WOLFRAM|DEMONSTRATIONS PROJECT

Lattice Method Multiplication Grids

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multiplicand
5
multiplier
3
view rotation
Multiplication by the lattice method shows all carries explicitly. Worksheets for the multiplication of
p
, an
m
-digit number, times
q
, an
n
-digit number, need
m×n
pairs of triangles for carries and last digits of elementwise products. Select the number
m
of decimal digits for multiplicand
p
and the number
n
of digits for the multiplier
q
, then rotate the resulting grid to emphasize either the
m×n
elementwise multiplications of digits or the additions of the resulting carries and last digits along diagonal columns. Note that the maximum number of digits in the result
p×q
is equal to the sum of digits
m+n
in multiplicand and multiplier.