Express \((-3)/(5)\) as a rational number with denominator:

here are the answers to the math questions:

1. Express $\frac{-3}{5}$ as a rational number with denominator:

a) Denominator 20:
To change the denominator from 5 to 20, we multiply by 4.

$$\frac{-3}{5} = \frac{-3 \times 4}{5 \times 4} = \boxed{\frac{-12}{20}}$$

b) Denominator -30:
To change the denominator from 5 to -30, we multiply by -6.

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