Number Codes
Number codes questions show a word that has been turned into a number code, usually by a rule such as each letter's position in the alphabet (A=1, B=2, up to Z=26), sometimes with a number added, subtracted or doubled, and ask you to apply the same rule to a new word or to decode a number sequence back into a word. They are a common question type in GL Assessment style 11+ verbal reasoning papers.
Before you start
Make sure you're comfortable with these topics first:
Method
- Study the example word and its code carefully, and match each letter to its number one at a time.
- Check whether the rule is simply the alphabet position (A=1 up to Z=26), or whether a number has been added, subtracted, doubled, or counted from Z backwards instead.
- If two example words are given, check the rule against both, since a rule that only fits one word by coincidence is the wrong rule.
- Apply the confirmed rule letter by letter to build the new code, or apply it in reverse, one number at a time, to turn a code back into letters.
- Write your letters or numbers out in the same order as the original word or code.
- Check the first and last letter of your answer carefully, since these are the easiest place to make a slip.
Worked example
If the code for BAT is 2-1-20, what is the code for CUP?
- Compare BAT with its code: B=2, A=1, T=20.
- This matches each letter to its position in the alphabet (A=1, B=2, and so on), so the rule is simply alphabet position.
- Apply the rule to CUP: C is the 3rd letter, U is the 21st letter, P is the 16th letter.
- Write the numbers in the same order as the letters: 3-21-16.
- Final answer: 3-21-16.
Practice questions
Try each question, then tap to reveal the answer.
Exam-style questions
Written in the style of a 11+ exam paper, with a full mark scheme.
The code for LAMP is 12-1-13-16. Using the same alphabet-position rule, what is the code for BIRD? Show your working.
In a code, each letter's alphabet position has 4 added to it. The code for LAMP is 16-5-17-20. Which word does the code 11-19-16-8 represent? Show your working.
If BAT = 4-3-22 and SUN = 21-23-16, using the same rule for both words, what is the code for HEN? Show your working.
Free printable worksheet
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