Under favorable conditions, bacteria can multiply every 20 minutes. starting with one bacteria cell, how many bacteria should you expect after 15 hours? hint: under favorable conditions, if one bacterium becomes 2 in 20 minutes (1 multiplied by 2), those 2 become 4 in the next 20 minutes, and then those 4 become 8 in the next 20 minutes. that means that 8 bacteria resulted in 1 hour. now calculate the growth of bacteria for 15 hours.