The sum of two rational numbers is `(-3)/5` . If one of the number is `(-9)/(20)` , find the other.

Explanation

To find the other rational number when the sum of two rational numbers is \(-\frac{3}{5}\) and one of the numbers is \(-\frac{9}{20}\), we can follow these steps:

### Step-by-step Solution:

1. **Set Up the Equation**:
Let the other rational number be \(x\). According to the problem, we have:
\[
x + \left(-\frac{9}{20}\right) = -\frac{3}{5}
...