Long Multiplication

The numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 are called single-digit numbers (because it only takes one digit to write each of these numbers), but all bigger numbers need two or more digits to write them: 10, 11, 12, 13, 100, 1000 and so on, and they are called multi-digit numbers. Long multiplying is the name for the process of multiplying a multi-digit number by another multi-digit number. Don't be scared by any of these fancy words: there is absolutely nothing new for you to learn other than how to handle the size of these sums. Let's just dive straight in with a nice big example so that you can see the pattern you need to follow when solving them: we're going to multiply a four-digit number by a three-digit number, and we'll tackle it in four stages, one stage for each digit of the three-digit number, plus a fourth stage in which we'll add all the results together to get the final answer:-

   8641
  532
       
      0
     00
       
                                       

to carry out each step.

You can now practise what you have just learned by playing another game (click on this link), though you should also make sure you can do long multiplication sums on paper with a pencil at some point, because that is how you have to do them in exams. Make sure you come back here afterwards, because we haven't quite finsihed yet.

2B ctd... (multiplying decimals)