why function is don't working

Question

https://code.sololearn.com/Wdb7U3d6w2k1/?ref=app

Answer 1

On the button, change it to onclick instead of onchange. Also, look at how I changed your function in order to figure out which radio button is selected. That should do the trick for you.

https://code.sololearn.com/WzK6okZ0Ye4X/#html

<input type="radio" name="ch" value="1">0-10
<input type="radio" name="ch" value="2">11-20
<input type="radio" name="ch" value="3">21-31
<button onclick="chg();">узнай</button>

<script>
function chg()
{
var g = document.querySelector('input[name = "ch"]:checked').value;
alert('проездной на ' + g + 'декаду');
}
</script>

Answer 2

You're welcome.

Answer 3

thanks Netkos