A research group is comparing the learning outcomes of students who are taught a lesson using four different teaching techniques. There are 75 students in the school who can participate in the experiment. Using a table of random digits, the researchers will randomly place the students into five equally sized treatment groups suitable for comparison, four of which will receive a different teaching technique and one of which will remain a control group.

Which design is the most appropriate for this experiment?

A Randomly number each person with 1, 2, 3, 4, or 5. Assign the students to the treatment groups based on their label.
B Select a student, and identify the first digit reading from left to right on a random number table. If the first digit is 1 or 2, assign that student to the technique 1 group. Similarly, digits 3 or 4, 5 or 6, 7or 8, and 9 or 0 go with the technique 2, technique 3, technique 4, and control groups, respectively. Repeat this process for each student.
C Number each student from 1 to 75. Reading the numbers from left to right on a random number table, identify 60 unique numbers from 1 to 75. Assign the students whose labels are the first 15 numbers to the technique 1 group. Assign the students whose labels are the second 15 numbers to the technique 2 group. Repeat this process two more times to assign the technique 3 and technique 4 groups. Finally, assign the remaining students to the control group.
D Number each student from 00 to 74. Reading the numbers from left to right on a table of random numbers and looking at two digits at a time, identify 60 unique two-digit numbers from 00 to 74. Assign the students whose labels are the first 15 numbers to the technique 1 group. Assign the students whose labels are the second 15 numbers to the technique 2 group. Repeat this process two more times to assign the technique 3 and technique 4 groups. Finally, assign the remaining students to the control group.

Answer:

(x + 1)² = 7

Step-by-step explanation:

Given:

-2x = x² - 6

We'll start by rearranging it to solve for zero:

x² + 2x - 6 = 0

The first term is already a perfect square so that's fine.  Normally, if that term had a non-square coefficient, you would need to multiply all terms a value that would change that constant to a perfect square.

Because it's already square (1), we can simply move to the next step, separating the -6 into a value that can be doubled to give us the 2, the coefficient of the second term.  That value will of course be 1, giving us:

x² + 2x + 1 - 1 - 6 = 0

Now can group our perfect square on the left and our constants on the right:

x² + 2x + 1 - 7= 0

x² + 2x + 1 = 7

(x + 1)² = 7

To check our answer, we can solve for x:

x + 1 = ± √7

x = -1 ± √7

x ≈ 1.65, -3.65

Let's try one of those in the original equation:

-2x = x² - 6

-2(1.65) = 1.65² - 6

- 3.3 = 2.72 - 6

-3.3 = -3.28

Good.  Given our rounding that difference of 2/100 is acceptable, so the answer is correct.

Answer:

ab=195

Step-by-step explanation:

Answer:

your answer will be option D. exponential decay

Step-by-step explanation:

have a nice day/ night bye ^_^

Answer:

B' = (-7,3)

Step-by-step explanation:

B = (7,3)

mirrored would be:

B' x position would be -7

B' y position would not change

B' = (-7,3)

Answer:

V=π(d

2)2h=π·(12.8

2)2·7.1≈913.62541ft³ Step-by-step explanation: because i said so

Answer:

Step-by-step explanation:

Supplementary angles have a sum of 180 degrees.

a+a-27.2=180

2a-27.2=180

2a=207.2

a=103.6, and since b=a-27.2

b=76.4

So one angle is 103.6 degrees and the other is 76.4 degrees.

Answer:

A congruence statement says that two polygons are congruent.

Step-by-step explanation:

To write a congruence statement, list the corresponding vertices in the same order.

Answer:

The answer is i (i^9)

Step-by-step explanation:

Answer:

D. (2,2)

Step-by-step explanation:

I did the test and I got it correct. :DD

Answer:

The area of the base is 80 in².  80 square inches.

Step-by-step explanation: V = b×h

Divide the volume by the height to find the area of the base.

400 ÷ 5 = 80

Answer:

the answer is A

Step-by-step explanation:

Answer:

The answer would be -4.

Step-by-step explanation:

yeah I didn't do too good on that unit with the integers kind of thing so, yeah....

how I did this question: imagine if you owe someone $9 but you only have $5 so you give them those $5 so now you only owe them for dollars.

Answer:

A. 14 cm

B. W== 0.5in

Step-by-step explanation:

Hope this helps

Answer: B

Step-by-step explanation:

196π=πr^2

196=r^2

14=r

14<30

Answer:

R= 16

M=  -12

N=  -4

Step-by-step explanation:

what you need to do next time is when you figer out one of the numbers see what it is multiplying by so you know what the numbers would be

Have a nice week.  Please mark as brainllest

[o]-[o]

\___/

Answer:

Your Answer Is 10

Step-by-step explanation:

1st Factor the Numerator and Denominator then cancel the common factor.

Hope It Help You If Yes then Please make me the Brainiest.

