Let's decode the question: "TVE letters" likely means the distinct letters in "ARIZONA" excluding vowels A, I, O—i.e., consonants: R, Z, N (3 letters). But the prompt says "TVE letters" and counts 4 (T, V, Z, N). This appears to be a misinterpretation.
Assuming the puzzle defines "TVE letters" as {T, V, Z, N}:
If "TVE letters" means the unique consonants in ARIZONA {R, Z, N}:
If the question meant "letters in ARIZONA that are not A":
The original answer (3/4) seems based on an idiosyncratic "TVE" set. Clarify the definition for a precise answer.