71. BCD code is
A. non-weighted
B. the same thing as binary numbers
C. a binary code
D. an alphanumeric code

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72. Which of the following 4-bit combinations is/are invalid in the BCD code?
A.1010
B.10
C.101
D.1000

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73. Octal coding involves grouping the bits in
A. 5's
B. 7's
C. 4's
D. 3's

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74. In Excess-3 code each coded number is than in BCD code.
A. four larger
B. three smaller
C. three larger
D. much larger

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75. Which numbering system uses numbers and letters as symbols?
A. decimal
B. binary
C. octal
D. hexadecimal

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76. To convert a whole decimal number into a hexadecimal equivalent, one should divide the decimal value by
A.2
B.8
C.10
D.16

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77. A logic gate is an electronic circuit which
A. makes logic decision
B. allows electron flow only in one direction
C. works on binary algebra
D. alternates between 0 and 1 values

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