Oil is pumped continuously from a well at a rate proportional to the amount of oil left in the well. Initially there were 2 million barrels of oil in the well; six years later 1,000,000 barrels remain.

Required:
a. At what rate was the amount of oil in the well decreasing when there were 1,200,000 barrels remaining?
b. When will there be 100,000 barrels remaining?

Mean:

[tex]E(X) = \displaystyle \sum_{x\in\{1,2,3,4\}}x\,P(X=x) = 1\times0.4 + 2\times0.1 + 3\times0.3 + 4\times0.2 = \boxed{2.3}[/tex]

Variance:

[tex]\displaystyle V(X) = E\left((X-E(X))^2\right) = E(X^2) - E(X)^2 \\\\ E(X^2) = \sum_{x\in\{1,2,3,4\}}x^2\,P(X=x) = 1^2\times0.4 + 2^2\times0.1 + 3^2\times0.3 + 4^2\times0.2 = 6.7 \\\\ \implies V(X) = 6.7 - 2.3^2 = \boxed{1.41}[/tex]

Standard deviation:

[tex]\sigma_X = \sqrt{V(X)} = \sqrt{1.41} \approx \boxed{1.19}[/tex]

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

9514 1404 393

Answer:

  OBADR

Step-by-step explanation:

The first two letters are swapped, and the last two letters are swapped.

  BOARD . . . becomes

  OBADR

Correct options are -10 and 10

-7 + (-10² - 19)³/⁴ = 20

-7 + (100 - 19)^3/4 = 20

-7 + (81)^3/4 = 20

-7 + 27 = 20

20 = 20

RHS = LHS

-7 + (10² - 19)^3/4 = 20

-7 + (100 - 19)^3/4 = 20

-7 + (81)^3/4 = 20

-7 + 27 = 20

20 = 20

RHS = LHS

Rest options are incorrect

Answered by Gauthmath must click thanks and mark brainliest

Answer:

B and C, so 10 and -10

Step-by-step explanation:

Answer:

can't understand the language

Answer:

[tex]s=6\sqrt{3}[/tex]

Step-by-step explanation:

In any 30-60-90 triangles, the sides are in ratio [tex]x:x\sqrt{3}:2x[/tex], where [tex]x[/tex] is the side opposite to the 30 degree angle and [tex]2x[/tex] is the hypotenuse of the triangle.

In the given diagram, the hypotenuse is marked as 12 miles. Therefore, the side opposite to the 30 degree angle must be [tex]12 \div 2=6[/tex] miles. The final leg, [tex]s[/tex], must then represent the [tex]x\sqrt{3}[/tex] part of our ratio, hence [tex]\implies \boxed{6\sqrt{3}}[/tex]

Answer:

c.

Step-by-step explanation:

Answer:

1/5

Step-by-step explanation:

I think it's (2,0).

Because u use the slope of line AB to go down from point C until one of the answers are met.

The point on the x-axis that will make the line that passes through point C parallel to line AB is: D. (2, 0).

Slope of AB = -(3/6)

Slope of AB = -1/2

Slope of from point (2, 0) to point C(-2, 2):

Slope = (2 - 0)/(-2 - 2) = 2/-4

Slope = -1/2

Therefore, the point on the x-axis that will make the line that passes through point C parallel to line AB is: D. (2, 0).

Learn more about slope of parallel lines on:

https://brainly.com/question/10790818

9514 1404 393

Answer:

  Amy: $620

  Tom: $400

Step-by-step explanation:

The pay for 40 hours (1 week) is 40 times the pay for 1 hour:

  Amy: 40 × $15.50 = $620 . . . . Amy's pay for 1 week

  Tom: 40 × $10.00 = $400 . . . . Tom's pay for 1 week

We have to figure out what the product of DA is,

[tex]\begin{bmatrix}-1&2&3\\8&-4&0\\6&7&1\\ \end{bmatrix}\begin{bmatrix}1\\3\\5\\ \end{bmatrix}=\begin{bmatrix}a\\b\\c\\ \end{bmatrix}[/tex]

