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Year 9 Computing — Text as numbers

Work out the code number a character is stored as, and how many bytes a piece of text needs.

Name: ________________________

  1. 1.Capitals are stored from 65 and small letters from 97. A computer puts a list of words in order by the code number of the first character. Which of these words does it put first?

    • a) cherry
    • b) banana
    • c) apple
    • d) Zebra

  2. 2.Digit characters run in order from 48, capitals from 65 and small letters from 97. Put these characters in order of the code number stored for each, smallest first.

    • capital B
    • small z
    • capital M
    • the digit character 7
    • small d

  3. 3.Each message is stored one character per byte, gaps included. Match each message to the number of bytes it needs.

    • YES
    • HELLO
    • OK NOW
    • GOODBYE
    • I AM HERE
    • 5
    • 9
    • 3
    • 6
    • 7

  4. 4.Capital A is stored as 65 and small a is stored as 97. How much bigger is the code for a small letter than the code for the capital of the very same letter?

  5. 5.The capital letters run in order from 65 and the small letters run in order from 97, twenty-six of each. Sort each code number by which kind of letter it stands for.

    Groups: A capital letter · A small letter

    • 88
    • 115
    • 78
    • 70
    • 99
    • 104

  6. 6.Capital A is stored as 65 and the capital letters carry straight on from there. Which capital letter is stored as 72?

  7. 7.A code with one byte per character can tell apart 256 different characters. Why is one byte per character not enough for the writing used around the world?

    • a) Every character needs a whole byte of its own even when it is only a letter
    • b) Punctuation marks and gaps are not characters and have to be stored some other way
    • c) Every language would need a computer built specially for it
    • d) The writing systems of the world need far more than 256 different characters between them

  8. 8.In a computer's character code, capital A is stored as 65 and the capital letters that follow carry straight on. What number is stored for capital D?

Answer key — Year 9 Computing — Text as numbers

  1. 1. d) Zebra
  2. 2. 1. the digit character 7 2. capital B 3. capital M 4. small d 5. small z
  3. 3. YES → 3; HELLO → 5; OK NOW → 6; GOODBYE → 7; I AM HERE → 9
  4. 4. 32
  5. 5. 70 → A capital letter; 99 → A small letter; 88 → A capital letter; 104 → A small letter; 78 → A capital letter; 115 → A small letter
  6. 6. H
  7. 7. d) The writing systems of the world need far more than 256 different characters between them
  8. 8. 68