Description: Sometimes multiplying really small decimals (with all those zeros!) can be a little intimidating. Watch as we show you a handy trick to simplify these problems and solve them. Created by Sal Khan. Let's multiply 1.21, or 1 and 21 hundredths, times 43 thousandths, or 0.043. So let's just think about a very similar problem but one where essentially we don't write the decimals. Let's just think about multiplying 121 times 43, which we know how to do.*Teacher Advisor is 100% free.