calculate the amount of undiluted culture x ml you will add

calculate the amount of undiluted culture \"x ml\" you will add to 40 ml broth to get OD600=0.1?

NOTE:Initial OD600 for diluted culture=0.775

the dilution made is 1:10 dilution.

Solution

40 ml broth OD 600 needed = 0.1

Initial OD = 0.775 and the dilution is 1:10

By diluting in 1:10 the original sample will get 10 times low OD than the original without diluting. So, the original sample has the OD 0.775 x 10 = 7.75

Now we need 0.1 OD, so

O₁ V₁ = O₂ V₂ formula is use here, where O is using for Optical density and V for volume.

O₁ = 7.75, V₁ = ‘X’ ml, O₂ = 0.1, and V₂ = 40 ml

7.75 x X = 0.1 x 40

X = 4/7.75 =0.516 0.52 ml