<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<tr id="" class="cart-item-pr">
<td class="weight">
<input type="radio" class="rchecking" id="c2" name="price-hours" value="100" /><label for="c2"></label>
<input type="radio" class="rchecking" id="c3" name="price-hours" value="200" /><label for="c3"></label>
<input type="radio" class="rchecking" id="c4" name="price-hours" value="300" /><label for="c4"></label>
<input type="radio" class="rchecking" id="c5" name="price-hours" value="400" /><label for="c5"></label>
</td>
<td class="price">
<span id="price">200</span>
</td>
</tr>
<script>
document.querySelector('.rchecking[value="'+document.querySelector("#price").textContent+'"]').checked = true;
</script>
</body>
</html>