Question

anticipating exponential growth
at 10:05 a.m., there are 2 microscopic bacteria cells in the bottle. how many cells will be in the bottle at 10:15 a.m.?
2
4
8
16

Explanation:

Step1: Determine time - interval

The time from 10:05 a.m. to 10:15 a.m. is 10 minutes. Assume bacteria double every 5 minutes.

Step2: Calculate number of doubling - periods

In 10 minutes, the number of 5 - minute periods is $\frac{10}{5}=2$.

Step3: Use exponential growth formula

The initial number of bacteria $a = 2$, and the number of doubling - periods $n = 2$. The formula for exponential growth of bacteria (doubling) is $y=a\times2^{n}$. Substitute $a = 2$ and $n = 2$ into the formula: $y = 2\times2^{2}=2\times4 = 8$.

Answer:

C. 8