Backtracking for Knapsack
<p>I need to do use backtracking to solve a Knapsack problem. This is an example of what I might have to do for my problem. My question is, how do I know the bounds? I understand that the bound for the root node is $115 because it is the sum of all values. But what I don't understand is how the right child of the root has a bound of $82.</p>

<p>I found this text explaining what it means, but I am still confused:</p>

<pre><code>For a maximization problem the bound is an upper bound, 
    – the largest possible solution that can be achieved by 
      expanding the node is less or equal to the upper bound 
</code></pre>

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