Amazing Mathematics Tricks   Multiply of 37 by multiplies of 3:   3 x 37 = 111   6 x 37 = 222   9 x 37 = 333   12 x 37 = 444   15 x 37 = 555   18 x 37 = 666   21 x 37 = 777   24 x 37 = 888   27 x 37 = 999       Trapeze:       1 x 9 + 2 = 11   12 x 9 + 3 = 111   123 x 9 + 4 = 1111   1234 x 9 + 5 = 11111   12345 x 9 + 6 = 111111   123456 x 9 + 7 = 1111111   1234567 x 9 + 8 = 11111111   12345678 x 9 + 9 = 111111111         Another Trapeze:   1 x 8 + 1 = 9   12 x 8 + 2 = 98   123 x 8 + 3 = 987   1234 x 8 + 4 = 9876   12345 x 8 + 5 = 98765   123456 x 8 + 6 = 987654   1234567 x 8 + 7 = 9876543   12345678 x 8 + 8 = 98765432   123456789 x 8 + 9 = 987654321     And another one:       0 x 9 + 8 = 8   9 x 9 + 7 = 88   98 x 9 + 6 = 888   987 x 9 + 5 = 8888   9876 x 9 + 4 = 88888   98765 x 9 + 3 = 888888   987654 x 9 + 2 = 8888888   9876543 x 9 + 1 = 88888888   98765432 x 9 + 0 = 888888888   987654321 x 9 - 1 = 8888888888   9876543210 x 9 - 2 = 88888888888       Nice one:   And finally, take a look at this symmetry:   1 x 1 = 1   11 x 11 = 121   111 x 111 = 12321   1111 x 1111 = 1234321   11111 x 11111 = 123454321   111111 x 111111 = 12345654321   1111111 x 1111111 = 1234567654321   11111111 x 11111111 = 123456787654321   111111111 x 111111111 = 12345678987654321 111.111.111 x 111.111.111 = 12.345.678.987.654.321  This math trick will determine your birthday. Just follow the steps with a calculator and press equal after each step. Go ahead and try the trick without cheating! For a simple, online JavaScript calculator, click on the calculator button. Add 18 to your birth month Multiply by 25 Subtract 333 Multiply by 8 Subtract 554 Divide by 2 Add your birth date Multiply by 5 Add 692 Multiply by 20 Add only the last two digits of your birth year Subtract 32940 to get your birthday!