Study the following information carefully and answer the given question. The information is related and given in sequence: I. Bag X contains a total o...

Study the following information carefully and answer the given question. The information is related and given in sequence:

I. Bag X contains a total of 30 red and green balls. The probability of selecting one red ball and one green ball from the bag is $\frac{40}{87}$. The number of red balls in the bag is denoted as A.

II. B number of green balls are taken out, painted red, and placed back into Bag X.

III. The probability of selecting two green balls from Bag X after this change is $\frac{7}{29}$.

IV. Bag Y contains all balls from Bag X. If C green balls are withdrawn from Bag Y and $(C-5)$ red balls are added, then the probability of selecting two red balls from Bag Y is $\frac{2}{5}$.

Question: Find the probability of selecting $(B-3)$ green balls from Bag X (considering the initial number of red and green balls in the bag).