g You measure 40 textbooks' weights, and find they have a mean weight of 73 ounces. Assume the population standard deviation is 11.7 ounces. Based on this, construct a 99% confidence interval for the true population mean textbook weight.

Answer:

Explained below.

Step-by-step explanation:

According to the Central limit theorem, if from an unknown population large samples of sizes n > 30, are selected and the sample proportion for each sample is computed then the sampling distribution of sample proportion follows a Normal distribution.

The mean of this sampling distribution of sample proportion is:

 [tex]\mu_{\hat p}= p[/tex]

The standard deviation of this sampling distribution of sample proportion is:

 [tex]\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}[/tex]

(a)

The sample selected is of size n = 450 > 30.

Then according to the central limit theorem the sampling distribution of sample proportion is normally distributed.

The mean and standard deviation are:

[tex]\mu_{\hat p}=p=0.75\\\\\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.75(1-0.75)}{450}}=0.0204[/tex]

So, the sampling distribution of sample proportion is [tex]\hat p\sim N(0.75,0.0204^{2})[/tex].

(b)

Compute the probability that the sample proportion will be within 0.04 of the population proportion as follows:

[tex]P(p-0.04<\hat p<p+0.04)=P(\frac{-0.04}{0.0204}<\frac{\hat p-p}{\sigma_{\hat p}}<\frac{0.04}{0.0204})[/tex]

                                          [tex]=P(-1.96<Z<196)\\=P(Z<1.96)-P(Z<-1.96)\\=0.975-0.025\\=0.95[/tex]

Thus, the probability that the sample proportion will be within 0.04 of the population proportion is 0.95.

(c)

The sample selected is of size n = 200 > 30.

Then according to the central limit theorem the sampling distribution of sample proportion is normally distributed.

The mean and standard deviation are:

[tex]\mu_{\hat p}=p=0.75\\\\\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.75(1-0.75)}{200}}=0.0306[/tex]

So, the sampling distribution of sample proportion is [tex]\hat p\sim N(0.75,0.0306^{2})[/tex].

(d)

Compute the probability that the sample proportion will be within 0.04 of the population proportion as follows:

[tex]P(p-0.04<\hat p<p+0.04)=P(\frac{-0.04}{0.0306}<\frac{\hat p-p}{\sigma_{\hat p}}<\frac{0.04}{0.0306})[/tex]

                                          [tex]=P(-1.31<Z<196)\\=P(Z<1.31)-P(Z<-1.96)\\=0.9049-0.0951\\=0.8098\\\approx 0.81[/tex]

Thus, the probability that the sample proportion will be within 0.04 of the population proportion is 0.81.

(e)

The probability that the sample proportion will be within 0.04 of the population proportion if the sample size is 450 is 0.95.

And the probability that the sample proportion will be within 0.04 of the population proportion if the sample size is 200 is 0.81.

So, there is a gain in precision on increasing the sample size.

Answer:

C

Step-by-step explanation:

Answer:

-2&-4

Step-by-step explanation:

-5x-6y=-8

it is a quadratic equation:

-5x-6y+8=0

(x-2)(x-4)

cross multiple and you'll get

-5x-6y+8=0

Answer:

-2

Step-by-step explanation:

Bc÷2a

5×-4÷2×5

-20÷10

-2

The value of the expression bc ÷ 2a will be negative 2.

The analysis of mathematical representations is algebra, and the handling of those symbols is logic.

A principle that specifies the right procedure to follow while calculating a mathematical equation is known as the activities to be conducted.

PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction.

The value of the variable expression when a = 5, b = 5, and c = -4.

The expression is given below.

⇒ bc ÷ 2a

Substitute the value of the variable a = 5, b = 5, and c = -4.

⇒ 5 × (-4) ÷ 2 × 5

Simplify the expression, then the value of the expression will be

⇒ - 20 ÷ 10

⇒ - 2

The value of the expression will be negative 2.

More about the Algebra link is given below.

https://brainly.com/question/953809

#SPJ2

Okay I will help you.

9 7/9 simplified and in mixed number form.

PLEASE MARK ME BRAINLIEST IF I'M RIGHT!! THANKS

Answer:

1+8i

Step-by-step explanation:

Given, complex numbers z = 9 – 2i and zw = 25 + 70i. w = 1 + 8i.

In mathematics, a complex number is an element of a number system that contains the real numbers and a specific element denoted i, called the imaginary unit, and satisfying the equation i² = −1.

= (9 - 2i)(1 + 8i)

= 9 + 72i - 2i -16i^2

= 9 + 70i + 16  (i^2 = -1)

= 25 + 70i

Learn more about complex numbers here

https://brainly.com/question/10251853

#SPJ2

Answer:

A' (4,4), B' (5,7), C' (9,7)

Step-by-step explanation:

Answer:

First table's unit rate is -1.6

Second table's unit rate is  3.5

Step-by-step explanation:

First table:

[tex]\Delta y/\Delta x =(-16--8)/(10-5)= -8/5[/tex]

and this is constant for any pair of (x, y) values of the table.

So the unit rate is: -8/5 = -1.6

Second table:

[tex]\Delta y/\Delta x =(21-7)/(6-2)=14/4=7/2[/tex]

and the rate is constant for any pair of (x, y) values of the table.

So the unit rate is: 7/2 = 3.5

Answer:

oy-5=1 ( x-30)

Step-by-step explanation:

jernardia is dumb as heck

Answer:

212

Step-by-step explanation:

3 goes into 6 = 2 times

3 goes into 3 = 1 time

3 goes into 6 = 2 times

2 → 1 → 2 = 212

Answer:

= 4.9*10^-3

Step-by-step explanation:

Hope it helpzzz

Answer:

36 lemons

Step-by-step explanation:

You would need 36 lemons for 15 quarts of water because for every 5 quarts of water, it takes 12 lemons. 15 quarts is 3x5 quarts, and 12x3=36 lemons. Hope it helps!

