Looking at 67 x 23, the three stages would be:
1. multiply 67 by 20. The easiest way to do this is to place a zero in the units column of the answer and then multiply by 2. Placing the zero has the effect of moving each digit one place to the left, hence ten times bigger.
2. multiply by the units (3) and place the answer below, making sure the units go in the units column etc.
3. add the two products.
Of course the units could be multiplied first, followed by the tens, but it is important to find one standard method and stick to it. Of course, tables to to be known to make this a quick process.
This worksheet, and others, similar can be found in the Four Rules section of the site, under Multiplication.
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