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72
CHAPTER I—EGYPTIAN ARITHMETIC
[30

110 also he can take without difficulty. For 13 he has 110 of 10 equal to 1, and 110 of 3, by the table that precedes Problem 1, is 15110. Finally, 110 of 128 is 1280.

In the original our author seems to say that we must multiply 130 by 123 to get 23110. It may be that he did not mean to put a dot (the sign for fraction) over 23, but meant to say, Multiply 130 by 23 to get 23110. This is a correct statement but does not explain his solution. Following the method given in the other problems of this group, he should have said, Multiply 123 by 23110 to get 130.

Problem 31
A quantity, its 23, its 12, and its 17, added together, become 33. What is the quantity?

Multiply 1231217 so as to get 33.

  1 1231217
\ 2 41314128
\ 4 916114
\ 8 181317
  12 121314114
\ 14 141618128

Total 1414. 1414 times 1231217 makes 3212 plus the small fractions 1718114128128. 3212 from 33 leaves the remainder 12 to be made up by these fractions and a further product by a number yet to be determined.
1718114128128
taken as parts of 42 are
65143112112
making in all 1714, and requiring 31214 more to make 21,12 of 42.

Take 1231217 as applying to 42:

\ 1 42
\ 28 28
\ 12 21
\ 17 6
  Total 97.

That is, 1231217 applied to 42 gives 97 in all. 142 of 42, or 1, will be 197 of this, and 31214 will be 31214 times as much. Therefore we multiply 197 by 31214.

[1]\ 197 142 or 1 as a part of 42
\ 15616791776 121 " 2 " " " " 42
\ 1194 184 " 12 " " " " 42
\ 1388 1168 " 14 " " " " 42
  1. These multiplications do not represent the multiplication of 197, by 31214, but form a continuation of the multiplication at the beginning of the solution. But the partial products of