Simplify: `(-3)/(10)+7/(15)+3/(-20)+(-9)/(10)+(13)/(15)+(13)/(-20)`

Explanation

To simplify the expression \(\frac{-3}{10} + \frac{7}{15} + \frac{3}{-20} + \frac{-9}{10} + \frac{13}{15} + \frac{13}{-20}\), we will follow these steps:

### Step 1: Group the fractions with the same denominators
We can group the fractions based on their denominators:
- For \(\frac{-3}{10}\) and \(\frac{-9}{10}\)
- For \(\frac{7}{15}\) and \(\frac{13}{15}\)
- For \(\frac{3}{-20}\) and \(\frac{13}{-20}\)

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