How do you convert Dotted Decimal 121.55.7.15 to Binary?

Answer 1

Each number separated by a dot is an eight bit number, so conversion requires converting four numbers. To convert a decimal number to binary, divide by two in succession until the number zero is reached.

121 / 2 = 60 r 1

60 / 2 = 30 r 0

30 / 2 = 15 r 0

15 / 2 = 7 r 1

7 / 2 = 3 r 1

3 / 2 = 1 r 1

1 / 2 = 0 r 1

Then, you read remainders backwards:

1111001

If there's less than 8 numbers, add zeroes to the left:

01111001

Then, do this for the other numbers.

55 / 2 = 22 r 1

22 / 2 = 11 r 0

11 / 2 = 5 r 1

5 / 2 = 2 r 1

2 / 2 = 1 r 0

1 / 2 = 0 r 1

00101101

7 / 2 = 3 r 1

3 / 2 = 1 r 1

1 / 2 = 0 r 1

00000111

15 / 2 = 7 r 1

7 / 2 = 3 r 1

3 / 2 = 1 r 1

1 / 2 = 1 r 1

00001111

Once you have all the binary digits, simply stick them back together using dots:

01111001.00101101.00000111.00001111