Logical Reasoning · Codes, Relations & Directions
Coding-Decoding — Questions & Answers
Coding-decoding questions show how some words or numbers are written in a code and ask you to code or decode another. Find the rule — a letter shift, a reversal, or a substitution.
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How to approach
Work out each letter's value from the example: its place in the alphabet (A = 1), its place counted from Z, or a multiple. Check the rule on the example word, then add up the new word.
Compare the word with its code letter by letter. Look for a fixed shift, opposite letters (A↔Z), a reversed word, or alternating shifts. Apply exactly the same rule to the new word.
Line up each example word with its code: every letter keeps one digit. Build the letter-digit list, then code (or decode) the new word one letter at a time.
Read the key carefully and convert one symbol at a time, left to right.
5 solved Coding-Decoding questions
If A = 1 and LEMON = 59, then MELON = ?
Solution — answer C
Here each letter takes its place in the alphabet (A = 1, B = 2 … Z = 26), which gives LEMON = 59. So MELON = 13 + 5 + 12 + 15 + 14 = 59. (MELON uses the same letters as LEMON, so the total is unchanged.)
4 steps · reveal one at a timeStep 1: Find the pattern
We are given that A = 1. This suggests that letters are assigned values based on their alphabetical position. For example, B = 2, C = 3, and so on, up to Z = 26. Let's see if this rule works for the given word.
Step 2: Test the rule
Let's apply this rule to LEMON. L is the 12th letter, E is the 5th, M is the 13th, O is the 15th, and N is the 14th. Adding these values: 12+5+13+15+14=59. This matches the given value for LEMON.
Step 3: Calculate MELON
Now, let's find the value for MELON using the same rule. M is the 13th letter, E is the 5th, L is the 12th, O is the 15th, and N is the 14th. Summing these values: 13+5+12+15+14=59.
Step 4: The answer
So the answer is (C) 59. The word MELON uses exactly the same letters as LEMON, just in a different order, so their total sum based on alphabetical position remains unchanged.
In a certain code, PLANT is written as QMBOU. How is RIVER written in that code?
Solution — answer D
In PLANT → QMBOU, each letter moves 1 place forward (P→Q, L→M, A→B, N→O, T→U). Applying the same rule, RIVER → SJWFS.
4 steps · reveal one at a timeStep 1: Analyze the code
Let's look at the given example: PLANT is written as QMBOU. Our first task is to understand the rule or pattern that transforms PLANT into QMBOU.
Step 2: Discover the pattern
By comparing each letter, we can see a consistent change: P moves to Q, L to M, A to B, N to O, and T to U. This means each letter is shifted one place forward in the alphabet.
Step 3: Apply to RIVER
Now, we apply this same 'one place forward' rule to each letter in the word RIVER:\nR → S\nI → J\nV → W\nE → F\nR → S\nThis gives us the coded word SJWFS.
Step 4: The answer
So the answer is (D) SJWFS. Each letter in RIVER is moved one position forward in the alphabet to get SJWFS.
If PLATE is coded as 21403 and TRAIL as 05471, how is TAPIR coded?
Solution — answer B
Each letter keeps one digit: T = 0, A = 4, P = 2, I = 7, R = 5. So TAPIR = 04275.
4 steps · reveal one at a timeStep 1: Understand the coding
We are given two coded words: PLATE as 21403 and TRAIL as 05471. This type of question usually means each letter consistently maps to a specific digit. Our goal is to find the code for TAPIR.
Step 2: Find letter codes
Let's deduce the code for each letter by comparing the given words. From PLATE = 21403, we get P=2, L=1, A=4, T=0, E=3. From TRAIL = 05471, we confirm T=0, A=4, L=1, and find R=5, I=7.
Step 3: Assemble TAPIR's code
Now we have all the individual letter codes needed for TAPIR: T=0, A=4, P=2, I=7, R=5. We just need to put them together in the correct order to form the code for TAPIR.
Step 4: The answer
So the answer is (B) 04275. By substituting each letter with its corresponding digit (T=0, A=4, P=2, I=7, R=5), we get 04275.
Code key: B = 4, G = 9, M = 1, R = 6, T = 0, W = 3, K = 8, F = 5, S = 2, H = 7.
Using the key, what is the code for GTKS?Solution — answer B
Replace each letter by its digit: G = 9, T = 0, K = 8, S = 2, giving 9082.
4 steps · reveal one at a timeStep 1: Understand the Goal
We need to decode the word GTKS using the provided code key. Each letter in the word corresponds to a specific digit given in the key.
Step 2: Find Each Letter's Code
Let's find the digit for each letter in GTKS from the code key: G = 9, T = 0, K = 8, S = 2. We will replace each letter with its corresponding digit in order.
Step 3: Combine the Digits
Now, substitute the digits into the word GTKS in the correct sequence. G becomes 9, T becomes 0, K becomes 8, and S becomes 2. This gives us the code 9082.
Step 4: The answer
So the answer is (B) 9082. This is the direct result of replacing each letter in GTKS with its corresponding digit from the provided code key.
In a code language, (1) 'mi lo pa' means 'bright red flower'; (2) 'pa zu ki' means 'flower is fresh'; (3) 'lo ki ra' means 'red and fresh'. What is the code for 'bright'?
Solution — answer B
Take sentence 1 ('mi lo pa' = 'bright red flower'). 'red' is the only word in sentences 1 and 3, so it is 'lo'; 'flower' is the only word in sentences 1 and 2, so it is 'pa'. The only pair left is 'bright' = 'mi', so the answer is 'mi'.
4 steps · reveal one at a timeStep 1: Compare Sentences 1 and 3
Let's find the code for 'red'. Sentence (1) is 'mi lo pa' = 'bright red flower'. Sentence (3) is 'lo ki ra' = 'red and fresh'. The common word is 'red', and the common code is 'lo'. So, 'red' is 'lo'.
Step 2: Compare Sentences 1 and 2
Next, let's find the code for 'flower'. Sentence (1) is 'mi lo pa' = 'bright red flower'. Sentence (2) is 'pa zu ki' = 'flower is fresh'. The common word is 'flower', and the common code is 'pa'. So, 'flower' is 'pa'.
Step 3: Find Code for 'bright'
Now we know that 'red' is 'lo' and 'flower' is 'pa'. From sentence (1), 'mi lo pa' means 'bright red flower'. If 'lo' is 'red' and 'pa' is 'flower', then the remaining code 'mi' must mean 'bright'.
Step 4: The answer
So the answer is (B) mi, because by eliminating the codes for 'red' and 'flower' from the first sentence, 'mi' is the only code left for 'bright'.
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