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A recreation in which a board containing a picture to be painted is made up of numbered areas, each number corresponding to a color of paint to be applied.

A paint-by-number kit

A recreation in which a board containing a picture to be painted is made up of numbered areas, each number corresponding to a color of paint to be applied.

A completed paint-by-number painting

A recreation in which a board containing a picture to be painted is made up of numbered areas, each number corresponding to a color of paint to be applied.

In the 1960s, the first images of Mars were completed like a painting by numbers.