We know that,

[tex]\begin{bmatrix}a&b&c\\d&e&f\\g&h&i\\\end{bmatrix}\begin{bmatrix}x\\y\\z\\\end{bmatrix}=\begin{bmatrix}ax+by+cz\\dx+ey+fz\\gx+hy+iz\\\end{bmatrix}[/tex]

So,

[tex]a=-1\cdot1+2\cdot3+3\cdot5=-1+6+15=20[/tex]

[tex]b=8\cdot1+(-4)\cdot3+0\cdot5=8-12=-4[/tex]

[tex]c=6\cdot1+7\cdot3+1\cdot5=6+21+5=32[/tex]

So the solution is,

[tex]a,b,c=\boxed{20,-4,32}[/tex]

Hope this helps :)

Answer:

Step-by-step explanation:

Let t = 2

h = 122.5 - 4.9·2² = 122.5-19.6 = 102.9

Step-by-step explanation:

Hey there!

From the given figure;

Angle FVT = 43°

VT = 53

Taking Angle FVT as reference angle we get;

Perpendicular (p) = FT = ?

Base (b) = VT = 53

Taking the of tan;

[tex] \tan( \alpha ) = \frac{p}{b} [/tex]

Keep all values and simplify it;

[tex] \tan(43) = \frac{ft}{53} [/tex]

0.932515*53 = FT

Therefore, FT= 49.423.

Hope it helps!

Answer:

A. 49.42

Step-by-step explanation:

tan 43 = FT ÷ VT

0.932515086 = FT ÷ 53

49.42 = FT

Answer:

y=-2x

Step-by-step explanation:

first find the slope: (-2-(-4))/(1-2)=2/-1=-2 so m=-2

now we have y=-2x+b, to find b we plug in any of the points

so the equation is y=-2x

Answer:

18

Step-by-step explanation:

7-5=2

2x9=18

Answer:

In a bag of balls, 1/4th are green, 1/8th are blue, 1/12th are yellow and the remaining 26 are white. How many balls are blue?

There are 4 colours of balls - green, blue, yellow and white.

Add (1/4)+(1/8)+(1/12) = (6/24)+(3/24)+(2/24) = 11/24 so the balance or (24–11)/24 = 13/24 = 26 white. Hence the total number of balls are 2*24 = 48.

Of the 48 balls, green are (1/4)*48 = 12, blue are (1/8)*48 = 6, yellow are (1/12)*48 = 4 and the rest, white are 26.

Check: Total number of balls = 12+6+4+26 = 48

Answer: 6 balls are blue....

Answer:

1250 amps

Step-by-step explanation:

V = 5000 V

R = 4 ohms

Use ohms law: V = IR

5000 =I(4)

I = 1250 amps

Answer:

Lol yu lateee das "who i smoke by yung ace"

Step-by-step explanation:

Answer:

woogle said woo hoo  by rock a teens

Step-by-step explanation:

Answer:

Z = (42-20)/4 = 5.5

Z = X-μ / σ

Step-by-step explanation:

The z-score for the data value of 42 is 5.5.

A z-score is defined as the fractional representation of data point to the mean using standard deviations.

Formula of z-score = (X - μ) / σ

Given,

μ = 20

σ = 4

X = 42

z-score = (X - μ) / σ

Substitute the values,

z-score =  (42-20)/4

z-score = 22/4

z-score =  5.5

Hence, the z-score for the data value of 42 is 5.5.

