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Class 7 Computer Science — Adding binary numbers

Add two binary numbers place by place, carrying into the next place whenever a column comes to more than one.

Name: ________________________

  1. 1.Add the binary numbers "1010" and "1010". Write the answer in binary.

  2. 2.Add the binary numbers "110" and "11". Write the answer in binary.

  3. 3.Add the binary numbers "1101" and "101". Write the answer in binary.

  4. 4.Add the binary numbers "11" and "1". Write the answer in binary.

  5. 5.Put these binary additions in order of their answers, smallest first.

    • 100 + 11
    • 1000 + 101
    • 110 + 100
    • 10 + 1
    • 11 + 10

  6. 6.Sort each addition by whether its right-hand column produces a carry.

    Groups: Produces a carry · No carry

    • 10 + 1
    • 1001 + 1001
    • 11 + 1
    • 101 + 11
    • 100 + 10
    • 1000 + 111

  7. 7.Add the binary numbers "1011" and "110". Write the answer in binary.

  8. 8.Add the binary numbers "110" and "10". Write the answer in binary.

Answer key — Class 7 Computer Science — Adding binary numbers

  1. 1. 10100
  2. 2. 1001
  3. 3. 10010
  4. 4. 100
  5. 5. 1. 10 + 1 2. 11 + 10 3. 100 + 11 4. 110 + 100 5. 1000 + 101
  6. 6. 1001 + 1001 → Produces a carry; 10 + 1 → No carry; 11 + 1 → Produces a carry; 100 + 10 → No carry; 101 + 11 → Produces a carry; 1000 + 111 → No carry
  7. 7. 10001
  8. 8. 1000