title: How to use lambda to insert a value that is two other values within the list added together
body: <p>Here is my code so far:</p>
  
  <pre><code># Defining the results
  Results =[["Harry",20,25],["Sandra",10,12],["Michelle",23,21],["Mike",18,16]]
  
  #Adding the two test scores and appending them onto each persons list
  Results.insert(lambda [x][3],Results[x][1] + Results[x][2])
  
  #Printing the result to check the insert worked
  print(Results)
  #
  </code></pre>
  
  <p>I want to combine each of the users two test results located in index 1 and 2 to create a combined result at index 3, which is at the end of each users own list.</p>
  
  <p>I have tryed using the .insert() function as well as the lambda function to do this. But it says there is an error in line five (where the arrow is below) with an invalid syntax and I'm unsure how to complete this using the lambda thing. I tried using the .append() function but that did not work either.</p>
  
  <pre><code>                      ↓
  Results.insert(lambda [x][3],result[x][1] + result[x][2])
  </code></pre>