If x is greater than or equal to 25 and y is less than or equal to 40, then which one of the following is always correct?

Correct Option: (y - x) is less than or equal to 15

We are given that x is greater than or equal to 25 (x >= 25) and y is less than or equal to 40 (y <= 40). We want to find which option is always correct. Let's analyze y - x: Since y <= 40 and x >= 25, the maximum value of y is 40 and minimum value of x is 25. Therefore, the maximum possible value of (y - x) is 40 - 25 = 15. If x is greater than 25 (e.g., 30) and y is less than 40 (e.g., 35), (y - x) = 5, which is also less than or equal to 15. In all possible cases, (y - x) is always less than or equal to 15. Checking other options: x is not always greater than y (e.g., x=25, y=30); (x + y) is not always >= 65 (e.g., x=25, y=30 gives 55). Thus, option 3 is always correct.