If 250ml of `N_(2)` at `30^(@)C` and a pressure of 250mm Hg are mixed with 400ml of `CH_(4)` at `30^(@)C` and pressure of 300mm Hg so that the volume of the resulting mixture is 350ml, what will be the final pressure of the mixture at `30^(@)C`? 

Explanation

To solve the problem of finding the final pressure of the gas mixture, we can use the principles of gas laws, specifically Boyle's Law, which states that for a given mass of gas at constant temperature, the product of pressure and volume is a constant.

### Step-by-Step Solution:

1. **Identify the Given Values:**
- For Nitrogen (N₂):
- Volume (V₁) = 250 ml
- Pressure (P₁) = 250 mm Hg
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