from fractions import Fraction
solutions = []
for low_kg in range(21):
    high_kg = 20 - low_kg
    salt = Fraction(low_kg, 10) + Fraction(3 * high_kg, 10)
    if salt == Fraction(18, 100) * 20:
        solutions.append((low_kg, high_kg, salt))
assert len(solutions) == 1
x, y, salt = solutions[0]
result = {"low_kg": str(x), "high_kg": str(y), "final_salt_fraction": str(salt / 18)}
import json
print(json.dumps(result, ensure_ascii=False, sort_keys=True))