Add −5.11+(−1.56).

-5.11 + (-1.56) = -6.67

To add −5.11 and (−1.56) together, follow these steps:

Step 1: Start by aligning the decimal points of the two numbers: -5.11 and -1.56.

Step 2: Add the two numbers as you would normally, ignoring the negative signs: 5.11 + 1.56 = 6.67.

Step 3: Since both -5.11 and -1.56 have negative signs, the sum will also be negative.

Therefore, the sum of −5.11 and (−1.56) is −6.67.