Two's Complement Quiz 2(F4 ICT)

Arrange the following 11-bit two's complement representations in descending orders: (P): 110 1111 1111 (Q) 111 1111 1111 (R) 101 1111 1111 (S) 110 0111 1111

• (P) > (Q) > (R) > (S)
• (Q) > (R) > (S) > (P)
• (Q) > (P) > (S) > (R)
• (S) > (R) > (Q) > (P)

A computer uses 4-bit two's complement representation to store signed integers. Which of the following calculations involves an overflow error?

• 2+2+2+1
• 5-3+2
• -3-3-2
• 3+3+2

A computer uses 8-bit two's complement representation to store signed integers. Which of the following calculations involves an overflow error?

• 64-10+20
• 64+20+20
• 93+20+20
• 65-40+80

Joe's computer uses 8-bit two's complement representation to store numbers. She increments a number by 4, then an overflow error occurs. What is the number X?

• 1000 0111
• 1111 1111
• 0111 1011
• 0111 1100

Which of the following additon of two 8-bit two's complement representations will generate an overflow error?

• 0101 1100 + 0010 0011
• 0101 1100 + 1010 1111
• 0101 1100 + 1110 1111
• 0101 1100 + 0010 1111

Which of the following subtraction of two 8-bit two's complement representations will generate an overflow error?

• 0101 1100 - 0010 0011
• 0101 1100 - 1110 0011
• 1101 1100 - 1110 0011
• 1001 1100 - 0110 0011

A computer uses 10-bit two's complement representation for calculations. After performing this calculation, X+Y, the computer returns Z as the answer. Under what conditions would an overflow error during this calculation? (1) The signs of X, Y are the same, but different from Z. (2) X + Y equals to 512. (3) X + Y equals to -512.

• (1) only
• (2) only
• (1) and (2) only
• (2) and (3) only