Let's calculate the expression step-by-step:

$-12.4 + 19.1 + (-4.3)$

1. Combine the first two numbers:

$-12.4 + 19.1 = 6.7$

2. Now add $-4.3$:

$6.7 + (-4.3) = 6.7 - 4.3 = 2.4$

So, the result is:

$2.4$

Would you like more details or have any questions? Here are some related questions:

1. How would you handle the addition of more negative and positive numbers?
2. How can you use a number line to visualize this calculation?
3. What is the rule for adding and subtracting negative numbers?
4. How can you apply this to solving real-world problems?
5. How would this change if you multiplied instead of added?

Tip: When adding or subtracting numbers, think of positive numbers as gains and negative numbers as losses.