Final Cover - For Printing

3. Conversion from denary to octal
   A denary number can be converted into an octal number by dividing the given number
   by 8 continuously until the final remainder is either equal to 0 or a value less than 8,
   and the remainders in each step form the octal equivalent of the given denary number.
   The idea can be taught with an example with the assistance of necessary Braille text
   material. The child needs to be given adequate practice in performing the sums on
   his/her own.

Eg. : Convert 123 into an octal number

(^) ∴ 123 = 173 8

4. Binary addition
   The following rule is to be followed in adding two or more binary numbers.

0 + 0 = 0

0 + 1 =1

1 + 0 =1

1 + 1 =10

10 + 1 = 11

11 + 1 = 100

100 + 1 = 101

101 + 1 = 110

110 + 1 = 111

111 + 1 = 1000

Eg. : Add : 1101 + 1111

8 123

8 15 - 3

1 - 7

This is a simple logic. When the numbers are

added, the added value should be the next

number involving 0 or 1. For example, in 10+1,

the immediate next number is 11. In 11+1, the

next available number involving 0 or 1 is 100.

The child may be helped to understand this logic

through repeated exercies.

1101

1111

11100

+

In binary operation two numbers should be added

at a time. In this addition, the operation should

start from right to left. 1 + 1 = 10, and therefore

put 0 as the added value and carry over 1 to the

column in the immediate left. Now 1 + 0 = 1, and

1 + 1 = 10, put 0 in the result column and the

1 should be carried over to the immediate left

column and so on.