Q. A while back you had multiplication tricks by 9’s in the Orange County Register. You were nice enough to e-mail me the information after I lost the column. I recently gave the information to my ...

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 ...

Back in primary school when we were learning how to multiply two, multi-digit numbers by hand, our teacher showed us a little trick to verify that we had the correct result calculated. I was impressed ...