3 years ago, the sum of the ages of the mother and son was 49, and this year, when the mother is 4 times the age of the son, how old is the son this year?
49 3 2 [OP_MUL] [OP_ADD] 1 4 [OP_ADD] [OP_DIV]
var_a = 49
var_b = 3
var_c = 2
var_d = var_b * var_c
var_e = var_a + var_d
var_f = 1
var_g = 4
var_h = var_f + var_g
var_i = var_e / var_h
print(int(var_i))