Answer: 3450
Step-by-step explanation: so after 6 hours, 300 new bacteria joined the colony, right? So to know how many bacteria will join after 9 hours, we will need to first know how many bacteria will join after 1 hour. So 6 hours divided by 6 hours is 1 hour. Now 300/6 is 50. So after every 1 hour, 50 bacteria will grow. We want 9 hours, so we multiply 50 by 9 to get an answer of 450 new bacteria. But we can’t forget the bacteria the culture started with, so we add 3000 with 450 is our final answer 3450.