Factorise; c cubed divided by c cubed?<br> HELP ASAP

You work at a job where your average monthly earnings are $682 with a standard deviation of $49. Your mean monthly expenses are

Pavel [41]

Answer:

S = I-E.

We can find the expected value of S and we got:

$E(S) = E(I-E) = E(I) -E(E)= 682-211=471$

And that represent the mean of the amount of money into your savings account each month

And now we can find the variance of the random variable S like this:

$Var(S) = Var(I-E) = Var(I) +Var(E) - 2Cov(I,E)$

And since we know that $Cov (I,E) =0$ then we have:

$Var(S) = Var(I) + Var(E) = 49^2 + 16^2 = 2657$

And then the deviation would be:

$Sd(S) = \sqrt{2657}= 51.546$

And that represent the standard deviation of the amount of money you put in your savings account each month

Step-by-step explanation:

Let I the random variable that represent the income for each month and we know:

$E(I) = 682, \sigma_I = 49$

Let E the random variable that represent the monthly expenses for each month and we know:

$E(E)= 211, \sigma_E = 16$

And for this case we know that the random variables I and E are independent, so then $Cov(I, E) = 0$

We can define the random variable S representing the amount that we can save each month and we can define S = I-E.

We can find the expected value of S and we got:

$E(S) = E(I-E) = E(I) -E(E)= 682-211=471$

And that represent the mean of the amount of money into your savings account each month

And now we can find the variance of the random variable S like this:

$Var(S) = Var(I-E) = Var(I) +Var(E) - 2Cov(I,E)$

And since we know that $Cov (I,E) =0$ then we have:

$Var(S) = Var(I) + Var(E) = 49^2 + 16^2 = 2657$

And then the deviation would be:

$Sd(S) = \sqrt{2657}= 51.546$

And that represent the standard deviation of the amount of money you put in your savings account each month

3 0

3 years ago

What is the equation of this line?

postnew [5]

$y = \frac{1}{2} x - 2$

6 0

2 years ago

Read 2 more answers

What is the perimeter of the quadrilateral ABCD?

lara31 [8.8K]

Answer:

triangle abd is isosceles triangle and triangle dbc is equilateral triangle.

opposite sides of equal angles are same. so, ad= bd

and bd is the side of equilateral triangle. so, bd=bc=dc

perimeter of quadrilateral = sum of all sides.

perimeter=11+8+8+8

perimeter =35

3 0

2 years ago

This is kinda urgent, pls answer with work shown ;-;

igomit [66]

Answer:

the answer is 13. 6 is the correct answer

8 0

2 years ago

Which of these numbers are irrational?<br>see in picture for answer choices

Likurg_2 [28]

Option A:

$\sqrt{17}, \sqrt[3]{14}$ are irrational numbers.

Solution:

Given numbers:

$$\sqrt{17} , 0, \sqrt[3]{8} , \frac{22}{7} , \sqrt{81} , \sqrt[3]{14}$

To which of these are irrational numbers:

<u>Irrational:</u>

An irrational number cannot be written in the form $\frac{a}{b}$ , where a and b are integers and b is non-zero.

(1) $\sqrt{17}$ cannot be written as $\frac{a}{b}$ .

So, it is a irrational.

(2) $\sqrt[3]{8} =\sqrt[3]{2^3}$

Cube and cube roots are get canceled.

$\sqrt[3]{8} =2$

2 is an integer. So it is not a irrational number.

(3) $\frac{22}{7}$ is in the form $\frac{a}{b}$ .

So it is not a irrational number.

(4) $\sqrt{81}=\sqrt{9^2}$

Square and square root are get canceled.

$\sqrt{81}=9$

9 is an integer. So it is not a irrational number.

(5) $\sqrt[3]{14}$

14 cannot be written as $\frac{a}{b}$ form.

So, it is a irrational number.

Therefore $\sqrt{17}, \sqrt[3]{14}$ are irrational numbers.

Option A is the correct answer.

6 0

3 years ago

Factorise; c cubed divided by c cubed? HELP ASAP