Today’s problem — free all day, every step. Every day has one.
Net of a cube — the opposite face
The figure is the net of a cube. Which face is opposite face A when it is folded?
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The pattern behind it: Seeing it move
Work out where the pieces land after a fold, cut or stack.
In this one. In a straight strip of three squares, the two end squares always fold up to face each other — so they are opposite; find every such strip, and the two faces left over must be the last pair.
How to spot it
Words like 'folded', 'cut along the dotted line' or 'stacked' appear beside a shape, and the question asks for a length or angle that only makes sense once the pieces are in their new positions.
Common mistake
Children try to calculate the answer before working out where the pieces actually end up, skipping the visualisation step that the whole question depends on.
Try one like it
Challenging Rectangle — a square bitten out of one corner A rectangle has a length of 18 cm and a width of 9 cm. A square of side 4 cm is cut from one corner. Find the area of the remainin…The 33 problem patterns
All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.
A PDF, and a note when new solutions go up.