Bill gets a flat-screen TV that measures 48 inches by 100 inches. His brother Bob gets a TV that measures 70 inches by 60 inches. If the TVs weigh 4 oz per square inch of screen space, how much more does the heavier TV weigh in pounds? (There are 16 ounces per pound).
First find the screen area of Bill's TV: 48 inches * 100 inches = 
<gadget id="calculator">48*100</gadget>
<output>4_800</output>
4800 square inches.
Then find the screen area of Bob's TV: 70 inches * 60 inches = 
<gadget id="calculator">70*60</gadget>
<output>4_200</output>
4200 square inches.
Then subtract the size of the smaller TV from the size of the bigger TV to find the size difference: 4800 square inches - 4200 square inches = 
<gadget id="calculator">4800-4200</gadget>
<output>600</output>
600 square inches.
Then multiply the size difference by the weight per square inch to find the weight difference: 600 square inches * 4 oz/square inch = 
<gadget id="calculator">600*4</gadget>
<output>2_400</output>
2400 oz.
Then divide the weight difference in ounces by the number of ounces per pound to find the weight difference in pounds: 2400 oz / 16 oz/pound = 
<gadget id="calculator">2400/16</gadget>
<output>150</output>
150 pounds.

<result>150</result>