a) If you need to do a 1:20 dilution on a culture to get acceptable plate counts, how many microliters of original sample will you add to a final volume of 4 mL?

• For this course, a 1:20 dilution is 1 part culture to a final volume of 20 parts.
  • For example, 1 mL culture and 19 mL sterile DI water.
• Report your answer in standard notation rounded to 2 decimal place
• Include trailing zeros if necessary so your answer has 2 decimal places

b) If you need to do a 1:20 dilution on a culture to get acceptable plate counts, how many milliliters of original sample will you add to a final volume of 16 mL? Report your answer in standard decimal notation rounded to two decimal places.

• For this course, a 1:20 dilution is 1 part culture to a final volume of 20 parts.
  • For example, 1 mL culture and 19 mL sterile DI water.
• Report your answer in standard notation rounded to 2 decimal place
• Include trailing zeros if necessary so your answer has 2 decimal places