JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" name="vvod" id="chislo" /><label>Введите<label>
<input type="hidden" name="koef" class="koef" value="0.5" />
<input type="hidden" name="koef" class="koef" value="0.3" />
<div class="result0"></div>
<div class="result1"></div>

JavaScript

function Chislo(){
var inputChislo = $('input#chislo').val();   
var inputKoef = $('input.koef');
inputKoef.each(function(index) {
var koeff = $(this).val();
var rec = inputChislo * koeff;
$('div.result' + index).html(rec);
//alert (rec);
});
}
$('#chislo').blur(Chislo);