Final answer:
The sum of two numbers depends on their signs. For addition, if the signs are the same, add the numbers and keep the sign. If the signs are different, subtract the smaller number from the larger number and use the sign of the larger number.
Step-by-step explanation:
The answer to the question a. 4.6 + (–5.9) is -1.3. When adding a positive number (4.6) and a negative number (-5.9), the rule is to subtract the smaller number from the larger number and use the sign of the larger number. In this case, subtracting 5.9 from 4.6 gives us -1.3.
The answer to the question b. –4.4 + 6.2 is 1.8. Adding a negative number (-4.4) and a positive number (6.2) results in a positive number. This follows the rule that when two numbers with opposite signs add, the answer has the sign of the larger number.
The answer to the question c. 2.1 + 0.5 is 2.6. Both numbers are positive, so the sum is also positive.
The answer to the question d. –3.8 + (–1.3) is -5.1. Adding two negative numbers results in a negative number, following the rule that when two negative numbers add, the answer has a negative sign.