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Table of Contents

SECTION III. MULTIPLICATION.

q times, we write,

a/b = q, or a : b = q,

which in old books is often found written thus:

a ÷ b = q.

  1. If I divide 156 into several parts, and find how often 13 is contained in each of them, it is plain that 156 contains 13 as often as all its parts together. For example, 156 is made up of 91, 39, and 26. Of these
91contains 137 times,
39contains 133 times,
26contains 132 times;

therefore 91 + 39 + 26 contains 13 7 + 3 + 2 times, or 12 times.

Again, 156 is made up of 100, 50, and 6.

Now100 contains13 7 timesand 9 over,
50 contains13 3 timesand 11 over,
6 contains13 0 times [9]and 6 over.

Therefore 100 + 50 + 6 contains 13 7 + 3 + 0 times and 9 + 11 + 6 over; or 156 contains 13 10 times and 26 over. But 26 is itself 2 thirteens; therefore 156 contains 10 thirteens and 2 thirteens, or 12 thirteens.

  1. The result of the last article is expressed by saying, that if

a = b + c + d, then

a=b+c+d
mmmm
  1. In the first example I
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