Colour and Shading Patterns

In UCAT Abstract Reasoning, "colour" does not mean the full spectrum of colours you see in everyday life. The UCAT uses a limited palette — typically black (filled), white (outline only), grey (mid-tone fill), and occasionally striped or hatched patterns. Understanding how these shading options are used to construct rules is essential.

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The Shading Palette

Shading	Visual description	Common label
Black	Completely filled in, solid	Filled, solid, dark
White	Outline only, no fill	Empty, outline, open
Grey	Mid-tone fill, lighter than black	Grey, mid-shade
Striped/hatched	Filled with parallel lines (horizontal, vertical, or diagonal)	Striped, lined, hatched
Dotted	Filled with a dot pattern (less common)	Dotted, spotted

Important: When we say "colour" in AR, we almost always mean shading/fill. The UCAT does not typically use colours like red, blue, or green — everything is greyscale or patterned.

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Category 1: Uniform Shading Rules

The simplest shading rule: all shapes in each box share the same shading.

Worked Example

Set A:

• Box 1: Three black circles
• Box 2: Two black triangles, one black square
• Box 3: One black hexagon, one black pentagon
• Box 4: Four black rectangles
• Box 5: One black arrow, two black diamonds
• Box 6: Two black circles, one black star

Rule: Every shape in every box is black (uniformly filled).

Set B might have: every shape is white (outline only). Or it might have a completely different rule — never assume Set B is simply the "opposite" of Set A.

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Category 2: Proportion-Based Shading Rules

Many shading rules are about the proportion or count of shapes with each shading type.

Common Proportion Rules

Rule	Description
"More black than white"	In every box, the count of black shapes exceeds the count of white shapes
"Equal numbers of black and white"	Each box has the same number of black shapes as white shapes
"Exactly one grey shape"	Every box contains precisely one grey shape
"Majority shading matches the largest shape"	The most common fill in the box matches the fill of the largest shape

Worked Example: Equal Black and White

Set A:

• Box 1: Two black squares, two white circles (2 black, 2 white) ✓
• Box 2: One black triangle, one white hexagon (1 black, 1 white) ✓
• Box 3: Three black pentagons, three white rectangles (3 black, 3 white) ✓
• Box 4: One black diamond, one white arrow (1 black, 1 white) ✓
• Box 5: Two black circles, two white triangles (2 black, 2 white) ✓
• Box 6: One black hexagon, one white star (1 black, 1 white) ✓

Rule: The number of black shapes always equals the number of white shapes.

Test shape: Three black circles, two white squares.

• 3 black ≠ 2 white → Does not satisfy the rule.
• Answer: Not Set A. Check Set B or answer Neither.

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Category 3: Conditional Shading Rules

These are among the hardest shading rules because the shading depends on another attribute. You must identify two linked features, not just one.

Common Conditional Shading Rules

• "Circles are always black; triangles are always white" (shading linked to shape type)
• "Large shapes are always grey; small shapes are always black" (shading linked to size)
• "Shapes in the top half of the box are black; shapes in the bottom half are white" (shading linked to position)
• "Shapes with an odd number of sides are striped; shapes with an even number of sides are solid" (shading linked to side count)

Worked Example: Shading Linked to Shape Type

Set A:

• Box 1: Black circle, white triangle, white square
• Box 2: Black circle, black circle, white pentagon, white hexagon
• Box 3: Black circle, white rectangle, white diamond, white arrow
• Box 4: Black circle, black circle, black circle, white triangle
• Box 5: Black circle, white star, white hexagon
• Box 6: Black circle, white parallelogram

Rule: Circles are always black. Non-circles are always white.

Why this is hard to spot: You might initially think "there is always at least one black shape" — which is true, but that is the consequence of the rule, not the rule itself. The actual rule links shading to shape type. If you tested a shape with a white circle, it would violate the rule even though there might be a black triangle making "at least one black shape" true.

Test shape: One white circle, two black triangles.

• Circle is white (should be black) → violates the rule.
• Triangles are black (should be white) → also violates.
• Answer: Not Set A.

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Category 4: Shading Sequences