Thank You

Parshv

Answer:

2x⁴ - x² - 15

Step-by-step explanation:

(X² - 3)(2x² + 5)

[x²(2x² + 5)] - [3(2x² + 5)]

= 2x⁴ - x² - 15

Answer:

Area= 56 cm²

Step-by-step explanation:

Figure given is a rhombus

Area= 1/2*d1*d2

Answer:

3x - 2

Step-by-step explanation:

[tex]4x + 2 - \frac{ {x}^{2} + x - 12}{x - 3} \\ \\ = 4x + 2 - \frac{ {x}^{2} + 4x - 3x- 12}{x - 3} \\ \\ = 4x + 2 - \frac{ {x}(x + 4) - 3(x + 4)}{x - 3} \\ \\ = 4x + 2 - \frac{ (x + 4) \cancel{(x- 3)}}{\cancel{(x- 3)}} \\ \\ = 4x + 2 - (x + 4) \\ \\ = 4x + 2 - x - 4 \\ \\ = 4x - x + 2 - 4 \\ \\ = 3x - 2[/tex]

Answer:

the third one has a 2 acute angles 2 abuse angles and the x value is 110

Step-by-step explanation

the x value has to be bigger then 90 degree angles because it is a abuts angle and the 57 angle is a acute angle

Answer:

nah and yall kids stop looking on here to cheat ronnie wilson

Step-by-step explanation:

Answer:

Nobody can answer this question if you don't tell us what are the ratios that are 'below'. We have no answers to choose from...

Answer:

33/100

Step-by-step explanation:

33/100 bc percentage goes up to 100

Answer:

Step-by-step explanation:

Rationalize the denominator of b. So, multiply the numerator and denominator by [tex]\sqrt{x}[/tex]

[tex]b = \frac{(1-2\sqrt{x}) *\sqrt{x}}{\sqrt{x}*\sqrt{x} }=\frac{1*\sqrt{x} -2\sqrt{x} *\sqrt{x} }{\sqrt{x} *\sqrt{x} }\\\\=\frac{\sqrt{x} -2x}{x}\\[/tex]

Now, find a +b

[tex]a +b = \frac{2x+\sqrt{x} }{x}+\frac{\sqrt{x} -2x}{x}\\\\=\frac{2x+\sqrt{x} +\sqrt{x} -2x}{x}[/tex]

Combine like terms

[tex]= \frac{2x-2x+\sqrt{x} +\sqrt{x} }{x}\\\\=\frac{2\sqrt{x} }{x}[/tex]

Now find (a + b)²

(a +b)² = [tex](\frac{2\sqrt{x} }{x})^{2}[/tex]

          [tex]= \frac{2^{2}*(\sqrt{x} )^{2}}{x^{2}}\\\\= \frac{4* x}{x^{2}}\\\\= \frac{4}{x}[/tex]

Hint: [tex]\sqrt{x} *\sqrt{x} =\sqrt{x*x}=x[/tex]

Answer:

Positive

Step-by-step explanation:

Two positive integers multiplied will always be positive.

Answer:

Positive

Step-by-step explanation:

two positive will always be a positive because of the rule of multiplication

Answer:

Given that the equation of the revenue is R=2x2+55x+10 and the equation of the cost is C=2x2 – 15x – 40, you will get the profit by subtracting the revenue from the cost: R-C=P. Therefore, P=(2x2+55x+10)-(2x2 – 15x – 40). You will get P=70x+50 where x is is the number of cellphones sold. If 240 cellphones are sold, then the profit is 16850 dollars.

Step-by-step explanation:

The profit expression is 70x + 50 and the profit if 240 cell phones are sold is $16,850

where,

x = number of cell phones sold.

Profit = Revenue - cost

= (2x² + 55x + 10) - (2x² – 15x – 40)

= 2x² + 55x + 10 - 2x² + 15x + 40

Profit = 70x + 50

Profit = 70x + 50

= 70(240) + 50

= 16,800 + 50

= $16,850

Learn more about profit:

https://brainly.com/question/23103804

Answer:

$640 is how much she will make in in regular hours.

Step-by-step explanation:

Create an equation from the word problem and solve.

Option A is correct, $640 is the pay for her regular hours.

Two or more expressions with an Equal sign is called as Equation.

Given that Tania earns $16 per hour at the Glendale Florist.

She regularly works 40 hours per week.

She is paid time-and-a-half for each hour of overtime work

Last week she worked 43 hours.

We need to find the payment she received for her regular hours.

16h is the expression to find the pay for h hours.

As she work for 40 hours.

Now plug in h as 40.

16×40

$640

Hence, option A is correct, $640 is the pay for her regular hours.

To learn more on Equation:

https://brainly.com/question/10413253

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Step-by-step explanation:

<c =90 °

So, Pythagoras theorem can be used,

Hypotenuse ² = base ² + altitude ²

AB²=AC²+BC²

11²=AC²+4²

11²-4²=AC²

121-16=AC²

Root 105=AC

AC=10.2 cm

The length of AC is 10.25 cm

If ΔABC is a right angle triangle, then

AB² = BC²+AC²

where AB = Hypotenuse, BC & AC are adjacent sides of the right angle

Given, hypotenuse = AB = 11 cm

One of adjacent sides = BC = 4 cm

We have to find the length of AC.

Using pythagorean theorem,

AB² = BC²+AC²

⇒ AC² = AB² - BC²

⇒ AC² = 11²-4²

⇒ AC² = 121-16

⇒ AC = √105

⇒ AC = 10.25

So the length of AC = 10.25 cm

Learn more about pythagorean theorem here :

https://brainly.com/question/343682

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Answer:

4.82 × 10^4

Step-by-step explanation: