#### Answer

$111111$

#### Work Step by Step

Align the addends at the decimal point and sum the digits with the same place value.
In binary notation, the allowable digits are 0 and 1. In standard Base 10 notation, when the sum of one of the columns is 10 or greater, you write the ones digit as the sum for that column and carry the tens digit to the next column. In binary (or Base 2) addition, the same process is used when the sum of one of the columns is 2 or greater.
In binary notation, 1+1+1=11, so you would write 1 as the sum for the column and carry the 1 to the next column.
$\ \ \ \ \ \overset{1}1\,\overset{1}1\,\overset{1}0\,1\,1$
$\ \ \ \ \,1\,0\,1\,1\,0$
$\underline{\ \ \ \ \ \ \ \ 1\,1\,1\,0}$
$\ \ 1\,1\ 1\,1\ 1\ 1$