is an absolute value

y= |x| os linear

y= [tex]\frac{1}{x}[/tex] is reciprocal

y= [tex]x^{3}[/tex] is cubic

y= [tex]\sqrt{x}[/tex] is square root

y= [tex]\frac{1}{x^{2} }[/tex] is reciprocal squared

y= [tex]\sqrt[3]{x}[/tex] is cube root

Excel:In cell B13, create a formula using the VLOOKUP function that looks up the value from cell A11 in the range A5:B7, returns the value in column 2, and specifies an exact match.

Answers

Answer:

=Vlookup'B13' A11' 7'false

Press enter.

Step-by-step explanation:

Vlookup is a technique in excel which enables users to search for criterion values. It is vertical lookup function in excel which return a value from a different column. The formula for Vlookup function is:

=Vlookup'select cell you want to look up in' select cell you want to lookup from' select column index number' true/false.

where true is approximate match and false is exact match.

Answer:=VLOOKUP(J2,A2:G23,2,FALSE)

Step-by-step explanation:

a. In cell J3, begin to enter a formula using the VLOOKUP function.

b. Use the Project ID (cell J2) as the lookup value.

c. Use the Projects table (range A2:G23) as the table_array.

d. Use the Project Name column (column 2) as the col_index_num.

e. Specify an exact match (FALSE) for the range_lookup.

The energy E (in ergs) released by an earthquake is approximated by log E= 11.8 + 1.5M. Where M is the magnitude of the earthquake. What is the energy released by the 1906 San Francisco quake, which measured 8.3 on the Richter scale? This energy, it is estimated, would be sufficient to provide the entire world's food requirements for a day. Answer in ergs.

Answers

Answer:

[tex]\large \boxed{3.4 \times 10^{10}\text{ ergs }}[/tex]

Step-by-step explanation:

[tex]\begin{array}{rcl}\log E & = & 11.8 + 1.5M\\& = & 11.8 + 1.5 \times 8.3\\& = & 11.8 + 12.45\\& = & 24.25\\E & = & e^{24.25}\\& = & \mathbf{3.4 \times 10^{10}} \textbf{ ergs}\\\end{array}\\\text{ The energy released was $\large \boxed{\mathbf{3.4 \times 10^{10}}\textbf{ ergs }}$}[/tex]

Yiadom is y
years now.
What would be
his age in the next ten
years.

Answers

Answer:

(y+10 ) years

Step-by-step explanation:

If Yiadom is y  years now.

Then after 10 years, his anew age will be = (y+10) yrs

Emily thinks the perfect tomato sauce has 8 cloves of garlic in every 500 mL, of sauce. Raphael's tomato sauce has 121 cloves of garlic in every 900 mL of sauce. What will Emily think of Raphael's tomato sauce? Choose 1 answer: Choose 1 answer: (Choice A) A It is too garlicky. (Choice B) B It is not garlicky enough. (Choice C) C It is perfect.

Answers

Answer:

A

Step-by-step explanation:

Let's find the ml per garlic for each sauce. Emily's has 1 clove of garlic for 62.5 ml. Raphael's has 1 clove of garlic for 7.438... ml. So, A, it will be too garlicky.

PLEASE HELP!!!!!! TIMED QUESTION!!!! FIRST CORRECT ANSWER WILL GET BRAINLIEST....PLEASE ANSWER NOW!!!!

The bar graph shows the number of students who earned each letter grade on an
exam, which statement about the graph is true?

1)
1/5 of the students earned a C
2)
3% more students earned an A then B
3)
20% of the students earned a D
4)
1/4 of the class earned a B​

Answers

Answer:

3)  20% of the students earned a D

Step-by-step explanation:

9 students got a D.

5 students got a C.

14 students got a B.

17 students got an A.

Total number of students:

9 + 5 + 14 + 17 = 45

1)  1/5 of the students earned a C

1/5 of 45 = 9

5 students got a C

False

2) 3% more students earned an A then B

3 more students got an A than a B, but not 3%.

False

3)  20% of the students earned a D

20% of 45 = 9

9 students got a D.

True

4)  1/4 of the class earned a B​

1/4 of 45 = 11.25

There were 14 B's.

