Water is flowing into a tank at a rate of 20 cm3/min. At the start, there is 250 cm3 of water in the tank.
(i) How much water will be in the tank after 30 minutes?
(ii) Find the time when there is 1210 cm3 of water in the tank.

The length of the confidence interval is the margin of error, which is the ratio of the standard deviation and the square root of sample size. Hence, to reduce the length of confidence interval by half, Quadruple the sample size.

Recall :

Evaluating an hypothetical scenario :

Let standard deviation, σ = 2

Sample size = 50

Margin of Error = 2/√50 = 0.554

Using Quadruple of the sample size : (50 × 4) = 200 samples

(0.227 ÷ 0.554) = 0.5

Therefore, increasing the sample size, reduces the margin of error. Hence, using quadruple the sample size, will reduce the margin of error by half.

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Answer:

[tex]f(x) = x^4 + 9x^3 + 27x^2 + 27x[/tex]

Step-by-step explanation:

Zeros of a function:

Given a polynomial f(x), this polynomial has roots [tex]x_{1}, x_{2}, x_{n}[/tex] such that it can be written as: [tex]a(x - x_{1})*(x - x_{2})*...*(x-x_n)[/tex], in which a is the leading coefficient.

- 3 as a zero of multiplicity 3

So

[tex]f(x) = (x - (-3))^3 = (x + 3)^3 = x^3 + 9x^2 + 27x + 27[/tex]

0 as a zero of multiplicity 1.

So

[tex]f(x) = x(x^3 + 9x^2 + 27x + 27) = x^4 + 9x^3 + 27x^2 + 27x[/tex]

(Use 1 for the leading coefficient.)

Multiply the polynomial by 1, so it stays the same. The polynomial in expanded form is:

[tex]f(x) = x^4 + 9x^3 + 27x^2 + 27x[/tex]

Answer:

your answer calculated would be: x(30x^4 + 15xy^2 + y)

Step-by-step explanation:

i used math-way it's a really useful online calculator

9514 1404 393

Answer:

  see attached

Step-by-step explanation:

A graphing calculator can do a nice job of showing you what the graph looks like.

The initial factor of 4 is the value when x=0, the y-intercept. The base of 2 tells you the function value is multiplied by 2 for each unit of x to the right, and divided by 2 for each unit of x to the left. (The curve quickly goes off the top of the graph.)

The horizontal asymptote is y=0, as it is for all exponential functions (that have not been translated).

No. The F test has a requirement that samples be from the normally distributed populations, regardless of how large the samples are.

The F-test simply shows whether the variances that are in the numerator and the denominator are equal. The F-test can be applied on a large sampled population.

One main assumption of the F test is that the populations where the two samples are drawn are normally distributed.

Regarding the question, it's important to note that when using the F test with these​ data, it's not correct to reason that there is no need to check for "normality".

It should be noted that the F test has a requirement that samples are from the normally distributed populations, regardless of how large such samples are.

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Answer:

Step-by-step explanation:

in this specific case the two legs are congruent:

b = 18

For the Pythagorean theorem

a = √ 2 * 18^2 = 18√2

Answer:

15.924 feets

Step-by-step explanation:

The height I'd the flagpole can be obtained using trigonometry ;

Solution triangle has been attached below,

The height, h of flagpole

Tan θ = opposite / Adjacent = h / 12

Tan 53 = h / 12

h = 12 * tan 53

h = 15.924

9514 1404 393

Answer:

  111 1/9 pounds

Step-by-step explanation:

The given relationship is ...

  delivered = ground × (1 -10%)

Then ...

  ground = delivered/0.90 = 100 lb/0.90 = 111 1/9 lb

It is necessary to grind 111 1/9 pounds of grain to have exactly 100 lb after a 10% payment.

Answer:

34%

Step-by-step explanation:

Given that the distribution of daily light bulb request replacement is approximately bell shaped with ;

Mean , μ = 45 ; standard deviation, σ = 3

Using the empirical formula where ;

68% of the distribution is within 1 standard deviation from the mean ;

95% of the distribution is within 2 standard deviation from the mean

Lightbulb replacement numbering between ;

42 and 45

Number of standard deviations from the mean /

Z = (x - μ) / σ

(x - μ) / σ < Z < (x - μ) / σ

(42 - 45) / 3 = -1

This lies between - 1 standard deviation a d the mean :

Hence, the approximate percentage is : 68% / 2 = 34%

Answer:

Each chocolate truffle is $2.125

Step-by-step explanation:

Honestly, I'm not 100% sure if this is correct, and I am truly sorry if this is wrong, but its worth a try :)

Answer:

9

Step-by-step explanation:

f(x) = 2x+9

f(x) = 27

so, you get:

2x+9=27

2x=18

x=9

9514 1404 393

Answer:

  y = 2x +4

Step-by-step explanation:

The slope can be found using the slope formula:

  m = (y2 -y1)/(x2 -x1)

  m = (12 -(-6))/(4 -(-5)) = 18/9 = 2

The y-intercept can be found from ...

  b = y -mx

  b = 12 -(2)(4) = 4

Then the slope-intercept equation for the line is ...

  y = mx +b

  y = 2x +4

Answer:

y=2x+4

Step-by-step explanation:

Hi there!

