Question

Show the decimal integer 79 in 8-bit sign magnitude, one's complement, two's complement and excess-127 respectively in the given order, separated by comma.

Answer 1

Answer:
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01001111,01001111,01001111,11001110

Explanation:
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79
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Since this is a positive number. we can directly convert this into binary
Divide 79 successively by 2 until the quotient is 0
   > 79/2 = 39, remainder is 1
   > 39/2 = 19, remainder is 1
   > 19/2 = 9, remainder is 1
   > 9/2 = 4, remainder is 1
   > 4/2 = 2, remainder is 0
   > 2/2 = 1, remainder is 0
   > 1/2 = 0, remainder is 1
Read remainders from the bottom to top as 1001111
So, 79 of decimal is 1001111 in binary
Adding 1 zero(s) on left hand side of this number to make this of length 8
So, 79 in normal binary format is 01001111
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||    1's complement: 01001111    ||
||    2's complement: 01001111    ||
||    sign-magnitude: 01001111    ||
=====================================

for excess-127:
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for binary value add 127 to 79
127+79 = 206
Divide 206 successively by 2 until the quotient is 0
   > 206/2 = 103, remainder is 0
   > 103/2 = 51, remainder is 1
   > 51/2 = 25, remainder is 1
   > 25/2 = 12, remainder is 1
   > 12/2 = 6, remainder is 0
   > 6/2 = 3, remainder is 0
   > 3/2 = 1, remainder is 1
   > 1/2 = 0, remainder is 1
Read remainders from the bottom to top as 11001110
So, 206 of decimal is 11001110 in binary
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||    excess-127: 11001110    ||
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