Answer:
10⁶
Step-by-step explanation:
A 1:100 serial dilution is a dilution in which the concentration decreases 100 fold (i.e., in each dilution the concentration of the culture must be multiplied by 10⁻²). The question above indicates that a three-step 1:100 dilution was applied, which means >> 10⁻² x 10⁻² x 10⁻² = 10⁻⁶. Moreover, the dilution factor can be calculated by dividing the volume of the diluted solution by the volume of the concentrated solution. The dilution factor is the inverse of dilution, thereby in this case this value is equal to 10⁶ (dilution = 10⁻⁶ >> dilution factor = 10⁶).