We want to find the equation of the line that passes through the points (-5, -6) and (4, 12)

The most common way to write the equation of the line is in slope-intercept form, which is y=mx+b, where m is the slope and b is the y intercept

First, let's find the slope of the line

The formula for the slope calculated from two points is [tex]\frac{y_2-y_1}{x_2-x_1}[/tex], where ([tex]x_1[/tex], [tex]y_1[/tex]) and ([tex]x_2[/tex], [tex]y_2[/tex]) are points

We have everything needed to calculate the slope, but let's label the values of the points to avoid any confusion

[tex]x_1[/tex]=-5

[tex]y_1[/tex]=-6

[tex]x_2[/tex]=4

[tex]y_2[/tex]=12

Now substitute into the formula (remember: the formula has SUBTRACTION in it)

m=[tex]\frac{y_2-y_1}{x_2-x_1}[/tex]

m=[tex]\frac{12--6}{4--5}[/tex]

Simplify

m=[tex]\frac{12+6}{4+5}[/tex]

Add

m=[tex]\frac{18}{9}[/tex]

Divide

m=2

So the slope of the line is 2

Here is the equation so far:

y=2x+b

We need to find b

As the line will pass through both (-5, -6) and (4, 12), we can use the values of either one to solve for b

Let's take (4, 12) for instance

Substitute 4 as x and 12 as y

12=2(4)+b

Multiply

12=8+b

Subtract 8 from both sides

4=b

Substitute 4 as b in the equation

y=2x+4

Hope this helps!

Answer:

your answer will be Option D

Step-by-step explanation:

log 10

Answer:

y = 2x - 7

Step-by-step explanation:

Parallel lines have the same slope so only the y-intercept is different. Therefore nothing is changed between the two equations except the y-intercept is -7.

9514 1404 393

Answer:

  A.  96

Step-by-step explanation:

The surface area is the sum of the areas of the two triangular bases and the areas of the three rectangular lateral faces.

  A = 2(1/2)bh + PH

where b is the base of the triangle, h is its height, P is the perimeter of the triangle, and H is the height of the prism.

  A = (3 cm)(4 cm) +(3 +4 +5 cm)(7 cm) = 12 cm² +84 cm²

  A = 96 cm²

The surface area of the triangular prism is 96 square cm.

Answer:

FALSE.The ratio of the volumes of two similar solid polyhedra is equal to the square of the ratio between their edges. This statement is false. A polyhedron is a shape that has no gaps between their edges or vertices.

Answer:

