Answer:
+ -4.3
Explanation:
To solve for the missing number, we can use this equation:
7.4 - 3.1 = 4.3
Now, we can insert that into the equation:
7.4 + -4.3 = 3.1
But, why is it a negative instead of a positive?
We convert 4.3 into a negative because if it was positive, the number would be getting bigger, not smaller.
Therefore, the calculation completed is 7.4 + -4.3 = 3.1.