What is an advantage of performing a series of dilutions vs. a simple dilution?

The series dilution method is the step wise dilution technique where the dilution factors remain constant in each step.  

The advantages of using the series of dilution method over simple dilution are stated below:

a)        Aids in reduction of a dense culture of cells to a more usable concentration.

b)        In every step of dilution the specific amount of bacteria is removed.

c)        Helps in the estimation of concentration of an unknown sample.

This sums up the advantage of using the series dilution technique.

the index of refraction of the second medium is higher. i just took the test trust me !

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