I need help pls. Algebra

Answer:

a)

H₀ : µd = 0  

H₁ : µd < 0  

b)

The test statistic is

tₙ₋₁ = α / s√n

c)

at 0.10 level of significance,

tₙ₋₁ , ₐ

t₃₀₋₁ , ₀.₁₀ = t₂₉, ₀.₁₀ = 1.311

d)

given that  T(critical) = 1.62

∴ T(critical) = 1.62 > t₂₉, ₀.₁₀ = 1.311

at 10% level of significance,

REJECT H₀

Since 1.62 > 1.311, we can reject the null hypothesis.

Answer:

5 5/12

Step-by-step explanation:

31/6 feet + 1/4 foot

= 31/6 + 1/4

= [(31 * 4) / 6 * 4] + [(1 * 6) / 4 * 6]

=  [ 124/24 ] + [ 6/24 ]

= (124 + 6) / 24

= 130 / 24

= 5 10/24

= 5 5/12

Hope this helps!  Tell me if I'm wrong!

[tex]5(2^x+4)=15\\2^x+4=3\\2^x=-1\\x\in\emptyset[/tex]

Answer:

no solutions

Step-by-step explanation:

5(2^x+4)=15

Divide each side by 5

5/5(2^x+4)=15/5

(2^x+4)=3

Subtract 4 from each side

2^x = 3-4

2^x = -1

This cannot happen so there are no solutions

Answer:

-23

Step-by-step explanation:

-8+(-15) means that you are subtracting 15 from -8. So you end up with -8-15=-23.

Answer:

56.8

Step-by-step explanation:

7.1*8=56.8

Answer:

The chi - square test can be [tex]\approx[/tex] 0.667

Step-by-step explanation:

From the given data :

The null hypothesis and the alternative hypothesis can be computed as:

Null hypothesis: The number of customers does  follow  a uniform distribution

Alternative hypothesis: The number of customers does not  follow  a uniform distribution

We learnt that: Carl recorded the number of customers who visited his new store during the week:

Day              Customers

Monday               17

Tuesday              13

Wednesday         14

Thursday              16

The above given data was the observed value.

However, the question progress by stating that : He expected to have 15 customers each day.

Now; we can have an expected value for each customer  as:

                      Observed Value                   Expected Value

Day                 Customers                        

Monday                17                                          15

Tuesday               13                                          15

Wednesday          14                                          15

Thursday               16                                         15

The Chi square corresponding to each data can be determined by using the formula:

[tex]Chi -square = \dfrac{(observed \ value - expected \ value )^2}{expected \ value}[/tex]

For Monday:

[tex]Chi -square = \dfrac{(17 - 15 )^2}{15}[/tex]

[tex]Chi -square = \dfrac{(2)^2}{15}[/tex]

[tex]Chi - square = \dfrac{4}{15}[/tex]

chi - square = 0.2666666667

For Tuesday :

[tex]Chi -square = \dfrac{(13- 15 )^2}{15}[/tex]

[tex]Chi -square = \dfrac{(-2)^2}{15}[/tex]

[tex]Chi - square = \dfrac{4}{15}[/tex]

chi - square = 0.2666666667

For Wednesday :

[tex]Chi -square = \dfrac{(14- 15 )^2}{15}[/tex]

[tex]Chi -square = \dfrac{(-1 )^2}{15}[/tex]

[tex]Chi -square = \dfrac{(1 )}{15}[/tex]

chi - square = 0.06666666667

For Thursday:

[tex]Chi -square = \dfrac{(16- 15 )^2}{15}[/tex]

[tex]Chi -square = \dfrac{(1 )^2}{15}[/tex]

[tex]Chi -square = \dfrac{(1 )}{15}[/tex]

chi - square = 0.06666666667

                   Observed Value   Expected Value    chi - square

Day                 Customers                        

Monday                17                     15                       0.2666666667

Tuesday               13                     15                       0.2666666667

Wednesday          14                     15                       0.06666666667

Thursday               16                    15                       0.06666666667

