Looks like the PMF is supposed to be

which is kinda weird, but it's not entirely clear what you meant...
Anyway, assuming the PMF above, for this to be a valid PMF, we need the probabilities of all events to sum to 1:

Next,





If

, then

, where we take the positive root because we know

can only take on positive values, namely 1, 2, and 5. Correspondingly, we know that

can take on the values

,

, and

. At these values of

, we would have the same probability as we did for the respective value of

. That is,

Part (5) is incomplete, so I'll stop here.
Answer:
y = 24
angle V = 67
as a 4 sided shape, the angles all have to add up to 360 degrees.
we already have the answers for R, 120, and B, 53. We have 187 degrees left to work with.
Based of the information the tics on the sides of the figure gives us, we know that angle P and R are the same! First (just for fun, this isn't needed) we'll find X.
(x+95) = 120
-95 -95
x = 25
We know 3/4 angles now, so by subtracting their sum from 360, we'll find angle V!
360 - 53 -120 - 120 = 67
Angle V is 67
Now to find y!
(2y+19)=67
-19 -19
2y = 48
/2 /2
y = 24
Try C, i am not completely sure but i tried
Answer: 50%
There are 2 sides, one of which is tails, so
P(tail) = 1/2 = 0.50 = 50%
I did (450*3/4=337.5) to get how much each person would eat, then I did (337.5*14=4725g) to see how big the turkey should be. I then converted grams to kilos (4725*0.001=4.725 kg), and I got how big the turkey would be. It turns out the appropriate size of the turkey would be medium, so then what I did was that I looked for the medium price of the turkey per kg, and found that it was £5.99 per kg. I did (4.725*5.99) and I got about £28.30.
It would cost £28.30 for 14 people.