A good answer might be:

In binary:

The Binary Addition Algorithm

The binary addition algorithm is a bit-pattern manipulation procedure that is built into the hardware of (nearly) all computers. All computer scientists and computer engineers know it.

Let us start by adding 1-bit integers. The operation is performed on three operands (three input values). Arrange the bits into a column. The bit at the top of the column is called the "carry into the column".

To add two 1-bit (representations of) integers: Count the number of ones in a column and write the result in binary. The right bit of the result is placed under the column of bits. The left bit is called the "carry out of the column". The following table shows the outcomes with all possible operands.

Binary Addition Table 
                                 the carry into the column 
                                                         |
                                                         | 
  1      1      1      1      0      0      0      0  <--- 
  1      0      1      0      1      0      1      0   
  1      1      0      0      1      1      0      0   
 ---    ---    ---    ---    ---    ---    ---    ---   
 11     10     10     01     10     01     01     00   
                                                  ^
                                                  |
                        the carry out of the column

QUESTION 2:

Perform the following additions: 

 1              0             1
 0              1             1
 1              0             0
---            ---           ---