Twenty students randomly assigned to an experimental group receive an instructional program; 30 in a control group do not. After 6 months, both groups are tested on their knowledge. The experimental group has a mean of 38 on the test (with an estimated population standard deviation of 3); the control group has a mean of 35 (with an estimated population standard deviation of 5). Using the .05 level, evaluate the researcher's hypothesis that the instructional program affects students' knowledge. What is the correct cutoff score(s)

Answer:

The critical value is [tex]T_c = 1.7056[/tex]

The 90% confidence interval for the mean repair cost for the refrigerators is ($52.875, $68.165).

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 27 - 1 = 26

90% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 26 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.9}{2} = 0.95[/tex]. So we have T = 1.7056, which means that the critical value is [tex]T_c = 1.7056[/tex]

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 1.7056\frac{23.29}{\sqrt{27}} = 7.645[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 60.52 - 7.645 = $52.875.

The upper end of the interval is the sample mean added to M. So it is 60.52 + 7.645 = $68.165.

The 90% confidence interval for the mean repair cost for the refrigerators is ($52.875, $68.165).

Answer:

The correct graph of h(x) will be number 3 (c).

Step-by-step explanation:

We have the function h(x) = |x| + 0.5

On putting x=0, in the function h(x), we get,  

h(0) = |0| + 0.5

h(0)=0 + 0.5

h(0)=0.5

Thus, the point (0,0.5) lie on the graph of h(x).

The graph that represents the function h(x) is graph (c)

The equation is given as:

h(x) = |x| + 0.5

The above equation is an absolute value function

An absolute value function is represented as:

h(x) = a|x + h| + k

Where:

Vertex = (h,k)

By comparing h(x) = a|x + h| + k and h(x) = |x| + 0.5, we have:

h = 0 and k = 0.5

So, the vertex is (0,0.5)

The graph that has a vertex of (0,0.5) is graph (c)

Hence, the graph that represents the function h(x) is graph (c)

Read more about absolute value function at:

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Answer:

2k-3

Step-by-step explanation:

the square of k is k times k so 2k (two times k) and less than three means minus three.

Answer:

50

Step-by-step explanation:

Sum Even numbers

n = 50

d = 2

a1 = 2

The last number is

an = a1 + (n-1)d

an = 2 + (50 - 1)*2

an = 2 + 49 * 2

an = 2 + 98

an = 100

Sum of the even numbers

Sum = (a1 + a50)*n/ 2

Sum = (2 + 100)*50/2

sum = 102 * 25

sum = 2550

Sum of the first 50 odd numbers

a1 = 1

n = 50

d = 2

l = ?

Find l

l = a1 + (n - 1)*2

l = 1 + 49*2

l = 99

Sum

Sum = (1 + 99)*50/2

Sum = 2500

The difference and answer is 2550 - 2500  = 50

Answer: Option 1

Degrees of 6 or greater

Answered by Gauthmath must click thanks and mark brainliest

Answer:

43

Step-by-step explanation:

only 7 out of the 50 got both wrong

Answer:

Step-by-step explanation:

Write the options so they are homogeneous in content. • Use answers given in previous open-ended exams to provide realistic distractors. 2. Use a Question ...

Answer:

320/3

Step-by-step explanation:

First find the common ratio

20/80 = 1/4

The sum of an infinite geometric series

sum = a1/ (1-r)  where a1 is the first term and r is the common ratio

         =80/ ( 1-1/4)

         = 80/(3/4)

        = 80 *4/3

      = 320/3

Respuesta:

3650

Explicación paso a paso:

Dado que :

Principal, P = capital prestado

Tasa anual, r = 10% * 6 = 60%

Interés = 1140

Periodo = 6 meses y 10 días = (6 * 30) +10 = 190 días

Conversión a años:

Periodo = 190/365

Usando la relación:

Interés = principal * tasa * tiempo

1140 = P * 60% * (190/365)

1140 = 0.3123287P

P = 1140 / 0,3123287

P = 3650

Answer:

$4,966.25

Step-by-step explanation:

3 x 15 = 45

After 15 years, Naomi would have earned a total of 45% interest rate.

3,425 x 1.45 = 4,966.25

Don't use .45 as the multiplier

3,425 x .45 = 1,541.25 <- incorrect

Answer:

6(5+k)

Step-by-step explanation:

The sum of 5  and k

5+k

6 times the sum

6(5+k)

Answer:

hxvkgyjdh ht yshysfhyys is not working properly configured form and the kids will not work with a little over again. thank you

Answer:

2 Inches

Step-by-step explanation:

Area of a triangle = (1/2)* Base * Hight

lets consider the base of the triangle is X inches,

then, Hight of the triangle is 2X

Then the Area of the Angle is = (1/2)*X*2X

                                               4 = x^{2}

                                               X = 2

Answer:

6.5sin(.04x+.4pi)-8

The function intersects its midline at (-pi,-8) and has a maximum point at (pi/4, "-1.5). The  final equation is h(x) = 4 sin(2x +  π /2) + 3.

