Solving Type 4 Questions

Type 4 questions combine the rule-identification skills from Type 1 with the option-testing format of a multiple-choice question. You see Set A and Set B, identify the rules, and then determine which of four options belongs to a specified set. This lesson provides a complete strategy for handling these questions efficiently.

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The Format Revisited

You are shown:

1. Set A — six boxes following Rule A
2. Set B — six boxes following Rule B
3. A question — "Which of the following belongs to Set A?" (or Set B)
4. Four options — A, B, C, D

One option is correct. The other three either belong to the other set, satisfy neither rule, or are designed to look plausible.

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Strategy 1: Identify the Rule, Then Test Options

This is the standard, reliable approach.

Step 1: Identify the Rule

Use SCANS to determine the rule for the specified set (e.g., if asked "Which belongs to Set A?", focus on Set A's rule).

Step 2: Test Each Option

For each option, check: does it satisfy the rule?

• If yes → This is likely the answer
• If no → Eliminate it

Step 3: Confirm

If only one option satisfies the rule, select it. If multiple seem to satisfy it, re-examine your rule — you may have an incomplete or incorrect rule.

Worked Example

Set A rule (identified via SCANS): Total number of sides is 12.

Options:

• Option A: Two hexagons (6+6 = 12) ✓
• Option B: Three pentagons (5+5+5 = 15) ✗
• Option C: Four triangles and one circle (3+3+3+3+0 = 12) ✓
• Option D: One hexagon and one pentagon (6+5 = 11) ✗

Two options satisfy the rule! This means the rule is incomplete — there must be a second condition. Go back to Set A and look for an additional constraint.

Re-examination: Perhaps the rule is "total sides = 12 AND all shapes are the same type." Check Set A boxes:

• Two hexagons (same type, 12) ✓
• Three squares (same type, 12) ✓
• Four triangles (same type, 12) ✓

Revised rule: Total sides = 12 AND all shapes are the same type.

Re-test options:

• Option A: Two hexagons — same type ✓, total 12 ✓ → Correct
• Option C: Four triangles and one circle — not same type ✗

Answer: Option A

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Strategy 2: Elimination (When the Rule Is Hard to Identify)

If you cannot fully identify Set A's rule, use Set B's rule to eliminate options:

Step 1: Identify Set B's Rule

If Set B's rule is easier to spot, identify it.

Step 2: Eliminate Options That Fit Set B

Any option that satisfies Set B's rule cannot be the answer (since the question asks for Set A).

Step 3: Among Remaining Options, Select the Most Plausible

If elimination leaves one option, select it. If it leaves two or three, look for the one that seems most consistent with Set A's visual appearance.

Worked Example

Question: Which belongs to Set A?

Set B rule (easily identified): All shapes are circles.

Options:

• Option A: Three circles → Fits Set B → Eliminate
• Option B: Two circles, one square → Not all circles → Not Set B
• Option C: One hexagon, one triangle → Not all circles → Not Set B
• Option D: Four circles → Fits Set B → Eliminate

Remaining: Options B and C. Now look at Set A more carefully to distinguish between them.

Set A observation: Every Set A box contains exactly 3 shapes. Option B has 3 shapes. Option C has 2 shapes.

Answer: Option B (3 shapes, consistent with Set A's pattern).

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Strategy 3: The "Best Fit" Approach (Under Time Pressure)

If you are running low on time:

1. Quick scan Set A — note the first obvious feature (e.g., "lots of black shapes", "always 4 shapes")
2. Check options — which one matches the obvious feature?
3. Select and move on

This is less rigorous but faster. It works well for simpler questions and as a fallback when time is critical.

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How to Handle Compound Rules in Type 4

Compound rules create the most common trap in Type 4: options that satisfy one condition but not both.

The Trap Structure

If Set A's rule is "A AND B," the four options are typically: