Jack and Tree Height

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?




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Amazing Facts

Out of the Box

The phrase “thinking outside the box” was popularised from the solution to a topographical puzzle involving 9 dots in a box shape.