1. **State the problem:** We need to find the ratio of software engineers proficient in Python to those proficient in Java from a sample of 200 engineers. 2. **Identify given data:** - Proficient in both Python and Java: 50 - Proficient in Python only: 70 - Proficient in Java only: 60 - Proficient in neither language: 20 3. **Calculate total proficient in Python:** Python proficient = Python only + Both $$70 + 50 = 120$$ 4. **Calculate total proficient in Java:** Java proficient = Java only + Both $$60 + 50 = 110$$ 5. **Find the ratio of Python proficient to Java proficient:** $$\text{Ratio} = \frac{120}{110} = \frac{12}{11}$$ 6. **Final answer:** The ratio of those proficient in Python to those proficient in Java is **12:11**.