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Ewa's Eggs

Age 11 to 14 Challenge Level:


Tomek accidentally knocked over Ewa's basket of eggs. Wishing to make amends he offers to pay as they are all broken.

Ewa, a mathematician, recognising a fellow mathematician's embarrassment, replies:
"I put the eggs into the basket in groups of 7 and noticed that I could easily have divided them into piles of 2, 3, 4, 5 or 6 and always have one left over."

What should Tomek offer to pay? (Eggs currently cost 95p a dozen)