(adsbygoogle = window.adsbygoogle || []).push({}); binary to decimal confusion!!! signed numbers!

OKay this makes no sense to me...

THe directions say:

The following binary numbers have a sign in the leftmost postion and if negative, are in 2's complement form. Perofrm the indciated airthmeic operations and verify the answers.

So i have:

110001

-010010 = ?

010010 = 18, but since we are subtracting its -18.

1 10001 is in two's compliment form so we have to convert it to its regular magnitude by taking 2's compliment of it.

which is

001110 + 1 = 001111 = 15, but since the sign is a 1 above, its -15;

so we got -15 - 18 = -33

So we know the answer has to be -33; but when u take the 2's compliment of the minuend, u end up with

010010 = 101101 + 1 = 101110;

so now we add that to the top number:

110001

+101110 = 1 011111; we have an overflow of 1, so u delete that and ur left with

011111 = 31!! what the heck is going on!

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# Homework Help: Binary to decimal confusion signed numbers!

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