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Year 8 Computing — Bigger binary numbers

Read and write binary numbers with several places, and work out how many different values a given number of bits can hold.

Name: ________________________

Before you start

Move along this line and think about which binary places you would need to reach each point.

048121620242832

The points that need only a single 1 — 1, 2, 4, 8, 16, 32 — are the place values themselves. Everything else is built by adding a few of them together.

  1. 1.Sort each binary number by whether it is odd or even.

    Groups: Odd · Even

    • 10000
    • 1011
    • 1001
    • 1100
    • 10101
    • 11110

  2. 2.How many different values can be written with 5 bits?

  3. 3.What is the binary number "1010101" worth as an ordinary number?

  4. 4.The binary number "101100" sits at one of these points. Tap it.

    Mark the line with an X.

    0816243240485664

  5. 5.Put these binary numbers in order, smallest first.

    • 10001
    • 100100
    • 1010
    • 101
    • 1101

  6. 6.Match each binary number to its ordinary value.

    • 1000
    • 1111
    • 10010
    • 11000
    • 100000
    • 8
    • 18
    • 24
    • 15
    • 32

  7. 7.Write the number 37 in binary.

  8. 8.A byte is eight bits. How many different values can one byte hold?

    • a) 128
    • b) 64
    • c) 512
    • d) 256

Answer key — Year 8 Computing — Bigger binary numbers

  1. 1. 1011 → Odd; 1100 → Even; 10101 → Odd; 11110 → Even; 1001 → Odd; 10000 → Even
  2. 2. 32
  3. 3. 85
  4. 4. 44
  5. 5. 1. 101 2. 1010 3. 1101 4. 10001 5. 100100
  6. 6. 1000 → 8; 1111 → 15; 10010 → 18; 11000 → 24; 100000 → 32
  7. 7. 100101
  8. 8. d) 256