Solution 1 :

You can access the value of the number input using e.target.value.

Here’s an example:

$(function(){
  $('input[type=radio]').on('click',function(){
    data= $(this).data('price');
    $('#result').val(data);
    $('#result2').text(data*3);
   
  });
  
  $('#result').on("change", function(e) {
    data= e.target.value;
    $('#result').val(data);
    $('#result2').text(data*3);
  })
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="radio" name="highlight" data-price="1" value="a1">a1
    <input type="radio" name="highlight" data-price="2" value="a2">a2
    <input type="radio" name="highlight" data-price="3" value="a3">a3
    <input type="radio" name="highlight" data-price="4" value="a4">a4

    <input type="number" id='result'>
    <div id='result2'></div>

Solution 2 :

$(function(){
  $('input[type=radio]').on('click',function(){
    data= $(this).data('price');
    $('#result').val(data);
    $('#result2').text(data*3);
   
  });
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form  id="my_form" class="container" oninput="result2.value = parseInt(result.value*3)">
    <input type="radio" name="highlight" data-price="1" value="a1">a1
    <input type="radio" name="highlight" data-price="2" value="a2">a2
    <input type="radio" name="highlight" data-price="3" value="a3">a3
    <input type="radio" name="highlight" data-price="4" value="a4">a4

    <input type="number" id='result'>
    <input type="number" id='result2'>
</form>

I simply add oninput function

Problem :

I want to do a live calculation, Where output will be printed from the input filed. I have to put data to that specific input field by selected radio button or , manually typing. I have done the live calculation when that input field data was selected from the radio button, But the problem creates when I type manually to the input field. How can I do live calculation both on typing or selecting values?

$(function(){
  $('input[type=radio]').on('click',function(){
    data= $(this).data('price');
    $('#result').val(data);
    $('#result2').text(data*3);
   
  });
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="radio" name="highlight" data-price="1" value="a1">a1
    <input type="radio" name="highlight" data-price="2" value="a2">a2
    <input type="radio" name="highlight" data-price="3" value="a3">a3
    <input type="radio" name="highlight" data-price="4" value="a4">a4

    <input type="number" id='result'>
    <div id='result2'></div>