Definition
Short multiplication
Short multiplication is a written method for multiplying a multi-digit number by one digit.
Continue from this idea into connected AXIO math.
Defining relationship
One row and one-digit multiplier: multiply each place, then pass regrouped value left.
Short multiplication is a formal written method for multiplying a multi-digit number by a one-digit number, working place by place and regrouping when a product crosses a place-value boundary.
The regrouped 1 is added in the next place; it is not another multiplier.
What it means
Write the one-digit multiplier under the ones place. Multiply from right to left. When a product has more than one digit, write the digit for the current place and regroup the remaining value into the next place to the left.
Remember it
One row and one-digit multiplier: multiply each place, then pass regrouped value left.
Example
For 326 × 4: 6 × 4 = 24, so write 4 ones and regroup 2 tens. Then 2 tens × 4, plus the regrouped 2 tens, makes 10 tens: write 0 tens and regroup 1 hundred. Finally, 3 hundreds × 4, plus 1 hundred, makes 13 hundreds. The product is 1,304.
Watch for
This sense uses a one-digit multiplier. Multiplying by a two-digit number usually needs long multiplication or another method.
Common mix-up
A regrouped value is added into the next place-value product; it is not treated as another multiplier.
Exact meaning
Short multiplication is a formal written method for multiplying a multi-digit number by a one-digit number, working place by place and regrouping when a product crosses a place-value boundary.