Final answer:
The number of bacteria is 1000 times greater than the number of phytoplankton.
Step-by-step explanation:
To find how many times greater the number of bacteria is compared to the number of phytoplankton, we need to divide the number of bacteria by the number of phytoplankton.
The scientist found that there were 1 x 10^9 bacteria and 1 x 10^6 phytoplankton. Dividing the number of bacteria by the number of phytoplankton gives us:
1 x 10^9 / 1 x 10^6 = 1000 times
Therefore, the number of bacteria is 1000 times greater than the number of phytoplankton.