1. **State the problem:** Solve for $n$ in the equation $0.15 = 0.3n$. 2. **Formula and rules:** To solve for $n$, we need to isolate $n$ by dividing both sides of the equation by the coefficient of $n$, which is $0.3$. 3. **Isolate $n$:** $$ 0.15 = 0.3n $$ Divide both sides by $0.3$: $$ \frac{0.15}{\cancel{0.3}} = \frac{0.3n}{\cancel{0.3}} $$ 4. **Simplify the left side:** $$ \frac{0.15}{0.3} = 0.5 $$ 5. **Final answer:** $$ n = 0.5 $$ So, the solution is $n = 0.5$.