Table of Contents

• Section 1. How to Do a Viable Plate Count
• 1: Why we need to dilute
• 2: Setting the stage: Diluting Cold Press Coffee
• 3: The dilution factor
• 4: Overall dilution
• 5: Design a dilution!
• 6: How to scale back up
• 7: Count a plate!
• 8: Why plate more than one dilution?
• 9: Picking the plate count
• Section 2. Practice Problems
• 10: Putting it all together
• 11: More dilution problems
• 12: Quickies
• 13: Is he dead yet?
• 14: Review

Overall dilution

Now that you are very comfortable with dilution factors... what happens if you dilute and then dilute again? For example, we could take super-strong cofee, dilute it by 1/5, then dilute THAT by 1/10. So,

Here's the rule:

To find the overall (or total) dilution factor,
simply multiply the dilution factors for each step.

Once again, here's an applet to practice finding the total dilution scheme, regardless of how the dilution scheme is expressed -- as directions, as fractions, or as decimals.

Remember, keep going until you're very comfortable with the calculations... Oh, and do yourself a favor, use a calculator!!

Given the following series of dilutions,
what is the total dilution factor?

As a Fraction: 1 /
As a Decimal:
feedback here