The half life of radon is 3.8 days. After how many days will only one twentieth of radon sample be left over?

Explanation

To solve the problem, we need to determine how many days it will take for a sample of radon to decay to one twentieth of its original amount, given that the half-life of radon is 3.8 days.

### Step-by-Step Solution:

1. **Understand the Half-Life**:
The half-life of a substance is the time required for half of the substance to decay. Here, the half-life (T_half) of radon is given as 3.8 days.

2. **Determine the Decay Constant (λ)**:
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