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Floating Point Binary

Floating Point Binary: Definition

Current size definition

Normalised floating point binary representation with a mantissa and exponent both in two's complement binary

Mantissa:6
Exponent:4

Valid range for positive values:
Binary:0.000000001 to 1111100
Denery:0.001953125 to 124

Valid range for negative values:
Binary:-0.000000001 to -10000000
Denery:-0.001953125 to -128

Change the size of the mantissa and exponent

Select the size of the mantissa

Select the size of the exponent


The following is the floating point representation of a number

MantissaExponent
0●000101100

The value is not normalised. What is the normalised form of this binary number?

Mantissa

           

Exponent

               

Clue

Mantissa: 000010

  • To calculate the new mantissa: shift the digits of the mantissa to the left until the first two characters are 01

Exponent: 1100 = -4

  • Offset = The number of places that the Mantissa is shifted to the left
  • To calculate the new exponent: subtract the offset from exponent value
MantissaExponent
0●000101100
Not Normalised

Mantissa Calculation

Original Mantissa: 000010

Normalised Mantissa: 010000

The digits are shifted to the left by 3

offset = 3


Exponent Calculation

Original Exponent: 1100 = -4

Subtracting the offset from the exponent value: -7

Normalised Exponent: 1001


Denary Value

Value: 0.00390625

MantissaExponent
0●100001001
Normalised

What is the Normalised Floating Point representation of the denary value 3.625

Mantissa

           

Exponent

               

Clue

Fixed Point Binary Value = 11.101

Answer

Denary = 3.625

Fixed Point Binary Value = 11.101

Mantissa = 011101

Exponent Value = 2

Exponent = 0010

MantissaExponent
0●111010010

The following is the binary floating point representation of a number

MantissaExponent
1●001100010

Calculate the denary equivalent of the number

Clue

Standard Form = -0.11010 x 22

MantissaExponent
-1
1
2
1
4
1
8
1
16
1
32
-8421
1●001100010

Answer

Exponent = 0010

Exponent Value = 2

Mantissa = 100110 (Two's Complement)

Mantissa = -011010 (Signed Value)

Standard Form = -0.11010 x 22

Fixed Point Binary Value = -11.01

Denary Value = -3.25

MantissaExponent
-1
1
2
1
4
1
8
1
16
1
32
-8421
1●001100010

The following is an approximate binary floating point representation of the number 0.35

MantissaExponent
0●101101111

Calculate the denary equivalent of the binary number

Clue

Standard Form = 0.10110 x 2-1

MantissaExponent
-1
1
2
1
4
1
8
1
16
1
32
-8421
0●101101111

Answer: Denary Equivalent

Exponent = 1111

Exponent Value = -1

Mantissa = 010110 (Two's Complement)

Standard Form = 0.10110 x 2-1

Fixed Point Binary Value = 0.01011

Denary = 0.34375

MantissaExponent
-1
1
2
1
4
1
8
1
16
1
32
-8421
0●101101111

Contents Copyright 2026 Andy Abraham

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