Total :                                                                        0.6666666668

The chi - square test can be [tex]\approx[/tex] 0.667

At level of significance ∝ = 0.10

degree of freedom = n - 1

degree of freedom = 4 - 1

degree of freedom = 3

At ∝ = 0.10 and df = 3

The p - value for the chi - square test statistics is 0.880937

Decision rule: If the p - value is greater than the level of significance , we fail to reject the null hypothesis

Conclusion: Since the p - value is greater than the level of significance , we fail to reject the null hypothesis and conclude that there is insufficient evidence to show that the number of customers does not follows a uniform distribution.

Answer:.67

Step-by-step explanation:

Answer:

a. The probability x = 2 cents = 7/22

b. The probability x = 6 cents = 35/66

c. The probability x = 10 cents = 5/33

d. The probability x = 11 cents= 28/33

e. The probability x = 15 cents = 20/33

f. The probability x = 20 cents = 14/33

g. The expected value of x = 5.9

Step-by-step explanation:

This is a binomial probability distribution. The number of trials is known .

a. The probability x = 2 cents.

Probability ( X=2) P( selecting 2 dimes)= 7C2 / 12c2

                                                    = 21 / 66 = 7/22

b. The probability x = 6 cents.

Probability ( X=6) P( selecting a nickel and a dime)= 5C1 * 7C1/ 12c2

                                                    = 5*7 / 66 = 35/66

c. The probability x = 10 cents.

Probability ( X=10) P( selecting two nickels )= 5C2 / 12c2)

                                                    = 10/ 66 = 5/33

d. The probability x = 11 cents.

Probability ( X=11) P( selecting a penny and a dime)= 8C1 * 7C1/ 12c2)

                                            = 8*7 / 66 = 56/66= 28/33

e. The probability x = 15 cents.

Probability ( X=15) P( selecting a penny and a nickel)= 8C1 * 5C1/ 12c2)

                                            = 8*5 / 66 = 40/66= 20/33

f. The probability x = 20 cents.

Probability ( X=20) P( selecting 2 pennies )= 8C2 / 12c2)

                                                = 28 / 66 = 14/33

g. The expected value of x.

E(X) = np

E(X) = 2 * (8C2+ 5C2+ 7C2)/(8+5+7) = 2( 28+10+21)/20

=2(59)/20= 5.9

Answer:

3n +3

Step-by-step explanation:

7n-(4n-3)

Distribute the minus sign

7n -4n +3

3n +3

Answer:

  2/5

Step-by-step explanation:

  f(x) = 2(5/2)^-x = 2(2/5)^x

The multiplicative rate of change is the base of the positive exponent, 2/5.

Answer:

a≥0

Step-by-step explanation:

a-82≥-82

a≥-82+82

a≥0

Answer:

x > -7/3

Step-by-step explanation:

-3x+8 < 15

Subtract 8 from each side

-3x+8-8 < 15-8

-3x < 7

Divide by 3 remembering to flip the inequality

-3x/-3 > 7/-3

x > -7/3

Answer:

[tex]x <-\frac{7}{3}[/tex]

First find the critical points of f :

[tex]f(x,y)=2x^2+3y^2-4x-5=2(x-1)^2+3y^2-7[/tex]

[tex]\dfrac{\partial f}{\partial x}=2(x-1)=0\implies x=1[/tex]

[tex]\dfrac{\partial f}{\partial y}=6y=0\implies y=0[/tex]

so the point (1, 0) is the only critical point, at which we have

[tex]f(1,0)=-7[/tex]

Next check for critical points along the boundary, which can be found by converting to polar coordinates:

[tex]f(x,y)=f(10\cos t,10\sin t)=g(t)=295-40\cos t-100\cos^2t[/tex]

Find the critical points of g :

[tex]\dfrac{\mathrm dg}{\mathrm dt}=40\sin t+200\sin t\cos t=40\sin t(1+5\cos t)=0[/tex]

