JSFiddle - React, Tailwind, and code Playground
HTML
<div>Количество работников на точке:</div>
<label><input type="radio" name="count" value="1">1</label>
<label><input type="radio" name="count" value="2">2</label>
<label>Кепки: <input type="number" name="kepka" value="0"></label>
<label>Стаканы: <input type="number" name="stakan" value="0"></label>
<label><input type="button" value="=" onClick="check();"><input type="text" id="result" disabled></label>
CSS
label{
display:block;
}
JavaScript
function check()
{
var count = document.querySelector('input[name="count"]:checked');
if(count === null) count = 1;
else count = count.value;
var kepka = document.querySelector('input[name="kepka"]');
if(kepka.value === '') kepka = 0;
else kepka = kepka.value;
var stakan = document.querySelector('input[name="stakan"]');
if(stakan.value === '') stakan = 0;
else stakan = stakan.value;
var result = document.getElementById('result');
result.value = ((kepka * 20) + (stakan * 10)) / count*1
}