JSFiddle - React, Tailwind, and code Playground

JavaScript

var R = 0.87, N = 4000000;

var RxN = 0;
for(var i=0; i<N; i++) RxN += R;

alert(RxN - R*N);

// We are using doubles (64-bits precission),
// so you would expect Zero
// or 1e-1000 ....

// but it is 0.0003 !!!