The population of bacteria in a petri dish doubles every 12 h. The population of the bacteria is initially 500 organisms.

Question

How long will it take for the population of the bacteria to reach 800?

Round your answer to the nearest tenth of an hour.

Answer 1

500 (2^(t/12)) = 800 , where t is in hours
2^(t/12) = 1.6
take logs of both sides, and use the rules of logs
t/12 log2 = log 1.6
t/12 = log 1.6/log 2
t = 12(log 1.6/log 2)
= appr 8.1 hours

Answer 2

t=8.136864
-nutz