32 PEACTICAL MEASUREMENTS 



33. Rule. To find the number of board feet in a piece of 

 lumber, divide by 12 the product of its length in feet by its 

 width and thickness in inches. 



The work may usually be shortened by arranging it in 

 the form for cancellation. