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Output:
To calculate your sister's age, we start with how old she was when you were 6 years old. At that time, she was half your age, so she was 3 years old.
Since the age difference between you and your sister remains constant at 3 years, we can simply add this difference to your current age.
You are now 70 years old, so your sister is now 70 - 3 = 67 years old.
ChatGPT4 has no problems solving the puzzle correctly. Please try it out. Output: