231.--PLATES AND COINS.

Place twelve plates, as shown, on a round table, with a penny or orange

in every plate. Start from any plate you like and, always going in one

direction round the table, take up one penny, pass it over two other

pennies, and place it in the next plate. Go on again; take up another

penny and, having passed it over two pennies, place it in a plate; and

so continue your journey. Six coins only are to be removed, and when

these have been placed there should be two coins in each of six plates

and six plates empty. An important point of the puzzle is to go round

the table as few times as possible. It does not matter whether the two

coins passed over are in one or two plates, nor how many empty plates

you pass a coin over. But you must always go in one direction round the

table and end at the point from which you set out. Your hand, that is to

say, goes steadily forward in one direction, without ever moving

backwards.

[Illustration]

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