The weight of an empty gas cylinder is 18 kg 75 g. The weight of the gas contained in it is 12 kg 350 g. What is the total weight of the cylinder filled with gas?

Answer

To find the total weight of the gas cylinder filled with gas, we need to add the weight of the empty gas cylinder to the weight of the gas contained in it. Let's break this down step by step.

### Step 1: Convert the weight of the empty gas cylinder to kilograms
The weight of the empty gas cylinder is given as 18 kg 75 g.
- We know that 1 kg = 1000 g, so we need to convert 75 g to kilograms.
- \( 75 \, \text{g} = \frac{75}{1000} \, \text{kg} = 0.075 \, \text{kg} \)

Now, we can express the total weight of the empty gas cylinder in kilograms:
- \( 18 \, \text{kg} + 0.075 \, \text{kg} = 18.075 \, \text{kg} \)

### Step 2: Convert the weight of the gas to kilograms
The weight of the gas is given as 12 kg 350 g.
- Again, we convert 350 g to kilograms.
- \( 350 \, \text{g} = \frac{350}{1000} \, \text{kg} = 0.350 \, \text{kg} \)

Now, we can express the total weight of the gas in kilograms:
- \( 12 \, \text{kg} + 0.350 \, \text{kg} = 12.350 \, \text{kg} \)

### Step 3: Add the weights together
Now we have both weights in kilograms:
- Weight of the empty gas cylinder: \( 18.075 \, \text{kg} \)
- Weight of the gas: \( 12.350 \, \text{kg} \)

Now, we add these two weights together:
- \( 18.075 \, \text{kg} + 12.350 \, \text{kg} = 30.425 \, \text{kg} \)

### Final Answer
The total weight of the cylinder filled with gas is **30.425 kg**.

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