A function is defined as a relation between the set of inputs having exactly one output each.

The function intersects its midline at (3π/4, 3) then the midline is d= 3.

The amplitude is just the positive distance between the maximum/minimum and the midline,

so the amplitude a = 7 - 3 = 4

Also, given that period is 2π/b and the fact that the period is π from our given maximum,

we have the equation 2π/b= π where b = 2

we know that the phase shift, -c/b is - π/4 (or  to the left)

since -π /4. Therefore, c = π /2.

our final equation is

h(x) = 4 sin(2x +  π /2) + 3.

Learn more about function;

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Answer:

The answer is "0.7616".

Step-by-step explanation:

Using formula:

[tex]\text{P( at least one de-fective) = 1 - P( all calculators work )}[/tex]

                                          [tex]= 1-(\frac{34}{48}\times \frac{33}{47}\times \frac{32}{46}\times \frac{31}{45})\\\\= 1-(\frac{34}{1}\times \frac{11}{47}\times \frac{1}{23}\times \frac{31}{45})\\\\=1-(\frac{11594}{48647})\\\\=\frac{48647-11594}{48647}\\\\=\frac{37051}{48647}\approx 0.7616[/tex]

9514 1404 393

Answer:

  x, y ∈ all real numbers

Step-by-step explanation:

For your function ...

  f(x, y) = 2x^3·y -xy

there appear to be no values of x or y for which the function is undefined. The domain for both x and y is "all real numbers."

Answer:

Step-by-step explanation:

x^2 - 9x + 3 = 0 is a quadratic whose coefficients are a = 1, b = -9 and c = 3.

Use the quadratic formula to solve it.

The discriminant, b^2 - 4ac, is 81 - 4(1)(3), or 81 - 12, or 69.

The roots are:

      -b ± √(discriminant)

x = -------------------------------

              2a

And these roots in this particular problem are:

      -(-9) ± √69                    9 ± √69

= ------------------------------- = ----------------

              2(1)                                2

Answer:

-2 <× <35

i hop i helped you sold the question

Answer:

[tex]P_{95\%}=(0.333,0.527)[/tex]

Step-by-step explanation:

From the question we are told that:

Sample size [tex]n=100[/tex]

Selected sample [tex]x=43[/tex]

Confidence Interval [tex]CI=95\%[/tex]

Significance Level [tex]\alpha=0.05[/tex]

Probability of picking nose is

[tex]P=\frac{x}{n}[/tex]

[tex]P=\frac{43}{100}[/tex]

[tex]P=0.43[/tex]

Generally the equation for standard error is mathematically given by

[tex]S.E=\sqrt{p*(1-p)}{n}[/tex]

[tex]S.E=\sqrt{0.4*(1-0.57)}{100}[/tex]

[tex]S.E=0.0495[/tex]

Therefore

The proportions 95\% interval is

[tex]P_{95\%}=[P-1.96x SE(P),P+1.96*SE(P)][/tex]

[tex]P_{95\%}=(0.43-1.96*0.0495,0.43+1.96*0.045)[/tex]

[tex]P_{95\%}=(0.333,0.527)[/tex]

Answer:

12.6 mi

Step-by-step explanation:

Arc length = 2πr (Θ/360)

2π(12) (60/360)

= 12.6 mi

Answered by g a u t h m a t h

Answer:

Since I cant say which answer due to no graph, I'll tell you How to do so.

Step-by-step explanation:

if it is A, then the there is at least one angle or line length that is not the same. To find the area of a grided shape, use the traingle theorm of a^2+b^2=c^2.

if it is B, that meants moving the shape to the other will result in a perfect fit. Be sure to find if all side lengths are the same as that means that the shape IS congrouent, as equal side length means equal angles. However, it will not be this choice if the shape is mirrored to the other

A rotation and tranlastion means it is flipped either upside down or up and moved to the shape.

D, a reflection, which means its the opposite. Like a mirrored shape. Then you move it.

Answer:

The answer is "[tex]\chi^2_{L} = 4.575 \ and\ \chi^2_{U}= 19.675[/tex]"

Step-by-step explanation:

[tex]n=12\\\\\ c= 0.9[/tex]

Calculating the level of significance [tex](\alpha) = 1 -c[/tex]

                                                                  [tex]=1-0.9\\\\=0.1[/tex]

Calculating the degrees of freedom:

[tex]df=n-1=12-1=11[/tex]

Calculating the critical value:

Applying the Chi-Square table, the critical values for the two-tailed test with a degree of freedom  (11) for the significance level of [tex]\alpha = 0.1[/tex]:

[tex]\chi^2_{L} = 4.575 \\\\\chi^2_{U}= 19.675[/tex]

please mark this answer as brainlist

Answer:

Placements are basically extended internships or work experience assignments

Step-by-step explanation:

9514 1404 393

Answer:

  B

Step-by-step explanation:

To find the inverse of y = f(x), solve the equation x = f(y) for y. For these functions, that's about the easiest way to do it.