[tex]\implies\sin t=0\text{ OR }1+5\cos t=0[/tex]

[tex]\implies t=n\pi\text{ OR }t=\cos^{-1}\left(-\dfrac15\right)+2n\pi\text{ OR }t=-\cos^{-1}\left(-\dfrac15\right)+2n\pi[/tex]

where n is any integer. We get 4 critical points in the interval [0, 2π) at

[tex]t=0\implies f(10,0)=155[/tex]

[tex]t=\cos^{-1}\left(-\dfrac15\right)\implies f(-2,4\sqrt6)=299[/tex]

[tex]t=\pi\implies f(-10,0)=235[/tex]

[tex]t=2\pi-\cos^{-1}\left(-\dfrac15\right)\implies f(-2,-4\sqrt6)=299[/tex]

So f has a minimum of -7 and a maximum of 299.

Answer:

15.8 sq. in. of paper will be required.

Step-by-step explanation:

The problem is that a drinking cup does not have a cover, so only the lateral surface area counts.

I.e. We need only the first term.

A = pi r l = pi * 1.5 * sqrt(3^2+1.5^2)

= 15.81 sq. in.

Answer: Midline equation: y = -7

Step-by-step explanation: This function is a sinusoidal function of the form:

y = a.cos(b(x+c))+d

Midline is a horizontal line where the function oscillates above and below.

In the sinusoidal function d represents its vertical shift. Midline is not influenced by any other value except vertical shift. For that reason,

Midline, for the function: [tex]h(x) = -4cos(5x-9) - 7[/tex] is y=d, i.e., [tex]y=-7[/tex]

Answer:

y=-7

Step-by-step explanation:

Answer:

The answer is in the photo below. The interval is (-pi, pi) and the function is y = tanx.

Answer:

Step-by-step explanation:

Interesting problem.

At 6<x<8,

f(x) = x-7

at 5<x<8

g(x) = (15-x)/2

=>

y(x)

= f(x)*g(x)

= (x-7)(15-x)/2

= (x^2+22x-105)/2

differentiate y(x) with respect to x,

y'(x) = -x+11

at x = 7,

y'(7) = -(7) + 11 = 4

Answer:

300 SF

Step-by-step explanation:

just took the test

Answer:

(-1,0) and (0,-8)

Step-by-step explanation:

Hey there!

Well first we’ll graph -8x - y = 8,

Look at the image below

By lookig at the image below we can tell the 2 points are at,

(-1,0) and (0,-8)

Hope this helps :)

Answer:

(C) A reflection across a horizontal line and a horizontal translation

Step-by-step explanation:

We can see that, near the x-axis, these shapes are 3 y values away from the x-axis, meaning that if we reflect one over the x-axis we will be at the same y values as the other shape.

Reflecting these points shows that we’ve got the same shape, just skewed the one side. We can then translate this shape horizontally to get it to where we want it.

Hope this helped!

Answer:

$3870

Step-by-step explanation:

Hello, the initial deposit is $1000.

After one year, we will get 1000 + 7%*1000= 1000 * ( 1+7%) = 1000 * (1+0.07)

= 1000 * 1.07

And we want to compound it so the second year we will get

[tex]1000 * 1.07 * 1.07 = 1000 * 1.07^2[/tex]

And after n years, we will get

[tex]1000 * 1.07^n[/tex]

In that example, we want to know how much we will get after 20 years, so this is:

[tex]1000 * 1.07^{20}=3869.684462...[/tex]

Thank you.

When interest is compounded, it means that both the interest and the amount deposited will earn interest.

We are to determine the future value of $1000 with annual compounding.

