A group of rabbits multiplies at a constant rate

Hi Nez,

Since your question is in regards to a DS prompt, and I understand why you might be interested in the general knowledge behind how the math 'works', it's important to know that the knowledge you're asking for is unnecessary if your goal is to score at a high level on Test Day. The GMAT will NOT ask you to do that math - it's presented here in a DS question to test your conceptual understanding and not your calculation ability.

DS question are often designed with 'shortcuts' built into them, so that a strong critical thinker can get to the correct answer without doing lots of difficult calculations. You have to learn to take advantage of those options and not get hung up on an 'all math, all the time' mindset. You seem to understand that this information is sufficient to answer the question that is asked - when dealing with either Fact in a DS question, once you KNOW (or have proof) that a Fact is sufficient, then you should stop working.

GMAT assassins aren't born, they're made,
Rich