Elementary arithmetic, with brief notices of its history... by Robert Potts.

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to 3 and 6 factors each equal to 5. Sometimes 34x50 is more
briefly denoted by 34.56.
7. PROB. To find the quotient of two numbers which consist of one or of
two digits.
Let it be required to find the quotient arising from 15 divided by
5. The quotient denotes the number of times the divisor is contained
in, or can be subtracted from, the dividend.
Let 5 be subtracted successively from 15. First. 5 subtracted
from 15 leaves 10. Secondly. 5 from 10 leaves 5. Thirdly. 5 from
5 leaves 0. So that 5 can be subtracted 3 times from 15, or 5 is;
contained 3 times in 15, or 15 divided by 5 gives 3 for the quotient.
This will also appear from the fact that division being the reverse
of multiplication, since 3 times a is 15, it follows that 5 is contained
3 times in 15.
The following statements exhibit how many times each of the nine
digits is exactly contained in numbers consisting of one or two digits:

1 divided by 1 gives 1
2,,, 2
3,,,, 3
4,,,, 4
5,,,, 5
6,,,, 6
7,,,,
8,,,, 8
9,,,, 9
4 divided by 4 gives 1
8,,,, 2
12,,,, 3
16,,,, 4
20,,, 5
24,,,, 6
28,,,, 7
32,,,, 8
36,,,, 9
7 divided by 7 gives 1
14,,,, 2
21,,,, 3
28,,,, 4
35,,,, 5
42,,,, 6
49,, 7
56,,,, 8
63,,,, 9

2 divided by 2 gives 1
4,,,, 2
6,,,, 3
8,,,, 4
10,,,, 5
12,,, 6
14,,, 7
16,,,, 8
18, 9
5 divided by 5 gives 1
10,,,, 2
15,,,, 3
20,,,, 4
25,,,, 5
30,,,, 6
35,,,, 7
40,,,, 8
45,,,, 9
8 divided by 8 gives 1
16,,,, 2
24,,,, 3
32,,,, 4
40,,,, 5
48,,,, 6
56,,, 7
64,,,, 8
72,,, 9

3 divided by 3 gives 1
6,,,, 2
9,,,,
12,,,, 4
15,,,, 5
18,,,, 6
21,,,, 7
24,,,, 8
27,,,, 9
6 divided by 6 gives 1
12,,,, 2
18,,,, 3
24,,,, 4
30,,,, 5
36,,,, 6
42,,,, 7
48,,,, 8
54,,,, 9
9 divided by 9 gives 1
18,,,, 2
27,,,, 3
36,,,, 4
45,,, 5
54,,,, 6
63,,,, 7
72,,,, 8
81,,,, 9

8. PROB. To divide any number by a number of one digit.
The process depends on the following
Axiom. One number is contained in another as many times as the former
is contained in the several parts into which the latter can be
divided.