Written Multiplication of Three-Digit Numbers by One-Digit

Written multiplication can be done step-by-step by setting out the calculation carefully and remembering to regroup if necessary.

 

Example

Work out

947 × 7

 

Answer

1. Rewrite the calculation vertically, like this:

2. Then multiply the numbers in the ones column together, so 7 × 7 = 49. 

Write the 9 in the ones column and regroup the 4 tens below in the tens column.

 

3. Next multiply the numbers in the tens column together, so 4 × 7 = 28 and add the 4 tens that were regrouped.

 

This gives us 28 + 4 = 32 , so we write the 2 in the tens column and regroup the 3 hundreds below in the hundreds column.

 

4. Lastly, multiply the numbers in the hundreds column, so 9 × 7 = 63 and add the 3 that was regrouped.

This gives us 63 + 3 = 66 in the thousands.

 

So, in full, we have:

 

So      947 × 7 = 6629