Suppose that the length of a confidence interval is 0.06 when the sample size is 400. Determine how the sample size must change to decrease the length of the confidence interval to 0.03 (Use decimal notation. Give your answer as a whole number:) new sample size:

Original price: $46.44

Price after variation: $43

Variation= 46.44-43 = $3.44

46.44 x = 3.44

Solve for x:

x= 3.44/46.44

x= 0.07407

Multiply by 100:

0.074 x 100 = 7.4%

so correlation coefficient = σ^XY/σ^Xσ^Y = 1.225 / 1.36 = 0.9

Step-by-step explanation:                                                                          

a) We need to find the conditional p m f of X when Y = 1.

So, when Y = 1, there are only two X values: X =1 and X =2.

X can have any of the following values: 0, 1, 2, or 3                                                                                                        

so P(0) = 0/ 0.2 = 0          

P(1) = 0.1/(0.1+0.1) = 0.5

P(2) = 0.1/( 0.1+ 0.1) = 0.5

P(3) = 0/ 0.2 = 0

b)  The correlation coefficient of X and Y isρXY              

ρ^XY=(X,Y)=(X,Y)/σ^Xσ^Y=σ^XY/σ^Xσ^Y

We will calculate σ^X first by μ^x

f x(x) = 0.2; x = 0

= 0.2; x =1

= 0.2 ; x = 2

= 0.4 ; x = 3

μ^x = 0.2 * 0 + 0.2 * 1 + 0.2 * 2 + 0.4 * 3 = 1.8

σ^X^ 2 = 0.2 * 1.82 + 0.2 * 0.82 + 0.2 * 0.22 + 0.4 * 1.22 = 1.36

σ^X = 1.166

We will calculate σ^y first by μ^y

f^ x (X) = 0.2; y = 0

= 0.2; y =1

= 0.2 ; y= 2

= 0.4 ; y = 3

μ^y = 0.2 * 0 + 0.2 * 1 + 0.2 * 2 + 0.4 * 3 = 1.8

σ^y^ 2 = 0.2 * 1.82 + 0.2 * 0.82 + 0.2 * 0.22 + 0.4 * 1.22 = 1.36

σ^y = 1.166

Now we will calculate σ^XY

σ^2^XY = 0.4 * ( 3 - 1.8)* ( 3-1.8) + 0.2 *( 0 -1.8) * ( 0 - 1.8) + 0.1 * ( 1- 1.8) * ( 1- 1.8) + 0.1 * ( 2 -1.8) * ( 1 -1.8) + 0.1 * ( 1 - 1.8) * ( 2 - 1.8) + 0.1 * ( 2 - 1.8) * ( 2 - 1.8) = 1.26

σ^XY = 1.225        

so correlation coefficient = σ^XY/σ^Xσ^Y = 1.225 / 1.36 = 0.9

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To factor the expression 4x^2 - 25, we can use the difference of squares formula, which states that a^2 - b^2 can be factored as (a + b)(a - b).

In this case, we have 4x^2 - 25, which can be written as (2x)^2 - 5^2. Comparing it with the difference of squares formula, we can identify that a = 2x and b = 5. Therefore, the correct option is:

b. (2x)^2 - (5)^2

Using the difference of squares formula, we can factor it as follows:

(2x + 5)(2x - 5)

Hence, the correct factorization of 4x^2 - 25 is (2x + 5)(2x - 5), which is equivalent to option b.

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Answer:C

Step-by-step explanation:

Answer:

Step-by-step explanation:

B is the answer

Answer:

39 °

Step-by-step explanation:

Isosceles means two angles , x, are =

x + x + 102   = 180     ( the sum of triangle angles always = 180)

2x = 78

x = 39 °

Answer:

5) x = 4, -2

6) x = sqroot 22 - 6

7) x = -5/2 +- i sqrt 23/2

8) x = 4, -1

Answer:

5. x=4 x=-2

6. x=±\(\sqrt{22\) -6

7. x= \(-\frac{5}{2}\)±\(\frac{\sqrt{i23}}{2}\)

8. x=4 x=-1

Step-by-step explanation:

I used math

way

The 95% confidence interval for the average maximum heart rate is given as follows:

(158.6, 180.8).

The t-distribution is used when the standard deviation for the population is not known, and the bounds of the confidence interval are given according to the following rule:

\(\overline{x} \pm t\frac{s}{\sqrt{n}}\)

In which the variables of the equation are presented as follows:

The critical value, using a t-distribution calculator, for a two-tailed 95% confidence interval, with 9 - 1 = 8 df, is t = 2.306.

Using a calculator, the remaining parameters are given as follows:

\(\overline{x} = 169.7, s = 14.4, n = 9\)

Hence the lower bound of the interval is given as follows:

169.7 - 2.306 x 14.4/sqrt(9) = 158.6.

The upper bound of the interval is given as follows:

169.7 + 2.306 x 14.4/sqrt(9) = 180.8.