Answer:

A. 31 cm

Step-by-step explanation:

Hopefully its right :)

Answer:

[tex]\mathbf{\int \int _R \ 4xy e^{x^2 \ y} \ dA = 2 (e^7 -8)}[/tex]

Step-by-step explanation:

Given that:

[tex]\int \int _R 4xye^{x^2 \ y} \ dA, R = [0,1]\times [0,7][/tex]

The rectangle R = [0,1] × [0,7]

R = { (x,y): x ∈ [0,1] and y ∈ [0,7] }

R = { (x,y): 0 ≤ x ≤ 1 and 0 ≤ x ≤ 7 }

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = \int^{7}_{0}\int^{1}_{0} 4xye^{x^2 \ y} \ dx dy[/tex]

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = \int^{7}_{0} \begin {bmatrix} ye^{yx^2} \dfrac{4}{2y} \end {bmatrix}^1 _ 0 \ dy[/tex]

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = \int^{7}_{0} \begin {bmatrix} ye^{y1^2} \dfrac{4}{2y} - ye^{y0^2} \dfrac{4}{2y} \end {bmatrix}\ dy[/tex]

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = \int^{7}_{0} \dfrac{4}{2}(e^y -1) \ dy[/tex]

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = \dfrac{4}{2}[e^y -1]^7_0 \ dy[/tex]

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = 2 [(e^7 -7)-(e^0 -0)][/tex]

[tex]\int \int _R \ 4xy e^{x^2 \ y} \ dA = 2 [(e^7 -7)-1][/tex]

[tex]\mathbf{\int \int _R \ 4xy e^{x^2 \ y} \ dA = 2 (e^7 -8)}[/tex]

Answer: For the last answer its actually less than

Step-by-step explanation: Instead of you put less than you put Its less than or equal to which is wrong.

Answer: R=8

Step-by-step explanation: R-7=1, R+7=1+7, R=8.

Answer:

1. The expected pay-out on each policy is 250 * 1/90 + 12000 * 1/100 + 17000 * 1/400 = $165.  So that's what the premium would have to be in order to get a profit of 0.

2. The profit per policy is the premium the company receives minus the expected payout = 350 - 165 = $185.

3. The expected profit on 375 policies would be 375 * 185 = $69375

Step-by-step explanation:

Answer: B (4/5)

Step-by-step explanation:

SOH CAH TOA

T = opposite/hypotenuse

Opposite = 32

Hypotenuse = 40

Simplify 32/40 = 4/5

Answer:

my GUESS would be A

Step-by-step explanation:

because 2+4=6

but also kinda slow soo.....

Answer:was it 3?

Step-by-step explanation:

thats wat i got not sure tho

Answer:

1 rupee=100 paisa

so, 20 paisa:2000 rupees

=>20 paisa:2000×100

=>1:10000.

4 liters of 20% solution are needed to get a 14% solution.

Suppose x liters of 20% solution is needed to get a 14% solution.

The solution is a homogenous mixture of two or more substances in relative amounts.

So, according to the question

Final concentration of solution = 14%

So, 12% of 12  + 20% of x = 14% of (12+x)

12*12/100 + 20*x/100 = 14*(12+x)/100

144 + 20x = 168 + 14x

6x =24

x=4

4 liters of 20% solution is needed to get a 14% solution.

Therefore, 4 liters of 20% solution is needed to get a 14% solution.

To get more about mixtures and alligations visit:

https://brainly.com/question/26413176

Answer:

The answer is going to be option 1.

Step-by-step explanation:

The answer you get from multiply an number by itself is a perfect square.

Answer:

8×8 =8^2=64 (perfect square)

Step-by-step explanation:

64 is a perfect square because 8^2 =8×8 =64

Answer:it said i was wrong and the correct answer should have been -6 3/10

Step-by-step explanation:

The total change in weight of the sculpture after [tex]3\frac{1}{2}[/tex] hours is, [tex]\bold{-6\frac{3}{10}}[/tex] pounds.

"The rate of change function is the rate at which one quantity is changing with respect to another quantity."

Given: The weight of an ice sculpture changes [tex]-1\frac{4}{5}[/tex] pounds every hour.

We need to find the total change in weight of the sculpture after [tex]3\frac{1}{2}[/tex] hours.

i.e., the rate of change of an ice sculpture per hour is -1 4/5 pound.

Total change in weight of the sculpture after t hours

= change in the weight of the sculpture per hour × t

= [tex](-1\frac{4}{5}) \times (3\frac{1}{2} )[/tex]

= [tex](-\frac{9}{5} ) \times (\frac{7}{2} )[/tex]

= [tex]-\frac{63}{10}[/tex]

= [tex]\bold{-6\frac{3}{10}}[/tex] pounds

Therefore, the total change in weight of the sculpture after 3 1/2 hours is, [tex]\bold{-6\frac{3}{10}}[/tex] pounds.

Learn more about rate of change here:

https://brainly.com/question/11499305

#SPJ2

Answer:

f(10) = 23

Step-by-step explanation:

you plug in 10 for the x in the equation and then solve. So 3 x 10 = 30 then minus 7

Answer:

x=-1

Step-by-step explanation:

Isolate the variable by dividing each side by factors that don't contain the variable.

x=−1

Answer:

can u attach the diagram

Step-by-step explanation:

Answer:

A

Step-by-step explanation:

By solving (x+6)(x-9), we get x^2 - 3x - 54. By looking at our y-intercept, we can see that only option A has the correct intercept.

Answer:

A

Step-by-step explanation: