It has been almost 20 years since I published the first math contest workbook in 2002 This workbook is 3-in-1, one-of-a-kind and world's first, I believe. In the past 20 years, I created many workbooks and the reason simply is because I could not find suitable teaching materials to use at my own after-school learning centre. Why I created another workbook this time? It is simply because there is a need for it. Let me explain. I created the following...