Add the following binary numbers and check your result by decimal addition.
$\begin{array} { c}
1111111\
111111 \
\hline
\end{array}$
A) 10010111
B) 1101101
C) 1101011
D) 10111110
E) 10100001

Question

Add the following binary numbers and check your result by decimal addition. 
$\begin{array} { c} 
1111111\
111111 \
\hline
\end{array}$
A) 10010111
B) 1101101
C) 1101011
D) 10111110
E) 10100001

Quizplus · Accepted Answer

Adding the two binary numbers, we get: 
$$\begin{array} { c@{}c@{}c@{}c@{}c@{}c@{}c@{}c} 
& & & 1 & 1 & 1 & 1 & 1 & 1_2 \
& & & 1 & 1 & 1 & 1 & 1 & \
\cline{2-9}
& & 1 & 0 & 1 & 1 & 1 & 1 & 0_2 \
\end{array}$$
Converting this binary number to decimal, we get 223. 
Similarly, converting the given options to decimal, we get: 
A) 151 
B) 109 
C) 107 
D) 223 
E) 161

Hence, the best choice is D as it matches with the decimal addition check.

Add the Following Binary Numbers and Check Your Result by Decimal