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Class 8 Computer Science — Hexadecimal numbers

Read a hexadecimal number, turn it into decimal or into binary, and say why programmers write bits this way.

Name: ________________________

  1. 1.Two hexadecimal digits are written side by side. What is the largest decimal number the pair of them can hold between them?

    • a) 255
    • b) 256
    • c) 99
    • d) 128

  2. 2.Write the decimal number 45 in hexadecimal. Use two hexadecimal digits.

  3. 3.Which point on the line is the hexadecimal number 3A written in decimal?

    Mark the line with an X.

    01020304050607080

  4. 4.Put these hexadecimal numbers in order, smallest first.

    • 1F
    • FF
    • 4D
    • 2A
    • B0

  5. 5.Write the hexadecimal number A7 as eight binary bits.

  6. 6.Write the decimal number 200 in hexadecimal. Use two hexadecimal digits.

  7. 7.Match each hexadecimal digit to the four bits it stands for.

    • 4
    • 7
    • 9
    • D
    • E
    • 1110
    • 0100
    • 1001
    • 1101
    • 0111

  8. 8.The binary number 11010110 is split down the middle into two groups of four bits. Write those eight bits as two hexadecimal digits.

Answer key — Class 8 Computer Science — Hexadecimal numbers

  1. 1. a) 255
  2. 2. 2D
  3. 3. 58
  4. 4. 1. 1F 2. 2A 3. 4D 4. B0 5. FF
  5. 5. 10100111
  6. 6. C8
  7. 7. 4 → 0100; 7 → 0111; 9 → 1001; D → 1101; E → 1110
  8. 8. D6