does u wish to multiply the number for easier.
here is the simple maths tricks
if it is odd number......
number=75 then add 0 @ last so it will become 750 and divide it by 2
then the answer 375
for even number....
just divide the number by two and add 0 @ last
ex:-278 now divide it by two then it will become 136 and 0 at last then the answer is 1360.........