The pressure in a helium gas cylinder is initially 30 atmospheres. After many balloons have been blown up, the pressure has decreased to 6 atm. What fraction of the original gas remains in the cylinder ?

Explanation

To find the fraction of the original gas that remains in the helium gas cylinder after the pressure has decreased, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Initial and Final Pressures**:
- Initial pressure \( P_i = 30 \, \text{atm} \)
- Final pressure \( P_f = 6 \, \text{atm} \)

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