51. When representing in the following code, the consecutive decimal numbers differ only in one bit—

1. 1. Excess - 3

   
   
   

   2. Gray

   
   
   

   3. BCD

   
   
   

   4. Hexadecimal

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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52. The main drawback of digital system is that—

1. 1. It is difficult to design

   
   
   

   2. It is not a precise system

   
   
   

   3. The real world is mainly analog

   
   
   

   4. Digital circuits are prone to noise

   
   
   

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1. View Hint View Answer Discuss in Forum

   The main drawback of digital system is that the real world is mainly analog.

   Correct Option: C

   The main drawback of digital system is that the real world is mainly analog.

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53. Modulo-2 addition is represented by—

1. 1. f = AB + BA

   
   
   

   2. f = AB + A B

   
   
   

   3. f = AB

   
   
   

   4. f = AB + A' B + BC

   
   
   

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1. View Hint View Answer Discuss in Forum

   Modulo-2 means, f = A ⊕ B = AB + BA.

   Correct Option: A

   Modulo-2 means, f = A ⊕ B = AB + BA.

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54. In Boolean algebra if F = (A + B). ( A + C), then—

1. 1. F = AB + AC

   
   
   

   2. F = AB + A B

   
   
   

   3. F = AC + AB

   
   
   

   4. F = AA + AB

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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55. Minimum no. of NAND gates require to implement the logic Y = AB + A + B + C

1. 1. 0

   
   
   

   2. 2

   
   
   

   3. 3

   
   
   

   4. 4

   
   
   

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1. View Hint View Answer Discuss in Forum

   Given Y = AB + A + B + C
   or Y = A + B + A + B C
   or Y = 1 + B + B C
   or Y = 1
   Therefore, no NAND gates required to implement the logic.

   Correct Option: A

   Given Y = AB + A + B + C
   or Y = A + B + A + B C
   or Y = 1 + B + B C
   or Y = 1
   Therefore, no NAND gates required to implement the logic.

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