False

Answer: 3)  20% of the students earned a D

Help please I need help as soon as possible!all answers are appreciated! Keisha tried to evaluate an expression step by step. 3+(−4)−7

Answers

Answer:

D no mistakes

Step-by-step explanation:

3+(-4)-7 is equal to 3-4-7=-8

Answer:0

Step-by-step explanation:

3+(-4)-7 when there are parenthesis around a negative number you flip it to positive and then 4+3-7=0

write 32 1/2 in radical form​

Answers

Answer:

Nothing further, the simplest answer is 32 1/2

Step-by-step explanation:

How much would you need to deposit in an account now in order to have $6,000 in the account in 8 years? Assume the account earns 6% interest compounded monthly. (could anyone do this whole problem out?

Answers

Answer:

$3,717

Step-by-step explanation:

Hello, in 1 year there are 12 months.

Let's note I the Initial amount.

So, after 1 month we will get the following, because we compute the interest amount for one month only.

I * ( 1 + 6% * (1/12) )

And the next month, we will have interest of the amount available from previous month so it gives

[tex]I * ( 1+6\% * \dfrac{1}{12} ) * ( 1+6\% * \dfrac{1}{12} ) \\\\=I*(1+\dfrac{6}{12*100})^2\\\\=I*(1+\dfrac{1}{200})^2\\\\=I*(1.005)^2[/tex]

... and after n months ...

[tex]I*(1.005)^n[/tex]

8 years is 8*12 = 96 months. so we are looking for I such that

[tex]I*(1.005)^{96}=6000\\\\<=> I =\dfrac{6000}{1.005^{96}}\\\\=\boxed{3717.14345....}[/tex]

Thank you.

What are the solutions to the system of equations? {y=2x2−8x+5y=x−2 (3.5, 0.5) and (1, −1) (7, 5) and (0.5, −1.5) (3.5, 1.5) and (1, −1) (3.5, 1.5) and (−1, −3)

Answers

Answer:

[tex](1,-1)[/tex] and [tex](3.5,1.5)[/tex]

Step-by-step explanation:

Given

[tex]y = 2x^2 - 8x+5[/tex]

[tex]y = x - 2[/tex]

Required

Determine the solution

Substitute x - 2 for y in [tex]y = 2x^2 - 8x+5[/tex]

[tex]x - 2 = 2x^2 - 8x+5[/tex]

Collect like terms

[tex]0 = 2x^2 - 8x - x + 5 + 2[/tex]

[tex]0 = 2x^2 - 9x + 7[/tex]

Expand the expression

[tex]0 = 2x^2 - 7x - 2x+ 7[/tex]

Factorize

[tex]0 = x(2x - 7) -1(2x - 7)[/tex]

[tex]0 = (x-1)(2x - 7)[/tex]

Split the expression

[tex]x - 1 = 0[/tex] or [tex]2x - 7 = 0[/tex]

Solve for x in both cases

[tex]x = 1[/tex] or [tex]2x = 7[/tex]

[tex]x = 1[/tex] or [tex]2x/2 = 7/2[/tex]

[tex]x = 1[/tex] or [tex]x = 3.5[/tex]

Recall that

[tex]y = x - 2[/tex]

When [tex]x = 1[/tex]

[tex]y = 1 -2[/tex]

[tex]y = -1[/tex]

When [tex]x = 3.5[/tex]

[tex]y = 3.5 - 2[/tex]

[tex]y = 1.5[/tex]

Hence, the solution is;

[tex](1,-1)[/tex] and [tex](3.5,1.5)[/tex]

4x + 1 -5x =2x +4(x-5)

Answers

Answer:

x = 3

Step-by-step explanation:

To answer for x first distribute the 4 in the parenthesis

4x + 1 - 5x = 2x +4x - 20

Next add or subtract the x's

-x + 1 = 6x - 20

Now subtract 6x and 1 on both sides to get x on the left and the rest on the right

-7x = -21

Lastly, divide -7 on both sides

x = 3

Exact Form:
x
=
20
7
x
=
20
7
Decimal Form:
x
=
2.
¯¯¯¯¯¯¯¯¯¯¯¯
857142
x
=
Mixed Number Form:
x
=
2
6
7
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