MAGIC IN MATHEMATICS

Here is an interesting trick you can show your friends. First take a sheet of paper and write on it the magic number 12 345 679. It is easy to remember this number because there are all the figures from 1 to 9; only number 8 is not there. Now ask your friend to tell you this favorite figure which he tells you by 9 in your mind. Write the answer under the magic number. For example, if he tells you that his favorite number is 3, you write 27 under the magic number. Then ask your friend to multiply 12 345 679 by 27. The answer will surprise him because there will be only 3-s in it- it is his favorite figure. Th