A Cool Math Fact

Peace be upon you, and today's Cool Math fact is 'The 7, 11 13 trick'! This is how you do: Pass a friend a calculator and ask your friend to type in any THREE digit number your friend likes, and then tell your friend to tell you his/her number. Then, as fast he/she can, he/she has to push these buttons (on the calculator you passed to him/her): x7 x11 x13 = You would have already written the answer before he/she was finished! All you do is to write your friends number twice. So if your friend put 451 then the answer is 451,451! Test this out yourself if you don't believe me! Trust me, I did actually try it out and it worked! So try it out yourself now! The reason why this works is that 7x11x13 = 1,001 When you multiply any three digit number by 1,001 , you just get the same number twice. Neat, isn't? If you like this trick, here are a few more. Try them yourself on a calculator and see what they can do! Put in a TWO digit number then push: x3x7x13x37 = Put in a single digit number: x3x37 = Put in a single digit then push: x3x7x11x13x37 = Cool, isn't it? So thank you for reading this first 'Cool Math Fact' and I will see you later, bye!