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Answer:

\( \frac{5}{6} * 20 = \frac{5 * 20}{6} = \frac{100}{6} = \frac{50}{3} = 16\frac{2}{3} \)

Step-by-step explanation:

\( \frac{5}{6} * 20 \)

Multiply

\( = \frac{5 * 20}{6} \)

\( = \frac{100}{6} \)

Simplicity by reducing the fraction. Divide the numerator and denominator by 2, respectively.

\( = \frac{50}{3} \)

Divide 50 by 3 to get a mixed number

\( = 16\frac{2}{3} \)

Answer:

a) E

b) line segment AB

Step-by-step explanation:

a) E

b) line segment AB (It's AB with the line over it - no arrowheads)

Answer:

a)e

b)a

c)e

Step-by-step explanation:

Answer:

f(3) = 3 + 1 = 4

Step-by-step explanation:

Since 3 > 0, we need to focus on the part of the function where x > 0. So:

f(3) = 3 + 1 = 4.

Answer:

B

Step-by-step explanation:

Tuesday: 16.0

Wednesday: 16.1

Thursday: 16.0

Friday: 15.1

Tuesday's and Thursday's rounded number of pounds of paper recycled is 16.

Answer:

c

Step-by-step explanation

7x3=21

125-34=91

91+21=112

We can reject the null hypothesis and conclude that there is evidence to support the alternative hypothesis that the left foot is longer than the right foot.

A statistical test is required to determine whether the length of the left foot is greater than the length of the right foot. The null hypothesis states that there is no difference in average length between the left and right feet. The alternative hypothesis is that the left foot's average length is greater than the right foot's average length.

This hypothesis is one-tailed, as we are only interested in whether the left foot is longer than the right foot. We are not considering the possibility that the right foot could be longer than the left foot.

A t-test can be used to determine whether the difference in average length between the left and right feet is statistically significant. We can reject the null hypothesis and conclude that there is evidence to support the alternative hypothesis that the left foot is longer than the right foot if the p-value of the t-test is less than the chosen significance level (e.g., 0.05).

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Answer:

-72x - 53y + 287 = 0.

Step-by-step explanation:

To find the equation of the image of the circle, we need to reflect each point on the circle in the given line mirror.

The line mirror equation is given as 4x + 7y + 13 = 0.

The reflection of a point (x, y) in the line mirror can be found using the formula:

x' = (x - 2Ay - 2B(Ax + By + C)) / (A^2 + B^2)

y' = (y - 2Bx + 2A(Ax + By + C)) / (A^2 + B^2)

where A, B, and C are the coefficients of the line mirror equation.

For the given line mirror equation 4x + 7y + 13 = 0, we have A = 4, B = 7, and C = 13.

Now, let's find the equations of the image of the circle.

The original circle equation is x² + y² + 16x - 24y + 183 = 0.

Using the reflection formulas, we substitute the values of x and y in the circle equation to find x' and y':

x' = (x - 2Ay - 2B(Ax + By + C)) / (A^2 + B^2)

= (x - 2(4)y - 2(7)(4x + 7y + 13)) / (4^2 + 7^2)

= (x - 8y - 8(4x + 7y + 13)) / 65

= (x - 8y - 32x - 56y - 104) / 65

= (-31x - 64y - 104) / 65

y' = (y - 2Bx + 2A(Ax + By + C)) / (A^2 + B^2)

= (y - 2(7)x + 2(4)(Ax + By + C)) / (4^2 + 7^2)

= (y - 14x + 8(Ax + By + C)) / 65

= (y - 14x + 8(4x + 7y + 13)) / 65

= (57x + 35y + 104) / 65

Therefore, the equation of the image of the circle is:

(-31x - 64y - 104) / 65 + (-57x + 35y + 104) / 65 + 16x - 24y + 183 = 0

Simplifying the equation, we get:

-31x - 64y - 57x + 35y + 16x - 24y + 183 + 104 = 0

-72x - 53y + 287 = 0

So, the equation of the image of the circle is -72x - 53y + 287 = 0.

Answer:

\( x = - 1\)

\(x + 1 = 0\)

\( {(x + 1)}^{2} = {x}^{2} + 2x + 1 = 0\)

So m = 2 and n = 1, meaning m + n = 3.

The surface area of the sphere is 1810 cm²

A sphere is a three-dimensional object that is round in shape. Examples of object with spherical shape is a ball, an egg e.t.c.

The area occupied by a three-dimensional object by its outer surface is called the surface area.

The surface area of sphere is expressed as;

A = 4πr². where r is the radius.

A = 4 × 3.14 × 12²

A = 1809.7 cm²

approximately to the nearest whole number

A = 1810 cm²

Therefore the surface area of the sphere to the nearest whole number is 1810 cm².

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Answer:

Is the line going through negative dot or positive? Think about it.

Step-by-step explanation:

Anyway my teacher came into me anyway its a positive answer. so A or B

Answer:

  2.5%

Step-by-step explanation:

You want the percentage below 335 if the distribution is normal with a mean of 555 and a standard deviation of 110, using the empirical rule.

The z-score of 335 is ...

  Z = (X -µ)/σ

  Z = (335 -555)/110 = -220/110 = -2

The empirical rule tells you that 95% of the distribution is between Z = -2 and Z = 2. That is, 5% of the distribution is evenly split between the tails Z < -2 and Z > 2. Half that value is in each tail.

