Addition of 2's Complement Numbers

(a) Positive numbers, sum < 2^(n-1)

+3 0011

+4 0100

+7 0111 (correct answer)

(b) Positive numbers, sum >= 2^(n-1)

+5 0101

+6 0110

1001 (wrong since overflow)

(c) Pos + Neg numbers, Neg > Pos

+5 0101

-6 1010

-1 1111

(d) Pos + Neg numbers, Pos > Neg

-5 1011

+6 0110

+1 0001 (correct if carry ignored)

(e) Negative no's. |sum| <= 2^(n-1)

-3 1101

-4 1100

-7 1001 (correct if carry ignored)

(f) Negative no's. |sum| > 2^(n-1)

-5 1011

-6 1010

0101 (wrong since overflow)

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