10 mL of a liquid A were mixed with 10 mL of liquid B. The volume of resulting solution was found to be 19.9 mL. What do you conclude?

Explanation

To solve the problem, we need to analyze the mixing of two liquids, A and B, and the resulting volume of the solution.

### Step-by-Step Solution:

1. **Identify the Initial Volumes**:
- We have 10 mL of liquid A and 10 mL of liquid B.
- Therefore, the total initial volume before mixing = Volume of A + Volume of B = 10 mL + 10 mL = 20 mL.

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