way a number can be multiplied by a figure which is accompanied by ciphers, as, for example, 8000. For 8000 is 8 × 1000, and therefore (55) you must first multiply by 8 and then by 1000, which last operation (57) is done by placing 3 ciphers on the right. Hence the rule in this case is, multiply by the simple number, and place the number of ciphers which follow it at the right of the
EXAMPLE.
| Multiply | 1679423800872 |
|---|---|
| by | 60000 |
| 100765428052320000 |
- EXERCISES.
What is 1007360 × 7? Answer, 7051520.
123456789 × 9 + 10 and 123 × 9 + 4?—Ans. 1111111111 and 1111.
What is 136 × 3 + 129 × 4 + 147 × 8 + 27 × 3000?—Ans. 83100.
An army is made up of 33 regiments of infantry, each containing 800 men; 14 of cavalry, each containing 600 men; and 2 of artillery, each containing 300 men. The enemy has 6 more regiments of infantry, each containing 100 more men; 3 more regiments of cavalry, each containing 100 men less; and 4 corps of artillery of the same magnitude