Chapter 1 - First-Order Differential Equations - 1.5 Some Simple Population Models - Problems - Page 51: 1

Thus, the number of bacteria that were present after 24 hours are $2560$

Given that: $P(t)=P_0e^{(kt)}$ Doubling the time: $t_d=\frac{1}{k} \ln 2$ We know that the bacteria double in 3 hours: $k=\frac{1}{3} \ln 2$ $P_0=10$ and time $t=24$ So, $P(t)=10e^{(\frac{1}{3} \ln 2\times 24)}$ $P(t)=2560$ Thus, the number of bacteria that were present after 24 hours are $2560$.