2 thousands, 3 hundreds, 5 tens, and 6 units.
Take each of these parts ten times, which, by (52), is the same as multiplying the whole number by 10, and it will then become
2 tens of thou. 3 tens of hun. 5 tens of tens, and 6 tens,
which is
2 ten-thou. 3 thous. 5 hun. and 6 tens.
This must be written 23560, because 6 is not to be 6 units, but 6 tens. Therefore 2356 × 10 = 23560.
In the same way you may shew, that in order to multiply by 100 you must affix two ciphers to the right; to multiply by 1000 you must affix three ciphers, and so on. The rule will be best caught from the following table:
| 13 × | 10 = | 130 |
| 13 × | 100 = | 1300 |
| 13 × | 1000 = | 13000 |
| 13 × | 10000 = | 130000 |
| 142 × | 1000 = | 142000 |
| 23700 × | 10 = | 237000 |
| 3040 × | 1000 = | 3040000 |
| 10000 × | 100000 = | 1000000000 |
58. I now shew how to multiply by one of the numbers, 2, 3, 4, 5, 6, 7, 8, or 9. I do not include 1, because multiplying by 1, or taking the number once, is what is meant by simply writing down the number. I want to multiply 1368 by 8. Write the first number at full length, which is
1 thousand, 3 hundreds, 6 tens, and 8 units.