Written multiplication can be done step-by-step by setting out the calculation carefully and remembering to carry if necessary.
Example
Work out
78 × 7
Answer
Set out the calculation like this:
Then multiply the units together, so 8 × 7 = 56.
Remember to carry the 5 tens below the next column.
Then multiply the tens, so 7 × 7 = 49 and add the 5 that was carried.
This gives us 49 + 5 = 54 going into the hundreds column.
So 78 × 7 = 546