What are you like at multiplications? Chances are if you're a mere mortal 2, 5s and 10s won't seem too taxing. But when it comes to figuring out what 42x21 is, you may wish somebody had shown you the ...

Anita Ponsaing receives funding from the ARC Centre of Excellence for Mathematical & Statistical Frontiers (ACEMS). Most people will probably remember the times tables from primary school quizzes.

Swapping numbers for lines can make the hardest mental arithmetic seem easy peasy and this is how to do it What are you like at multiplications? Chances are if you're a mere mortal 2, 5s and 10s won't ...

Let's draw! Now the fun bit. The drawing. For every number, you draw the corresponding number of lines on a piece of paper or a whiteboard. Begin with the first number in the sum which here is 13.