Page:Smith - Number Stories of Long ago (1919).djvu/70

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OF LONG AGO

so on, and if you do this you will find it about as easy to add with Roman numerals as with our own.

After learning to add, which he found quite easy, Caius learned to subtract, and that was also easy; but when he came to multiplying or dividing with Roman numerals he at once found himself in a great deal of trouble.

CCL

VII
CCCLXVIIII

DCXXVI

HOW CAIUS ADDED 257 AND 369

Caius had six I’s, so he wrote VI below; he had two V’s, so he wrote X below; he had one X, so he wrote X below that; he had two L’s, so he wrote C below; and he had five other C’s, so he wrote D below them

Although Caius learned how to add and subtract with Roman numerals, there was another method that was more common. He learned that pebbles were used in working with numbers. He found that he could draw lines on a board, — one to represent units, another to represent tens, and so on, — and that he could then place pebbles on these lines.
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