  P(X < 335) = 5%/2 = 2.5%

The percentage of people taking the test who score below 335 is 2.5%.

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Answer:

Step-by-step explanation:

Answer:

Uggghhh

Step-by-step explanation:

I dont know

Answer:

Part A: Garcia mixed 4 cups of red with 1 cup of yellow.

Part B: 1/4 because 4 cups of red requires 1 cup of yellow, so 1 divided by 4 is 1/4.

Part C: $7

Hope this helps! :)

Step-by-step explanation:

Complete

Find the integral of  \(f(x) =  16sin^2 (x ) cos(x) dx\)

Answer:

The solution is    \(\frac{16}{3} sin^{3}x + c\)

Step-by-step explanation:

So

   \(Let \  u  =  sin(x)\)

=>  \(\frac{du}{dx}  =  cos (x)\)

=>   \(du  =  cos(x)dx\)

So

   \(\int\limits {16sin^2 (x ) cos(x) dx} \, \equiv \int\limits {16u^2  du}\)

=>  \(\int\limits {16u^2  du} = 16 [\frac{u^3}{3} ] + c\)

Now substituting sin(x) for u  

      \(\frac{16}{3} u^3 + c  =  \frac{16}{3} sin^{3}x + c\)

So the  integral of  \(f(x) =  16sin^2 (x ) cos(x) dx\)  is

      \(\frac{16}{3} sin^{3}x + c\)

Step-by-step explanation:

The way you can think about volume is that we have some cross sectional area times the height of the solid.

27.

The volume of a square based pyramid is

\(v = {s}^{2} ( \frac{h}{3} )\)

where h is the height of the pyramid

s is the side length of the square base.

S=7

h=12

\(v = {7}^{2} ( \frac{12}{3} ) = 49 \times 4 = 196\)

28. The volume of a rectangular prism

\(v = l \times w \times h\)

where l is length

w is width

h is height

\(v = 11 \times 11 \times 8 = 968\)

29.

Use the same formula in 27

\(v = 100(3) = 300\)

30.

Volume of a Cylinder is

\(v = \pi {r}^{2} h\)

where r is the radius of the circle

where h is the height

r is half of the diameter

The diameter is 22, thus the radius is 11.

\(v = {11}^{2} (8)(\pi)\)

\(v = 968\pi\)

pi is approximately 3.14

\(v = 3041.06\)

31. Volume of A Sphere

\( \frac{4}{3} \pi {r}^{3} = v\)

The radius is half of diamter, thus r=7

\( \frac{4}{3} \pi( {7}^{3} ) = 1436.76\)

Answer:

{7, 9}

(Numbers from 1 to 10 equal to or greater than 7 are 7 and 9)

Step-by-step explanation:

We have to find the set of whole number greater than and equal to 7 from 1 to 10,

Now, From 1 to 10, the odd numbers are, 1,3,5,7,9,

And of these, 7 and 9 are equal to or greater than 7

So, we get the set,

{7, 9}

Answer:

82

Step-by-step explanation:

Plug in the variables into the equation and solve for B but remember your order of operations when solving multiplication/division before addition/subtraction.

B = 4*25-9*2

B = 100-18

B = 82

Answer:

-48

Step-by-step explanation:

we can see each number is getting doubled but flipped from negative and positive and vise versa. aka getting multiple by negative 2

we can also double check our work by multiplying each number in the sequence we have by -2 and make sure it follows the sequence.

The values of x for which f(x) = 7 are x = 61 and x = 21.

To find the values of x for which f(x) = 7, we can set up the equation and solve for x.

The given function is f(x) = 0.5|x - 41| - 3.

Setting f(x) equal to 7, we have:

0.5|x - 41| - 3 = 7.

First, let's isolate the absolute value term:

0.5|x - 41| = 7 + 3.

0.5|x - 41| = 10.

To remove the absolute value, we can consider two cases:

Case: (x - 41) is positive or zero:

0.5(x - 41) = 10.

Multiplying both sides by 2 to get rid of the fraction:

x - 41 = 20.

Adding 41 to both sides:

x = 61.

So x = 61 is a solution for this case.

Case: (x - 41) is negative:

0.5(-x + 41) = 10.

Multiplying both sides by 2:

-x + 41 = 20.

Subtracting 41 from both sides:

-x = -21.

Multiplying both sides by -1 to solve for x:

x = 21.

So x = 21 is a solution for this case.

Therefore, the values of x for which f(x) = 7 are x = 61 and x = 21.

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Answer:

Step-by-step explanation:

3y + 39 = 33

3y = -6

y = -2

1/4(-2)= -2/4 = -1/2

The volume of the rectangular prism is given as follows:

344 cubic yards.

The volume of a rectangular prism, with dimensions length, width and height, is given by the multiplication of these dimensions, as follows:

Volume = length x width x height.

Each ft is composed by 1/3 yards, hence the dimensions in yards are given as follows:

Hence the volume of the prism, in cubic yards, is given as follows:

V = 8.33 x 10.33 x 4

V = 344 cubic yards.

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