Daily Math Puzzle: 2026-05-12

Send the difference in fuel levels between Tank A and Tank B — Sending the difference between the fuel in Tank A and Tank B is enough to pin down the whole situation. There are only three possible assignments of "full", "half‑full" and "empty" to the three tanks, because each capacity is distinct: 1. A = full (1000 L), B = half (1000 L), C = empty (0 L) → difference A‑B = 0 L 2. A = full (1000 L), B = empty (0 L), C = half (1500 L) → difference A‑B = 1000 L 3. A = half (500 L), B = full (2000 L), C = empty (0 L) → difference A‑B = -1500 L 4. A = half (500 L), B = empty (0 L), C = full (3000 L) → difference A‑B = 500 L 5. A = empty (0 L), B = full (2000 L), C = half (1500 L) → difference A‑B = -2000 L 6. A = empty (0 L), B = half (1000 L), C = full (3000 L) → difference A‑B = -1000 L Each possible difference value (0, 1000, ‑1500, 500, ‑2000, ‑1000) occurs only once among the six arrangements, so Mission Control can look at the reported difference and instantly know which tank is full, half‑full, and empty. The other three answer choices do not give a unique mapping: the total fuel could correspond to several arrangements, the amount in Tank A alone leaves ambiguity, and knowing the level of the largest tank (C) still leaves two possibilities for A and B. Hence the correct choice is the third one.