Final answer:
The population of bacteria will double twice over the span of 30 minutes, resulting in a total of 400,000 bacteria.
Step-by-step explanation:
Based on the fact that the population of bacteria doubles every 15 minutes, this falls under the concept of exponential growth. At 15 minutes, the population, starting with 100,000 bacteria, doubles to 200,000. Then in 30 minutes, the newly doubled population of 200,000 will double again to become 400,000. Therefore, if the number of bacteria in a colony doubles every 15 minutes and you have a current population of 100,000 bacteria, the population 30 minutes from now will be 400,000.
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