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Try different possible starting pairs and work systematically from there.
If one person takes 10 minutes to cross the bridge, and another takes 7 minutes, how can they all cross in just 17 minutes?
If A is the quickest to cross, then B, then C, then D, can you describe each of the strategies in terms of As, Bs, Cs and Ds, and then identify the difference?
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Place the 16 different combinations of cup/saucer in this 4 by 4 arrangement so that no row or column contains more than one cup or saucer of the same colour.
The letters of the word ABACUS have been arranged in the shape of a triangle. How many different ways can you find to read the word ABACUS from this triangular pattern?