Linq Query to Sum into new list : <p>I want to create a 2nd list from 1st list to show the sum with descending order.</p>

<pre><code>1st list :
     ID               Value
    1                  20
    2                  40
    3                  10

2nd List:
 ID               Value
1                  70
2                  50
3                  10
</code></pre>
