Jason bought a new bookcase that can hold a maximum of 80 pounds of weight. Jason has 70 hardcover books that each weigh half a pound, 30 textbooks that each weigh 2 pounds, and 3 knick-knacks that each weight 6 pounds. How many pounds over the bookcase's weight limit is this total collection of items?
First find the total weight of the hardcover books: 70 books * .5 pound/book = 
<gadget id="calculator">70*.5</gadget>
<output>35</output>
35 pounds.
Then find the total weight of the textbooks: 30 books * 2 pounds/book = 
<gadget id="calculator">30*2</gadget>
<output>60</output>
60 pounds.
Then find the total weight of the knick-knacks: 3 knick-knacks * 6 pounds/knick-knack = 
<gadget id="calculator">3*6</gadget>
<output>18</output>
18 pounds.
Then find the total weight of all the items: 35 pounds + 60 pounds + 18 pounds = 
<gadget id="calculator">35+60+18</gadget>
<output>113</output>
113 pounds.
Then subtract the bookcase's weight limit: 113 pounds - 80 pounds = 
<gadget id="calculator">113-80</gadget>
<output>33</output>
33 pounds.

<result>33</result>