Hacks World demonstrated a simple technique for multiplying quickly using the fingers. The technique works for multiplying numbers by six, seven, eight, nine, or 10, and can be a useful tool for anyone learning to multiply.
Being able to multiple with your fingers is a valuable skill to have, and people have been doing it since at least the 15th century. We may have cellphone calculators, but in many cases it is actually easier to keep your phone in your pocket and multiply with your fingers. It is also helpful for students learning multiplication for the first time. For finger multiplication to work successfully, you must first know your multiplication tables from one to five. Multiplying by hand works for the tables of six, seven, eight, nine and ten.