Fastest way of SQUARING any number.

Usually we know the square of numbers up to 20 since their squares are frequently used in various mathematics problem. But if we have to square the larger numbers then we have to use calculators or have to multiply tediously if calculator is not allowed. Here I am going to suggest you a simplest and fastest way of squaring as follow:
Let 36 be a number to be squared.
step 1 : Select another number such that addition or subtraction of this number with 36 results the
             nearest multiple of 10.
                here 4 is suitable so 36+4=40   &   36-4=32
step 2 : Then multiply both 40 and 32

                     40*32=1280 ( just multiply 32 by 4 and place '0' at last )
step 3 : Finally square the selected number(here 4) and add to 1280.

                                   1280+16=1296
                  hence square of 36 =1296
                                                 Actually the trick used here is so simple. As follow :