If a double stranded DNA has 20 per cent of cytosine, calculate the per cent of adenine in the DNA.

Explanation

To solve the problem of calculating the percentage of adenine in a double-stranded DNA that has 20% cytosine, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Chargaff's Rule**: According to Chargaff's rule, in a double-stranded DNA:
- The amount of adenine (A) is equal to the amount of thymine (T).
- The amount of cytosine (C) is equal to the amount of guanine (G).

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