1. The problem is to understand why we multiply 0.8 by 3. 2. Multiplication is a way to add a number to itself a certain number of times. For example, multiplying 0.8 by 3 means adding 0.8 three times. 3. The formula for multiplication is: $$a \times b = a + a + \cdots + a \text{ (b times)}$$ 4. So, multiplying 0.8 by 3 means: $$0.8 \times 3 = 0.8 + 0.8 + 0.8$$ 5. Adding these together: $$0.8 + 0.8 + 0.8 = 2.4$$ 6. Therefore, multiplying 0.8 by 3 gives 2.4 because you are adding 0.8 three times. This is why we multiply 0.8 by 3.