Letter Codes & Number Codes
<p>Code questions are a classic part of verbal reasoning. You are given a word and its code, and you have to crack the pattern so you can encode or decode other words. Think of yourself as a codebreaker!</p>
<h2>Letter Codes</h2>
<p>In letter code questions, each letter in a word is replaced by a different letter according to a rule.</p>
<p><strong>Worked Example:</strong> If CAT is coded as DBU, what is DOG coded as?</p>
<p>Step 1: Compare each letter of CAT with DBU:<br>
C → D (moved forward 1 in the alphabet)<br>
A → B (moved forward 1)<br>
T → U (moved forward 1)<br>
The rule is: each letter moves forward by 1.</p>
<p>Step 2: Apply the rule to DOG:<br>
D → E, O → P, G → H. Answer: EPH.</p>
<p><strong>Worked Example:</strong> If FISH is coded as HRUJ, what is BIRD coded as?</p>
<p>F → H (+2), I → R (+9)... wait, that is not consistent. Let us recheck: F → H (+2), I → R? I is the 9th letter, R is the 18th — that is +9. This does not look like a single shift. Let me reconsider: perhaps each letter shifts by a different amount. F(6)→H(8)=+2, I(9)→R(18)=+9, S(19)→U(21)=+2, H(8)→J(10)=+2. The I→R jump looks wrong. A real exam would use a consistent rule. Let me correct the example:</p>
<p>If FISH is coded as HKUJ, what is BIRD coded as?</p>
<p>F(6)→H(8)=+2, I(9)→K(11)=+2, S(19)→U(21)=+2, H(8)→J(10)=+2. Every letter shifts +2.<br>
BIRD: B(2)→D(4), I(9)→K(11), R(18)→T(20), D(4)→F(6). Answer: DKTF.</p>
<h2>Number Codes</h2>
<p>Each letter might be assigned a number. You use given examples to work out the assignment.</p>
<p><strong>Worked Example:</strong> If COLD = 3, 15, 12, 4 then what is HOT?</p>
<p>C=3 (3rd letter), O=15 (15th letter), L=12 (12th letter), D=4 (4th letter). The rule: each letter equals its position in the alphabet.<br>
H=8, O=15, T=20. Answer: 8, 15, 20.</p>
<h2>Mixed Codes</h2>
<p>Sometimes codes use a mixture of letters and numbers, or the rule involves reversing the word first, or using a different shift for each position. The key is always the same: compare the coded version with the original to find the pattern.</p>
<h2>Step-by-Step Approach</h2>
<ol>
<li>Write the original word and the code underneath, letter by letter</li>
<li>Work out the shift or substitution for each letter</li>
<li>Check if the shifts are all the same (simple shift) or follow a pattern (e.g., +1, +2, +3...)</li>
<li>Apply the pattern to the new word</li>
<li>Double-check by applying your rule back to the original example</li>
</ol>
<h2>Reverse Codes</h2>
<p><strong>Worked Example:</strong> If the code for STOP is POTS, what is the code for FLOW?</p>
<p>STOP → POTS is simply the word reversed. So FLOW reversed = WOLF.</p>
<h2>Two-Word Code Tables</h2>
<p>Sometimes you are given a table: CAT = MXG, COT = MXK, CUT = MXB. You can work out that C always = M, the second letter position uses a fixed code, and the third letter varies. By comparing, you can decode or encode new words.</p>
<h2>Practice Tips</h2>
<ul>
<li>Write out the alphabet with numbers (A=1, B=2, ... Z=26) on a reference card and use it during practice</li>
<li>Always check your rule against the given example before applying it to the question</li>
<li>If the shift seems inconsistent, look for other patterns: reversals, alternating shifts, or positional rules</li>
<li>Speed comes with practice — do a few code questions every day</li>
</ul>