  A. x = ∛(3y)   ⇒   x³ = 3y   ⇒   x³/3 = y . . . . . does not match g(x)

  B. x = 11y -4   ⇒   x +4 = 11y   ⇒   (x +4)/11 = y . . . . matches g(x)

  C. x = 3/y -10   ⇒   x +10 = 3/y   ⇒   3/(x+10) = y . . . . does not match g(x)

  D. x = y/12 +15   ⇒   x -15 = y/12   ⇒   12(x -15) = y . . . . does not match g(x)

_____

Additional comment

This is repeated application of the "solve for ..." process. In general, that process "undoes" what is "done" to the variable. The order of operations can tell you the order of the things that are done. The undoing is in the reverse order.

You need to be completely comfortable with the properties of equality (addition, subtraction, multiplication, division), and you need to understand the inverse functions of the functions we usually use: (powers, roots), (exponentials, logarithms), (trig functions, inverse trig functions). Of course, the inverse of addition is subtraction; the inverse of multiplication is division.

__

Above, we used a "shortcut" a couple of times:

  a = b/c   ⇒   c = b/a . . . . . equivalent to multiplying both sides by c/a.

Answer:

1250 supermarkets

Step-by-step explanation:

Given

[tex]\frac{dN}{dt} = N(1 - 0.0008N)[/tex]

[tex]N(0) = 1[/tex]

Required

Number of supermarkets over a long period of time

To do this, we simply set

[tex]\frac{dN}{dt} = 0[/tex]

So, we have:

[tex]N(1 - 0.0008N) = 0[/tex]

Split

[tex]N = 0\ or\ 1 - 0.0008N = 0[/tex]

Solve: [tex]1 - 0.0008N = 0[/tex]

Collect like terms

[tex]0.0008N = 1[/tex]

Make N the subject

[tex]N = \frac{1}{0.0008}[/tex]

[tex]N = 1250[/tex]

So:

[tex]\lim_{t \to \infty} N(t) = 1250[/tex]

Answer:

y=-1/5x-11/5

Step-by-step explanation:

perpendicular, product of both gradients = -1

hence, slope = -1/5

y=-1/5x+c

sub y=-1, x=-6

-1=-1/5(-6)+c

c = -1-6/5=-11/5

y=-1/5x-11/5

Answer:

1 and 5 sevenths of a bag

Step-by-step explanation:

2/7 males half to it takes 4/7 to make a full one multiply 4 by 3 and you get 12/7 so that makes 1 and 5/7

Answer:

don't know...........

Answer:

a. 168000 for Eyeconnect, 132000 for Topconnect

b. 100,000

Step-by-step explanation:

a.

Because the change in customers are only due to leaving companies, we can say that, after one year, Eyeconnect loses 10% of its customers to Topconnect and Topconnect loses 5% of its customers to Eyeconnect. This represents all changes in customers.

First, we can calculate how much Eyeconnect loses, which is 10% of 180,000 = 0.1 * 180,000 = 18,000 . They then have 180,000 - 18,000 = 162,000 employees

Next, Topconnect loses 120,000 * 5% = 120,000 * 0.05 = 6,000. They then have 120,000-6,000 = 114,000 employees

We can then add the customer amounts. Note that we are subtracting both sides before adding as both companies gain and lose customers simultaneously.

We can then add how much one company lost to the other company's customers.

Eyeconnect gains 6,000 customers, so they then have 162,000 + 6,000 = 168000 employees. Topconnect gains 18,000 customers so they then have 114,000 + 18,000 = 132,000 employees

b.

After many years, the number of customers Eyeconnect has will be less than the number of customers that Topconnect has. One way to find the end amount of customers that Eyeconnect has is to figure out when the customer bases even out, or when Eyeconnect loses the same amount of customers as Topconnect so the customer base stays the exact same. We know that no customers leave or join the companies except to leave/join the other, so the total amount of customers between the two companies stays the exact same. The amount of customers is 180,000 + 120,000 = 300,000. Therefore, at the end amount,

Eyeconnect customers (E) + Topconnect customers (T) =300,000

Furthermore, if the amount of customers that leave Eyeconnect is the same that leaves Topconnect, we can say

E * 0.1 = T * 0.05

divide both sides by 0.05 to isolate the T

E * 0.1 / 0.05 = T

2 * E = T

plug that into the first equation

E + 2 * E = 300,000

3 * E = 300,000

divide both sides by 3 to isolate E

E = 100,000 after many years

Answer:

1¼ cups

Step-by-step explanation:

2¼ ÷ 1/4/5 =

9/4 ÷ 9/5 =

9/4 x 5/9 =

5/4 = 1¼