Date =
Title = Hexadecimal numbers
Objectives =
  • explain the use of hexadecimal numbers to represent binary numbers.
  • convert positive denary whole numbers (0-255) into 2-digit hexadecimal numbers and vice versa
  • convert between binary and hexadecimal equivalents of the same number
Keyword
  • Hexadecimal
Extension: http://www.teach-ict.com/gcse_computing/ocr/214_representing_data/units/quizzes_units.html

(g) explain the use of hexadecimal numbers to represent binary numbers.

http://www.cambridgegcsecomputing.org/representation-of-data-in-computer-systems-main
34: Hexadecimal Numbers

Questions:

  1. Explain why hexadecimal numbers are often used to represent binary numbers. (2)
  2. The pixels in RGB computer images are programmed by three, 8 bit numbers for the red, green and blue channels. These binary numbers are usually represented by their hexadecimal equivalents. In the following table insert the binary and hexadecimal equivalents for the following colours.(6)
Hex Colour table.png

(e) convert positive denary whole numbers (0-255) into 2-digit hexadecimal numbers and vice versa

help here: http://www.teach-ict.com/gcse_computing/ocr/214_representing_data/number/miniweb/pg7.htm

Denary > Hex method
Divide by 16 for the second digit and use the remainder as the first digit
182 = 11 remainder 6 > B6
Convert the following numbers from DENARY to HEX in your books, showing your workings:
  • 96
  • 201
  • 141
In pairs, give your partner 3 DENARY numbers and ask them to covert them to HEX. Check their answers using green pen

Hex > Denary method
Multiply the second digit by 16 and add the first digit
2E = (2 * 16) + E > 32+14 > 46
Convert the following numbers from HEX to DENARY in your books, showing your workings:
  • 9C
  • EB
  • 23
In pairs, give your partner 3 HEX numbers and ask them to covert them to DENARY. Check their answers using green pen