If the father's age is 3 years more than thrice the son's age and after 5 years from now, the father's age will be 12 years more than twice the son's age, then the present age of the father is.

Let the present age of the son be x years and the present age of the father be y years.

According to the given conditions:
1. y = 3x + 3
2. y + 5 = 2(x + 5) + 12

Substitute the value of y from equation 1 into equation 2:
3x + 3 + 5 = 2(x + 5) + 12
3x + 8 = 2x + 10 + 12
3x + 8 = 2x + 22
3x - 2x = 22 - 8
x = 14

Substitute the value of x back into equation 1:
y = 3(14) + 3
y = 42 + 3
y = 45

Therefore, the present age of the father is 45 years.

Let the present age of the father be F and the present age of the son be S.
Given that F = 3S + 3 ---------------- (i)
After 5 years, the father's age will be F + 5 and the son's age will be S + 5.
Also given that F + 5 = 2(S + 5) + 12 -------- (ii)
Substituting the value of F from equation (i) in equation (ii), we get
3S + 3 + 5 = 2(S + 5) + 12
⇒ 3S + 8 = 2S + 10 + 12
⇒ 3S - 2S = 10 + 12 - 8
⇒ S = 14
Substituting the value of S = 14 in equation (i), we get
F = 3(14) + 3
⇒ F = 42 + 3
⇒ F = 45
Therefore, the present age of the father is 45 years.