By how much is difference of `18.89` and `11.21` less than that of their sum ?

Explanation

To solve the problem of finding out by how much the difference between `18.89` and `11.21` is less than their sum, we can follow these steps:

### Step 1: Calculate the Difference
We need to find the difference between `18.89` and `11.21`.

\[ \text{Difference} = 18.89 - 11.21 \]
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