title: question regarding index errors and division
body: <p>I have two lists and I wanted to create generate the quotients using a for loop. Specifically, I would want to have .5 and .25 and .125 and in that order. Of course, I could just take these values and determine the quotients manually, but I am looking at this from the perspective of someone who is taking their first stab at learning Python. I have read some other articles on for loops, but do not see why the below produces :  index error: list index out of range. Thus, I am looking not only for the modification of this code but also a reasonable explanation as to why there is such an error.</p>
  
  <pre><code>x=[2,4,16]
  y=[4,16,128]
  for i in y:
      y[i]/x
  </code></pre>