it's false

~~~~~~~~~~~

Answer:

Step-by-step explanation:

whitch answer how do you want us to answer

Answer:

AC is about 4.29

Step-by-step explanation:

we need to use simple trigonometry for this problem

the tangent of an angle is the ratio between the opposite side and the adjacent side

so the tangent of the angle 35º is BC / AC

tan(35) is about 0.7

this means that BC / AC = 0.7

we know BC is 3

so 3 / AC = 0.7

3 = 0.7(AC)

AC is about 4.29

Answer:

F statistic = 2.124

Pvalue = 0.0546

A. Fail to reject the null hypothesis. There is insufficient evidence to to support the claim that those given a sham treatment have reductions that vary more than those treated with magnets

Step-by-step explanation:

H0 : pain reduction is the same

H1 : pain reduction is varies more with sham.

Sham n= 20 x=0.41 s=1.37

Magnet n= 20 x =0.46 s= 0.94

α - level = 0.05

Using the Ftest statistic

Ftest = larger sample variance / smaller sample variance

Ftest = s1² / s2² = 1.37² / 0.94² = 1.8769 / 0.8836 = 2.124

The degree of freedom :

Numerator = n - 1 = 20 - 1 = 19

Denominator = n - 1 = 20 - 1 = 19

Pvalue(2.124, 19, 19) = 0.0546

Since ;

Pvalue > α ; WE fail to reject the Null ; Result is not significant

Step-by-step explanation:

Download gauthmath it will help

Answer:

answers in the explanation cz I'm too lazy to type :(

not entirely sure tho

Step-by-step explanation:

w²+2w-42=0

*quadratic formula*

w= -1+ square root 43 m

or w= -1- square root 43 m

then since the length is 2m more than w

add 2 to both answers

l= 1+ square root 43 m

l=1- square root 43 m

9514 1404 393

Answer:

Step-by-step explanation:

Given:

  a rectangular patio of width w meters, length w+2 meters, and area 42 m²

Find:

  width and length

Solution:

The area is ...

  A = LW

  42 = w(w +2)

  43 = w² +2w +1 . . . . . . add 1 to complete the square

  √43 = w+1

  w = √43 -1 ≈ 5.557 . . . meters

  l = w+2 = √43 +1 ≈ 7.557 . . . meters

The width and length of the patio are 5.557 m and 7.557 m, respectively.

First check the characteristic solution. The characteristic equation to this DE is

r ² - r = r (r - 1) = 0

with roots r = 0 and r = 1, so the characteristic solution is

y (char.) = C₁ exp(0x) + C₂ exp(1x)

y (char.) = C₁ + C₂ exp(x)

For the particular solution, we try the ansatz

y (part.) = (ax + b) exp(x)

but exp(x) is already accounted for in the second term of y (char.), so we multiply each term here by x :

y (part.) = (ax ² + bx) exp(x)

Differentiate this twice and substitute the derivatives into the DE.

y' (part.) = (2ax + b) exp(x) + (ax ² + bx) exp(x)

… = (ax ² + (2a + b)x + b) exp(x)

y'' (part.) = (2ax + 2a + b) exp(x) + (ax ² + (2a + b)x + b) exp(x)

… = (ax ² + (4a + b)x + 2a + 2b) exp(x)

(ax ² + (4a + b)x + 2a + 2b) exp(x) - (ax ² + (2a + b)x + b) exp(x)

= x exp(x)

The factor of exp(x) on both sides is never zero, so we can cancel them:

(ax ² + (4a + b)x + 2a + 2b) - (ax ² + (2a + b)x + b) = x

Collect all the terms on the left side to reduce it to

2ax + 2a + b = x

Matching coefficients gives the system

2a = 1

2a + b = 0

and solving this yields

a = 1/2, b = -1

Then the general solution to this DE is

y(x) = C₁ + C₂ exp(x) + (1/2 x ² - x) exp(x)

For the given initial conditions, we have

y (0) = C₁ + C₂ = 6

y' (0) = C₂ - 1 = 5

and solving for the constants here gives

C₁ = 0, C₂ = 6

so that the particular solution to the IVP is

y(x) = 6 exp(x) + (1/2 x ² - x) exp(x)

Answer:

[tex]\approx 0.482659[/tex]

Step-by-step explanation:

The experimental probability is the chance of an event happening based on data, or rather the experiment results, and not on a theoretical calculation. In essence, a theoretical calculation can be described by the following formula:

[tex]\frac{desired}{total}[/tex]

However, the experimental probability can be described with the following formula:

[tex]\frac{number\ of\ desired\ outcomes}{number\ of \ trials}[/tex]

The number of trials is the sum of the number of outcomes. In this case, the desired outcome is tails. Therefore, the experimental probability can be described using the following formula:

[tex]\frac{tails}{total}[/tex]

One can also rewrite the formula as the following. This is because the total is the sum of the number of the two outcomes:

[tex]\frac{tails}{heads+tails}[/tex]

Substitute,

[tex]\frac{167}{167+179}[/tex]

Simplify,

[tex]\frac{167}{346}[/tex]

Rewrite as a decimal:

[tex]\approx 0.482659[/tex]

Answer:

(6, -9)

Step-by-step explanation:

let: 8x + 2y = 30 be equation (a).

7x + 2y = 24 be equation (b).

[tex]{ \bf{equation \: (a) - equation \: (b) : }}[/tex]

[tex] (8 - 7)x + (2 - 2)y = (30 - 24) \\ x + 0y = 6 \\ x = 6[/tex]

substitute for x in equation (a):

[tex] (8 \times 6) + 2y = 30 \\ 48 + 2y = 30 \\ y = - 9[/tex]

Answer:

option 2

Step-by-step explanation:

9514 1404 393

Answer:

  $181.81

Step-by-step explanation:

  (2215 mi)/(38 mi/gal)×($3.119/gal) = $181.8048

We round this up so that we have enough gas to get there. We don't want to have to walk the last 309 feet to the destination.

  It will cost $181.81 to get to the destination.

Answer:

√65

Step-by-step explanation:

(-6,4) (-5,-4)

√(x2 - x1)² + (y2 - y1)²

√[-5 - (-6)]² + (-4 - 4)²

√(1)² + (-8)²

√1 + 64

√65

Answer:

1: A=1

2: -3

3: C

Step-by-step explanation:

1: If 3x+4 is a factor, then -4/3 is equal to x. Substitute it in for x and solve for a.  This gives us A=1.

For the commenter not understanding how I got -4/3: 3x+4 being a factor means that it equals 0. It might help you understand this if you remember that after factoring, like I did for 38 in my photo, we take expressions like x-4 and set them equal to 0 to get x=4, a solution. So, subtract 4 from both sides to get 3x=-4, then divide both sides by 3 to get x alone. Thus, x=-4/3.

2: To find the sum, we first need to find the two solutions. We can factor to get (x+7)(x-4). This gives us x=-7 and x=+4. The solution of these two would be (-7)+4 is -3.

3: B is a close answer, but the signs are wrong on the bottom. Factoring the question would give us 2(x-2) / 2(x^2-x-2). Factoring that equation is 2(x-2) / 2(x+1)(x-2). Simplifying this gives us 1 / x+1.

Sorry for the bad penmanship, I wanted to make it a little clearer for you! I really hope I helped! :)

Answer:

b

Step-by-step explanation:

The value of x 85.

The arc period of a circle can be calculated with the radius and relevant perspective using the arc period method.

⇒angle= arc/radius

⇒  107°=arc/7

⇒ arc =1o7°*7

⇒arc=107π/180° *7

⇒arc = 85

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