Binary adding/subtracting, am i doing this right?

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The discussion revolves around performing binary subtraction using the two's complement method. The user demonstrates subtracting the binary numbers 10110 and 1111, correctly calculating the two's complement of 1111 and arriving at the sum of 10111. They express confusion about the final answer's bit length, questioning whether it should be 4 bits or 5 bits, and conclude that the answer should be 0111. Additionally, they inquire about the subtraction of 101 from 101000, noting discrepancies between their calculations and those from a binary calculator. The user ultimately arrives at a two's complement result of 011101 for this second operation.
mr_coffee
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Hello everyone, I'm alittle confused, we have an exam tomarrow and i want to make sure I'm doing this right. I'm suppose to do the following:
Perform the indicated subtraction with the following unsigned binary numbers by taking the 2's compliment of the subtrahend.
so for one of them:
10110 - 1111
I take the 2's compliment of 1111 which is:
1's compliment: 0000
2's compliment: 0000 + 1 = 0001
now i add 0001 to 10110
10110
+0001
=
10111

now since I'm only adding a 4 bit number to a 5 bit number my final answer will only still be in 4 bits right? so it would be
0111 as the final answer right?
I used a binary calculator and it said the answer is 111, but i think it just wasn't programmed to included the 0 infront.
 
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Also what would
101 - 101000 equal? the calculaotr came out with a huge number:
1111111111111111111111111111111111111111111111111111111111011101when i take the 2's compliment of 101000 and add it to 101 i get: 011101
 

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