Multiply any 2-figure numbers together by mere mental arithmetic!

If you want 21 stamps at 26 pence each you can

easily find the total price in your head.

There were no carries in the method given above.,/p>

However, there only involve one small extra step.

21 x 26 = 546

 

The method is the same as above
except that we get a 2-figure number, 14, in the
middle step, so the 1 is carried over to the left
(4 becomes 5).

So 21 stamps cost £5.46.

Practise a few:

1) 21 x 47

2) 23 x 43

3) 32 x 53

4) 42 x 32

5) 71 x 72