How many microliters to add to meet dilution factor criteria for samples?

Question

I am looking for an equation.

I have a sample with a dilution factor of 0.8, and another with a dilution factor of 0.6. I need to create a vial of each, with various dilution factors. Each will use 5mL of water to dilute the sample.

Of each sample, I will need vials with dilution factors of 250, 500, and 10,000.

How many microliters of the samples will go in each vial?

Answer 1

Short answer: 5000 microliters / ((250, 500, or 10000)*(0.8, or 0.6) = microliters required.

If diluting by a factor of 250, you have 1/250 ratio

The total amount is 5000 microliters the added amount from the sample should be negligible.

So you can set the ratios equal to each other and solve for x: (x*0.8)/5000 = 1/250 and you just change the numbers for which sample used and what you want to dilute to.