The method traditionally used for multiplying two numbers of two or more digits is long multiplication
, but this is quite an abstract process which is difficult to understand for many children. Grid Multiplication
(also known as the Grid Method
) is now taught in schools as an intermediate stage before long multiplication.
With grid multiplication
, the two numbers to be multiplied are split (partitioned
) up into their tens and units components - e.g. 34 = 30 + 4, or hundreds, tens, and units components - e.g. 345 = 300 + 40 + 5. (Click here for our 2-digit number partitioning worksheets
and 3-digit number partitioning worksheets
for partitioning practice)
The grid method
enables a complex multiplication to be broken up into a collection of relatively simple multiplications followed by some column addition
Grid Method Example
54 x 12 can be partitioned
to give us (50 + 4) x (10 + 2)
this can be expanded to four simple multiplications which when added together give the final answer: (50 x 10) + (50 x 2) + (10 x 4) + (4 x 2).
This is done with the use of a grid
as shown below:
Total up the columns and write the totals in the row at the bottom of the grid. Then finally add together those totals for the final answer. Here 54 x 12 = 540
The Grid Method can
be used to multiply very large numbers using a larger grid, but by the time a child is confident multiplying 3- and 4- digit numbers using grid multiplication, they are ready for long multiplication which is a faster method.
TU x U Grid Multiplication Worksheets
Here numbers of type TU are multiplied by numbers of type U, for example 17x4
. The child must first partition the TU value and enter the T and U components into the grid together with the U type number by which TU is to be multiplied.
If this number partitioning and/or grid set up causes any problems, try Grid Multiplication TUxU Partitioned
which are worksheets in which the TUxU values have been partitioned and pre-entered in the grid so the child can focus on the multiplications and additions aspects of the grid method.
Next move on to Grid Multiplication TUxTU