We obtain the joint PMF directly from the joint MGF:
Then
Wouldnt it be 0.2 i think
X = k/p^3
125 = k/10^3 = k/1000
1000 x 125 = k
k = 125000
x = 125000/p^3
The profit is given by G = px - (125 + 2x) = p(125000/p^3) - 125 - 2(125000/p^3) = 125000/p^2 - 250000/p^3 - 125
For maximum profit:
dG/dp = 0
dG/dp = -250000/p^3 + 750000/p^4 = 0
750000 - 250000p = 0
p = 750000/250000 = 3
Therefore the price that will yeaild maximum profit is $3.
Answer: Approximately d = 208.72
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Work Shown:
Make sure your calculator is in radian mode
A quick way to check is to compute cos(pi) and you should get -1
cos(angle) = adjacent/hypotenuse
cos(x) = 200/d
cos(0.29) = 200/d
d*cos(0.29) = 200
d = 200/cos(0.29)
d = 208.715135166392 which is approximate
d = 208.72
I rounded to two decimal places since x is rounded in that manner as well. Round however else you need if your teacher instructs.
The pair of numbers that would have 20 as their lcm is 4 and 5