# Math Help - 2's complement binary

1. ## 2's complement binary

Assuming a 8-Bit number system, use the 2's complement method to perform the following arithemetic. Verify your anwsers, showing all workings.

$113_{10}$
- $98_{10}$

$98_{10}$
- $113_{10}$

Exam tomorrow and I need to know how to do this question. Any help would be amazing. Thanks

2. Originally Posted by gary223
Assuming a 8-Bit number system, use the 2's complement method to perform the following arithemetic. Verify your anwsers, showing all workings.

$113_{10}$
- $98_{10}$

...
Hello,

I assume that you know how to convert a number of decimal system in a binary number.
Code:
113   =======>  01110001   [a]
10
98   =======>  01100010   [b]
10

-98   =======>  10011101   [c]
10
+    00000001   [d]
----------------------------
1|00001111   [e]
[a] 113 converted into binary number
[b] 98 converted into binary number
[c] change every digit. The first digit correspond to the sign: 0 means +, 1 means -.