The formula for calculating future value:

FV = P (1 + r)^n

FV = Future value  

P = amount deposited = $1000

R = interest rate = 7%

N = number of years = 20

$1000 x ( 1.07)^20 = $3,869.68

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Answer:

Step-by-step explanation:

Form a set of values we get

n = 17

And with the help of a calculator

μ₀ = 438,47

σ  = 14,79

Normal Distribution is :  N ( 438,47 ; 14,79 )

c)

CI = 95 % means  α = 5 %    α/2 = 2,5 %    α/2 = 0,025

and as n < 30  we should use t-student distribution with n -1 degree of freedom  df = 16.  t score for 0,025 and 16 s from t-table 2,120

By definition:

CI = [  μ₀  ±  t α/2 ; n-1 * σ/√n ]

CI = [  μ₀  ± 2,120* 14,79/√17 ]

CI = [  μ₀  ±  7,60 ]

CI = [ 438,47 ± 7,60 ]

CI = [  430,87 ; 446,07 ]

95% confidence interval for true average degree of polymerization is  [430.87 ; 446.07] and this interval suggest that 441 is a plausible value for true average degree of polymerization and also this interval does not suggest that 451 is a plausible value.

Given :

The total number of values given is, n = 17

Mean, [tex]\mu_0=438.47[/tex]

Standard Deviation, [tex]\sigma = 14.79[/tex]

The normal distribution is given by: N (438.47 ; 14.79)

If Cl  is 95% then [tex]\alpha[/tex] is 5% and [tex]\alpha /2[/tex] is 2.5%

[tex]\alpha /2 = 0.025[/tex]

Now, use t-statistics distribution with (n-1) degree of freedom df = 16

So, the t score for 0.025 and 16 s from t-table 2.120.

[tex]\rm Cl = [\mu_0 \pm t_{\alpha /2};(n-1)\times \dfrac{\sigma}{\sqrt{n} }][/tex]

[tex]\rm Cl = [\mu_0 \pm 2.120\times \dfrac{14.79}{\sqrt{17} }][/tex]

[tex]\rm Cl = [\mu_0 \pm 7.60][/tex]

Cl = [430.87 ; 446.07]

Yes, the interval suggests that 441 is a plausible value for true average degree of polymerization.

No, the interval does not suggest that 451 is a plausible value.

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Answer:

2.7 in²

Step-by-step explanation:

Given that ∆BAC ~ is similar to ∆EDF, the ratio of the area of ∆BAC to the area of ∆EDF = the square of the ratio of their corresponding sides.

Thus, let x be the area of ∆EDF

[tex] \frac{6}{x} = (\frac{3}{2})^2 [/tex]

[tex] \frac{6}{x} = \frac{9}{4} [/tex]

Cross multiply

[tex] x*9 = 4*6 [/tex]

[tex] 9x = 24 [/tex]

[tex] \frac{9x}{9} = \frac{24}{9} [/tex]

[tex] x = 2.67 [/tex]

Area of ∆EDF = 2.7 in²

Answer:

a. False

b. True

c. False

d. False

e.True

f. True

Step-by-step explanation:

The 95% is confidence interval its not a probability estimate. The probability will be different from the confidence interval. Confidence interval is about the population mean and is not calculated based on sample mean. Every confidence interval contains the sample mean. There is 95% confidence that the number of televisions per American household is between 1.15 to 4.20.

Answer:

x = 2

Step-by-step explanation:

This blue line seems to be horizontal, and so a line perpendicular would have to be vertical. The only vertical line that passes through (2, 6) would be x = 2.

The equation of the line perpendicular to the given line and passes through the point (2, 6) is x = 2.

Equation of a line in slope intercept form is y = mx + b, where m is the slope of the line and b is the y intercept, which is the y coordinate of the point where it touches the Y axis.

Given is a line that passes through the points (-8, -4) and (8, -4).

This line is parallel to the X axis.

A line parallel to X axis has the equation y = b.

The y coordinate is -4 throughout the line.

So equation of the line is y = -4.

A line perpendicular to the given line will be parallel to Y axis.

Parallel lines to Y axis has the equation of the form x = a.

Line passes through the point (2, 6).

x coordinate will be 2 throughout.

So the equation of the perpendicular line is x = 2.

Hence the required equation is x = 2.

