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185 stored as a signed 8-bit number?

  1. Oct 29, 2015 #1
    Several exercises in my textbook start with assumptions that confuse me. For example:

    • Assume 185 and 122 are signed 8-bit decimal integers stored in sign-magnitude format.

    • Assume 151 and 214 are signed 8-bit decimal integers stored in two's complement format.
    I am then to go on to find the sum or difference (varies by exercise) of the numbers and state if there is overflow, underflow, or neither.

    But...isn't the maximum number that can be represented here 2^7−1=127?
  2. jcsd
  3. Oct 29, 2015 #2


    Staff: Mentor

    These questions don't make sense to me, either. 127 is the largest number that can be stored as a signed 8-bit integer. So three of the numbers listed above are already too large to fit in 8 bits (with one bit for the sign).
  4. Oct 29, 2015 #3

    Vanadium 50

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    And doesn't the question ask you if there are overflows or underflows?
  5. Oct 29, 2015 #4


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    Staff: Mentor

    Can you provide a sample: one exercise, together with the textbook's answer?
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