NUMBER STORIES
work in the book which he wrote more than seven centuries ago. He first wrote the multiplicand; above that he placed the multiplier; and above that he wrote the product. This is our plan turned upside down. If you could ask Leonardo why he turned the work upside down, he would say that his work was right, but ours is upside down. It all depends on how we are taught.
392
8
49
HOW LEONARDO MULTIPLIED
From Leonardo’s arithmetic of 1202. It represents the multiplication of 49 by 8, the product being 392
It was about three hundred years after Leonardo that Cuthbert Tonstall (tŭn'stăl) was born in England. In those days it was still the custom in most countries to compute by counters, but Cuthbert went to a school where they taught the new method. In 1522 he published the first arithmetic printed in England. Although this was about a hundred
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