Take your original equation 
and multiply both sides by
to remove the fractions. You are left with

So, 
Update: There is no numerical answer that can be found without being given a value for either x or y

Explanation:
Since we have given that
The prices of three t-shirts styles i.e $24, $30, $36 with their probability is given by

As we know that,


Now,

and

So,

So, the expected value of a t-shirt = $31.
I believe the answer is, 2) End of Reconstruction
The function of the length z in meters of the side parallel to the wall is A(z) = z/2(210 - z)
<h3>How to write a function of the length z in meters of the side parallel to the wall?</h3>
The given parameters are:
Perimeter = 210 meters
Let the length parallel to the wall be represented as z and the width be x
So, the perimeter of the fence is
P = 2x + z
This gives
210 = 2x + z
Make x the subject
x = 1/2(210 - z)
The area of the wall is calculated as
A = xz
So, we have
A = 1/2(210 - z) * z
This gives
A = z/2(210 - z)
Rewrite as
A(z) = z/2(210 - z)
Hence, the function of the length z in meters of the side parallel to the wall is A(z) = z/2(210 - z)
Read more about functions at
brainly.com/question/1415456
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