Answer:
There is no short answer.
Explanation:
In the given example Bobby is creating a solution for his bacteria count which consists of 1% bacterial sample.
Considering that the solution was mixed homogeneously, he can apply the procedure to the remaining sample and get the results he wants.
Or if the average number of bacteria in a 1 mL sample is known, he can apply that information proportionally to the 100 mL mixture and find the original cell concentration.
I hope this answer helps.