Funnel Technique

Funnel Technique

Writing a Math Problem on a Stud

Drawing with a carpenter’s pencil, on a stud or dry wall, is a quick and dirty way to figure out a trades math problem, like the perimeter of a room.  But an “are you Smarter than a Fifth Grader” question is either right or wrong.  You add up the sides wrong, and you’ll have the wrong amount of material to get the job done, and, more importantly, you’re wasting time.  There is a technique to adding up multiple sides to help make sure your answer is error free.  It’s called the “funnel technique.”  Consider how to figure out the perimeter of the shape below.


The best way to add up a bunch of feet and inches is to stack them up, and, as illustrated to the right, add a pair of numbers, and then another, until all of the inches, and all of the feet, have been added up to one total number.  Then, apply the “carry” rule we learned in the last lesson to simplify the final answer.  In this problem, 24 inches, or 2 feet, can be carried from the inches column into the feet column.

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