With this video you will learn to multiply numbers up to 20X20 in your head!!! Multiply up to 2 numbers, from 11 to 19 without a calculator!! Take the 2 numbers, then: -Place the larger number at the top. -Take the first number and the last digit of the second number. -Add the first number and the last digit of the second number. -Then Multiply the answer by 10 or just add a cero, and keep the answer in your mind. -Then Multiply the two latest digits of the two numbers, take the answer and... -Add the first result with the other and voila!!!! Practice it first!! then you will be able to do it in your mind in just 5 seconds!!!