jquery check a radio input code example
Example 1: jQuery check a radio button
// jQuery version 1.6 or above use:
$("#myRadioID").prop("checked", true);
//jQuery versions below 1.6 use:
$("#myRadioID").attr('checked', 'checked');
Example 2: How can I know which radio button is selected via jQuery
if ($('input[name="radioName"]:checked', '#myForm').length) {
//Yes, it's checked!
}