Answer:
the sum is 01011000₂ = 88
Step-by-step explanation:
For numbers of magnitude less than 128, it is convenient to use an 8-bit representation. I find it works will to convert back and forth through the octal (base-8) representation, as each base-8 digit converts nicely to three (3) base-2 bits.
61 = 8·7 +5 = 075₈ = 00 111 101₂
27 = 8·3 +3 = 033₈ = 00 011 011₂
Then ...
[tex]\begin{array}{cc|ccc}&61&&00111101\\+&27&+&00011011\\ &\overline{88}&&\overline{01011000}\end{array}[/tex]
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Starting from the right, we can convert the binary back to octal, then to decimal by considering 3 bits at a time:
01 011 000₂ = 130₈ = 1·8² +3·8 +0 = 64 +24 = 88
The binary sum is the same as the decimal sum.