Modular arithmetic is fundamental to cryptography. In this system, you can only have integers. For

example, in mod $14$ system, the answer MUST be $0,1,2,3,..\mathrm{.}9,11,12,13.$ Non$-$integer values have no place

in this arithmetic. If you have an answer which is a floating point, such as $12\mathrm{.}5,$ then you are doing

something wrong.