When the positive integer A is divided by 9 and 7, the…

When the positive integer A is divided by 9 and 7, the remainder is 3 and 4, respectively. When the positive integer B is divided by 9 and 7, the remainder is 3 and 4, respectively. Which of the following must be a factor of A-B?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #80269