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# Computer Science - HELP i cannot understand this!!!

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1. Okay so Floating point binary.
January 2011. q4.
WTF.
Okay so they ask to Represent the number 2.25 with a 5 bit mantissa and 3 bit exponent both in twos complement. Thats calm.. i can do that..

So this is what I write:

01001 110

*checks markschme* apparently.. its wrong.
So the mark scheme says the answer is:

01001 010.
So my exponent was wrong. But in the mark scheme it says "move two places to the left". Correct me if im wrong but moving two places to the left is to have -2 in your exponent right?
Well it could be the mark scheme wrong.
So i open a book.
Q1. Convert 1.625 to normalised floating point 10 bit mantissa and 6 bit exponent

Okay thats cool.. i do it.
Get this: 0110100000 111111
Okay.. so turns out this is wrong too.
My mantissa is right again.. its the exponent
0110100000 000001
Again the issue of moving left? WHAT AM I DOING WRONG!??
2. Ignore me. I'm an idiot. Someone delete this thread immediately.

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