Canadian Society for Medical Laboratory Science (CSMLS) Practice Exam

What is the dilution when 0.1 mL of a sample is added to 2.9 mL of distilled water?

1. 1:30

2. 1:29

3. 1:29.9

4. 1:3

The correct answer is: 1:29

To determine the dilution when 0.1 mL of a sample is added to 2.9 mL of distilled water, we first need to calculate the total final volume of the solution. The total volume is the sum of the volume of the sample and the volume of the water, which is: 0.1 mL (sample) + 2.9 mL (water) = 3.0 mL (total volume). Next, to find the dilution factor, we compare the volume of the sample (0.1 mL) to the final total volume (3.0 mL). The dilution ratio is determined by the amount of total volume compared to the sample volume: The ratio can be expressed as the number of parts of total solution to the sample volume. In this case, there is 3.0 mL (total) - 0.1 mL (sample) = 2.9 mL of dilution medium. Thus, the dilution can be calculated as follows: Total parts = volume of the sample + volume of the diluent = 0.1 mL + 2.9 mL = 3.0 mL. Now, the volume of the sample is