Consider the following floating point format Mantissa is a pure fraction in…
2005
Consider the following floating point format

Mantissa is a pure fraction in sign-magnitude form. The decimal number 0.239 × 213
has the following hexadecimal representation (without normalization and rounding off :
- A.
0D 24
- B.
0D 4D
- C.
4D 0D
- D.
4D 3D
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Correct answer: D
Key idea: store the exponent in excess-64 and encode the mantissa as an 8-bit pure fraction (mantissa/256); do not normalize or round — truncate the fractional part.
Write the value as mantissa × 2^exponent. The given number is 0.239 × 2^13, so the true exponent is 13 and the fractional part to encode is 0.239.
Encode the mantissa as an 8-bit pure fraction: multiply 0.239 by 256 to get 0.239 × 256 = 61.184. Without rounding, truncate to 61 (decimal) = 0x3D. This gives mantissa = 61/256 ≈ 0.23828125.
Encode the exponent using excess-64: stored exponent = 13 + 64 = 77 (decimal) = 0x4D.
Assemble the 16-bit word: sign bit = 0 (positive), stored exponent = 0x4D (placed in bits 14..8), mantissa byte = 0x3D (bits 7..0). The final hexadecimal bytes (high-order first) are 0x4D 0x3D.
Final answer: 4D 3D
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