EXAMPLE.
Suppose the number thought of to be 6
1. Let him double it 12
2. Add 4 16
3. Multiply by 5 80
4. Add 12 92
5. Multiply by 10 920
Let him inform you what is the number produced. You must then, in every
case, subtract 320; the remainder is, in this example, 600; strike off
the 2 ciphers, and announce 6 as the number thought of.