You want to prepare 10 mL of a 1/100 dilution. What should the aliquot and diluent volumes be? What is the dilution factor when you add 2 mL sample to 8 mL diluent? You diluted a bacterial culture a million fold. You then plated out 0.1 mL of the dilution and after incubation, 45 colonies appeared on the plate. How many bacteria/mL were in the original undiluted culture? A sample was diluted by placing a 0.1 mL aliquot into 0.9 mL of diluent, and 1 mL of this dilution was pour-plated. After incubation, 150 colonies appeared. What is the CFU/mL in the original culture? A pure bacterial culture was diluted by adding a 0.1 mL aliquot to 0.9 mL water. Then, 0.1 mL of this dilution was plated out, yielding 82 colonies. Calculate the CFU mL in the original culture.