JSFiddle - React, Tailwind, and code Playground

JavaScript

const truncate = function(number, places = 2) {
  let shift = Math.pow(10, places);
  return ((number * shift) | 0) / shift;
};
console.log('in result should been 0.29, but show 0.28');
console.log(truncate((10 * 2.9) / 100));