Learn more about z-score here:

brainly.com/question/13793746

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Answer:

y = 4

Step-by-step explanation:

The ratio of the lengths of the sides of a 30-60-90 triangle is

1 : √3 : 2

The sides in this triangle are in the order:

y : 4√3 : x

y/1 = 4√3/√3

y = 4

Answer:

x>3

Step-by-step explanation:

8x - 2x > 12+ 6

-> 6x > 18

-> x > 3

[tex] \: \: \: \huge \rm{answer: \blue{ \boxed{ \rm{ \pink{x > 3}}}}}[/tex]

➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖

[tex] \huge \blue{ \boxed{ \pink{\boxed{ \rm{ \blue{armed }\: account}}}}}[/tex]

➙[tex] \huge \rm8x-6>12+2x \\ \rm \huge8x-2x>12+6 \\ \huge\rm6x>18 \\ \huge \boxed{\rm{x>3}}[/tex]

➖➖➖➖➖➖➖➖➖➖➖➖➖➖

I hope you understood!✏

➖➖➖➖➖➖➖➖➖➖➖➖➖➖

Step-by-step explanation:

[tex] \huge \boxed{ \boxed{\rm{Hope \: this \: helps}}}[/tex]

The lub is 0.23[tex]\mathbf{\overline{43}}[/tex], while the glb is 0.2

The given set is presented as follows;

E = {0.2, 0.23, 0.234, 0.2343, 0.23434, 0.234343,...}

The least upper bound, lub, of a set, E, is known as the supremum of the set which is the number B such that all x ∈ E are of the value x  ≤ B, while there all y ∈ E has a x ∈ E such that t < x

Therefore;

The supremum, lub of the given set is 0.23[tex]\overline{43}[/tex]

The greatest lower bound, glb, b, also known as the infimum, is defined as follows;

b is the greatest lower bound if for all x ∈ E then x ≥ b

Given that b < t, then where x ∈ E, there exist a x < t

The glb of the given set is 0.2

Learn more about lub, supremum, glb, infimum, here;

https://brainly.in/question/23591741

Answer:

22 weeks

Step-by-step explanation:

Let Suppose if weeks is x

So if we count it:

$40 + $15x = $370

$15x = $330

x = 22 weeks

So, Alan needs 22 weeks to have enough money to buy the new bicycle

Question: -4 + 5x -7 = 10 + 3x -2x

⇒ 5x -11 = 10 + x

⇒ 5x - x = 10+11

⇒ 4x = 21

⇒ x = 21/4

Answer is Option D

x = 21/4

Must click thanks and mark brainliest

Answer: DE = 79

Concept:

Here, we need to know the idea of segment addition postulate.

The Segment Addition Postulate states that given 2 points A and C, a third point B lies on the line segment AC if and only if the distances between the points satisfy the equation AB + BC = AC.

If you are still confused, you may refer to the attachment below for a graphical explanation or tell me.

Solve:

**Disclaimer** I assume that points D, E, F are collinear, thus they would form a segment and F would be the point between D and E. If it was, you may refer to my answers. If it was not, you may tell me and I will redo it.

Given information

DF = 61

EF = 18

Given expression deducted from the segment addition postulate

DE = DF + EF

Substitute values into the expression

DE = (61) + (18)

Simplify by addition

[tex]\boxed{DE=79}[/tex]

Hope this helps!! :)

Please let me know if you have any questions

Answer:

N=18

Step-by-step explanation:

Hope it will help you

If it does pls give me Brainlest

Have a nice day

Answer:

18

Step-by-step explanation:

use the concept of similarity and enlargement.

[tex] \frac{15}{n} = \frac{5}{6 } [/tex]

[tex]n = \frac{15 \times 6}{5} [/tex]

[tex]n = 18[/tex]

Step-by-step explanation:

2997

81

×

37

=2997

it just a simple calculation just multiply the numbers

Answer:

x = 1

y = 2

Step-by-step explanation:

5x + 2y = 9

-5x + 4y = 3

==> 6y = 12 ==> y = 12/6 ==> y = 2.

we replace y by its value in the first or the second equation, so will have:

5x + 2×2 = 9

5x + 4 = 9

5x = 5

x = 1