Logical Reasoning
Analogy, Classification & Series
In a series, find the rule (the differences may themselves form a pattern) and give the next term. In an analogy, match the relationship of the first pair. In classification (odd one out), spot the item that breaks the rule.
Example 1: Find the next number: 2, 6, 12, 20, ___
Differences are 4, 6, 8, so add 10: 30.
Example 2: Complete the analogy: 5 : 25 :: 6 : ___
36 (each number squared).
Quick recap
- Series: find the rule (even in the differences).
- Analogy: match the relationship; classification: find the odd one out.
✓ Quick check
Find the next number: 1, 4, 9, 16, ___ ?
These are square numbers, so 5² = 25.
Which is the odd one out: 3, 5, 7, 9?
9 = 3 × 3 is composite; the others are prime.
Coding-Decoding (Advanced)
In coding-decoding, letters change by a rule — shifting by a fixed number, or using position values (A = 1 … Z = 26). Find the rule from the example, then apply it.
Example 1: If each letter moves forward by 2, what is the code for CAT?
C→E, A→C, T→V, so ECV.
Example 2: If A = 1, B = 2, …, what is the value of D?
D is the 4th letter, so 4.
Quick recap
- Find the shift or the position rule, then apply it.
- Position values: A = 1, B = 2, …, Z = 26.
✓ Quick check
If each letter moves forward by 2, the code for DOG is ___ ?
D→F, O→Q, G→I gives FQI.
If A = 1, B = 2, …, Z = 26, the value of the letter D is ___ ?
D is the 4th letter, so 4.
Direction Sense, Venn Diagrams & Puzzles
For direction sense, use the compass clockwise: North, East, South, West. A Venn diagram shows the overlap of groups. A 3×3 magic square using 1 to 9 has every line summing to 15, and in a number pyramid each brick is the sum of the two below it.
Example 1: Facing South, you turn right. Which way do you face?
West.
Example 2: In a number pyramid, the bricks below are 3 and 4. What is the brick above?
3 + 4 = 7.
Quick recap
- Compass clockwise: North, East, South, West.
- Magic square (1–9) line sum = 15; pyramid brick = sum of the two below.
✓ Quick check
In a 3×3 magic square using 1 to 9, each line sums to ___ ?
The magic sum is 15.
Facing North and turning right, you now face ___ ?
Turning right from North faces East.
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