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[Mentor's note: This post does not use the template because it was originally posted in a non-homework forum. I moved it here instead of deleting it and asking the poster to re-post, because he has already shown a reasonable amount of effort.]

I am having a bit of trouble with this homework assignment...

I am given two hexadecimal numbers.

A = 0D34

B = DD17

The directions are to find the sum of A and B if they represent signed 16-bit hexadecimal numbers stored in sign-magnitude format.

I attempted to convert both numbers to binary.

0D34 = 0000 1101 0011 0100

DD17 = 1101 1101 0001 0111

then, because the leading 1 in the binary representation of DD17 makes it negative, I took the 2's comp of DD17 and got 0010 0010 1110 1001.

However when I add that result with the binary representation of 0D34 I get..

0000 1101 0011 0100

+ 0010 0010 1110 1001

--------------------------------

0011 0000 0001 1101

which is represented in hexadecimal as 301D. I know this is wrong because the correct answer is CFE3.

Can anyone point out what I am doing wrong here? It would be of great help.

Thanks.

I am having a bit of trouble with this homework assignment...

I am given two hexadecimal numbers.

A = 0D34

B = DD17

The directions are to find the sum of A and B if they represent signed 16-bit hexadecimal numbers stored in sign-magnitude format.

I attempted to convert both numbers to binary.

0D34 = 0000 1101 0011 0100

DD17 = 1101 1101 0001 0111

then, because the leading 1 in the binary representation of DD17 makes it negative, I took the 2's comp of DD17 and got 0010 0010 1110 1001.

However when I add that result with the binary representation of 0D34 I get..

0000 1101 0011 0100

+ 0010 0010 1110 1001

--------------------------------

0011 0000 0001 1101

which is represented in hexadecimal as 301D. I know this is wrong because the correct answer is CFE3.

Can anyone point out what I am doing wrong here? It would be of great help.

Thanks.

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