From what I gather from your latest comments, the PDF is given to be
and in particular, <em>f(x, y)</em> = <em>cxy</em> over the unit square [0, 1]², meaning for 0 ≤ <em>x</em> ≤ 1 and 0 ≤ <em>y</em> ≤ 1. (As opposed to the unbounded domain, <em>x</em> ≤ 0 *and* <em>y</em> ≤ 1.)
(a) Find <em>c</em> such that <em>f</em> is a proper density function. This would require
(b) Get the marginal density of <em>X</em> by integrating the joint density with respect to <em>y</em> :
(c) Get the marginal density of <em>Y</em> by integrating with respect to <em>x</em> instead:
(d) The conditional distribution of <em>X</em> given <em>Y</em> can obtained by dividing the joint density by the marginal density of <em>Y</em> (which follows directly from the definition of conditional probability):
(e) From the definition of expectation:
(f) Note that the density of <em>X</em> | <em>Y</em> in part (d) identical to the marginal density of <em>X</em> found in (b), so yes, <em>X</em> and <em>Y</em> are indeed independent.
The result in (e) agrees with this conclusion, since E[<em>XY</em>] = E[<em>X</em>] E[<em>Y</em>] (but keep in mind that this is a property of independent random variables; equality alone does not imply independence.)
Answer:
The problem basically is saying that find two numbers that add up to 8, where one is three times the other.
Step-by-step explanation:
The best thing to do here is to write a simple system of equations.
b+y=8
b=3y
The first equation means that the total blue paint plus the total yellow paint is equal to 8 ounces.
The second equation means that the blue paint is equal to 3 times the yellow paint.
We can isolate b in the first equation to get b=-y+8
-y+8=3y
8=4y
y=2.
So we have that she needs two ounces of yellow paint.
Therefore she needs six ounces of blue paint.
Drag the yellow bar to 2, and the blue bar to 6.
Hope this helps!
-1/5, -2/3, .04, 2
Hope this helps :)
A. Lotta boonk gangs in a whole.
Real life problem for quadratic equation:
A ball is thrown into the air from the edge of a building, 50 feet above ground. It’s initial velocity is 20 feet per second. About how long does it take for the ball to hit the ground?
Sorry if this doesn’t help.