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The correct answer is D. Both A and B

Explanation:

Bartering is an economic system in which products are directly exchanged for other products. For example, a pound of oranges is exchanged for a pound of rice. Due to this, in bartering, there is no money or elements such as coins or bills that represent the value of products or services. This system has both advantages and disadvantages in comparison to the use of money.

In terms of disadvantages, bartering implies individuals need products or services they can use to exchange, which might not be possible for all individuals as not all individuals might produce a product or have a product other are interested in. Also, in bartering the value of products varies, for example, a pound of blueberries can be equal to a pound of rice, three pounds of rice, or even half pound of rice, as values change according to the situation of those participating in the exchange. This means, in bartering the value fluctuates and it is more difficult to agree on the value of something, which does not occur if money is used as each product has a defined price which might just vary slightly. According to this, options A and B are advantages of money over bartering.

Answer:

This is a right-tailed test because a direction is specified. The population parameter is greater than the specified value.

Step-by-step explanation:

The hypothesis testing technique is used to test an assumption regarding population parameter. Null hypothesis is a statement that is to be tested against the alternative hypothesis and then decision is taken whether to accept or reject the null hypothesis. A right tailed test is where the most of data is in the right side. This is one tailed test where the direction is specified.

Answer:

1. a. tobt = -4.73

2. b. 9

3. a. +- 2.162

4. d. Reject H0; stress affects the menstrual cycle.

Step-by-step explanation:

The degrees of freedom is number of independent variable factors that affect the range of parameters. The degrees of freedom is the calculation of number values that are free to vary. The degrees of freedom is calculated by N-1. Standard error is the estimated deviation of standard deviation from its sample mean distribution. The null hypothesis is rejected or accepted on the basis of level of significance. When the p-value is greater than level of significance we fail to reject the null hypothesis and null hypothesis is then accepted.

In terms of the trigonometric ratios for ΔABD, what is the length of line segment BD?

Answer:

[tex] BD = c*sin(A) [/tex]

[tex] BD = c*cos(B) [/tex]

[tex] BD = b*tan(A) [/tex]

Step-by-step explanation:

∆ABD is a right triangle.

Recall: trigonometric ratios of any right triangle can easily be understood or remembered with the acronym, SOHCAHTOA.

SOH => sin(θ) = opposite/hypotenuse

CAH => Cos(θ) = adjacent/hypotenuse

TOA = tan(θ) = opposite/adjacent

Thus, the length of segment BD, in terms of trigonometric ratios for ∆ABD can be done as follows:

Let BD = x

AB = c

AD = b

=>The sine ratio for the length of line segment BD = x, using SOH.

θ = A

Opposite = DB = x

hypotenuse = AB = c

[tex] sin(A) = \frac{x}{c} [/tex]

Make x the subject of formula.

[tex] c*sin(A) = x [/tex]

[tex] BD = x = c*sin(A) [/tex]

=>The Cosine ratio for the length of line segment BD = x, using CAH

θ = B

Adjacent = DB = x

hypotenuse = AB = c

[tex] cos(B) = \frac{x}{c} [/tex]

Make x the subject of formula.

[tex] c*cos(B) = x [/tex]

[tex] BD = x = c*cos(B) [/tex]

=>The Tangent ratio for the length of line segment BD = x, using TOA

θ = A

Adjacent = DB = x

hypotenuse = AD = b

[tex] tan(A) = \frac{x}{b} [/tex]

Make x the subject of formula.

[tex] b*tan(A) = x [/tex]

[tex] BD = x = b*tan(A) [/tex]

Answer:

A Maybe

Step-by-step explanation:

Cogntive identification

Unable to answer mathematically or analytically

The Plan of the solid shape is shown by : (A)

A solid shape can be defined as a shape that possesses three dimensions. that is to say they are three dimensional shapes.

A solid shape has both length, width and height. They are more tangible and look physical than two dimensional shape.

solid shapes can take up space in the universe because they are more tangible and realistic.

In conclusion, the Plan of the solid shape is shown by : (A)

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