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Example—Multiply 234 by 512 in one line.
| 2 | 3 | 4 | multiplicand |
| h | m | r | |
| 5 | 1 | 2 | multiplier. |
| l | t | n | |
| 119808 | |||
2 × 4 = 8 put down 8 as part of the product.
n r
2 × 3 = 6 call d
n m
1 × 4 + d = 10 put down 0 and carry 1, call q
t r
2 × 2 + q = 5 call j
n h
5 × 4 + j = 25
l r
1 × 3 + 25 = 28 put down 8 and carry 2, call h'
t m
1 × 2 + h' = 4 call z
t h
5 × 3 + z = 19 put down 9 and carry 1, call q'
l m
5 × 9 + q' = 11 put down.
l n
Which in words would be as follows:
Twice 4 are 8, put down 8.
Twice 3 are 6 and (once 4) 4 are 10, put down 0 and carry 1.
Twice 2 are 4 and 1 are 5, and (5 times 4) 20 are 25, and (3 times 1) 3 are 28, put down 8 and carry 2.
Once 2 are 2, and 2 are 4, and (5 times 3) 15, are 19, put down 9 and carry 1; 5 times 2 are 10, and 1 are 11, which put down.
This method may be extended to any number of
