To multiply the fractions $-\frac{3}{5}$ and 3, follow these steps:

1. Convert 3 into a fraction: $3 = \frac{3}{1}$.
2. Multiply the two fractions: $\left( -\frac{3}{5} \right) \times \frac{3}{1} = \frac{-3 \times 3}{5 \times 1} = \frac{-9}{5}.$

Thus, the product is $-\frac{9}{5}$.

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Here are 5 related questions you might find useful:

1. How do you multiply two fractions with negative signs?
2. What if both numbers were positive, how would that change the product?
3. How can you simplify a fraction when the numerator and denominator share a common factor?
4. How do you divide fractions instead of multiplying them?
5. What happens if you multiply a fraction by a whole number?

Tip: When multiplying fractions, simply multiply the numerators together and the denominators together.