`345 mL = "____________"L`

Answer

To convert 345 mL to liters, follow these steps:

### Step 1: Understand the conversion factor
We know that 1 liter (L) is equal to 1000 milliliters (mL). Therefore, to convert milliliters to liters, we can use the conversion factor:
\[ 1 \, \text{L} = 1000 \, \text{mL} \]

### Step 2: Set up the conversion
To convert 345 mL to liters, we can set up the equation:
\[ \text{liters} = \frac{\text{milliliters}}{1000} \]
So, we can write:
\[ \text{liters} = \frac{345 \, \text{mL}}{1000} \]

### Step 3: Perform the division
Now, divide 345 by 1000:
\[ \text{liters} = 345 \div 1000 \]

### Step 4: Place the decimal point
When dividing by 1000, we move the decimal point three places to the left. The number 345 can be written as 345.0. Moving the decimal point three places to the left gives us:
\[ 0.345 \]

### Final Answer
Thus, 345 mL is equal to:
\[ \text{liters} = 0.345 \, \text{L} \]

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