1. The problem is to divide 0.45 by 0.8. 2. The formula for division is $$\frac{a}{b}$$ where $a$ is the numerator and $b$ is the denominator. 3. To simplify division with decimals, multiply numerator and denominator by the same power of 10 to make the denominator a whole number. 4. Multiply numerator and denominator by 10: $$\frac{0.45 \times 10}{0.8 \times 10} = \frac{4.5}{8}$$. 5. Now divide 4.5 by 8: $$4.5 \div 8 = 0.5625$$. 6. Therefore, the result of $0.45 \div 0.8$ is $0.5625$.