In the following examples the first two lines are the multiplicand and multiplier; and the number of decimals to be retained will be seen from the results.

·4471618 33·166248 3·4641016
3·7719214 1·4142136 1732·508
37719214 033166248 346410160
8161744  63124141 8052371 
15087686 3316625 346410160
1508768 1326650 242487112
264034 33166 10392305
3772 13266 692820
2263 663 173205
38 33 2771
30 10 6001·58373
1·6866591 2  
  46·90415  

Exercises may be got from article (143).

155. With regard to division, take any two numbers, for example, 16·80437921 and 3·142, and divide the first by the second, as far as any required number of decimal places, for example, five. This gives the following:

3·142) 16·804 379 21(5·34830
  15·710  
  1·0943  
  9426  
  15177  
 (A)  12568  
2609 2609 9
2514 2513
95 96 32
94 94 26
1 2 061

Now cut off by a vertical line, as in (153), all the figures which come on the right of the first figure 2, in the last remainder 2061. As in multiplication, we may obtain all that is on the left of the vertical line by an abbreviated method, as represented at (A). After what has been said on multiplication, it is useless to go further into the detail; the following rule will be sufficient: To divide one decimal by another, retaining only n places: Proceed one step in the ordinary division, and determine, by (150), in what place is the quotient so obtained; proceed in the ordinary way, until the number of figures remaining to be found in the quotient is less than the number of figures in the divisor: if this should be already the case, proceed no further in the ordinary way. Instead of annexing a figure or cipher to the remainder, cut off a figure from the divisor, and proceed one step with this curtailed divisor as usual, remembering, however, in multiplying this divisor, to carry the nearest ten, as in (154), from the figure which was struck off; repeat this, striking off another figure of the divisor, and so on, until no figures are left. Since we know from the beginning in what place the first figure of the quotient is, and also how many decimals are required, we can tell from the beginning how many figures there will be in the whole quotient. If the divisor contain more figures than the quotient, it will be unnecessary to use them: and they may be rejected, the rest being corrected as in (151): if there be ciphers at the beginning of the divisor, if it be, for example,

·003178, since this is  ·3178  ,
100

divide by ·3178 in the usual way, and afterwards multiply the quotient by 100, or remove the decimal point two places to the right. If, therefore, six decimals be required, eight places must be taken in dividing by ·3178, for an obvious reason. In finding the last figure of the quotient, the nearest should be taken, as in the second of the subjoined examples.

Places required,   2   8
Divisor, ·41432   3·1415927
Dividend, 673·1489       2·71828180
  41432     2·51327416
  258828   20500764
  248592   18849556
    10237 [21] 1651208
  8286   1570796
  1951   80412
  1657   62832
  294   17580
  290   15708
  4   1872
   4   1571
  0   301
  283
  18
  19
Quotient, 1624·71   ·86525596

Examples may be obtained from (143) and (150).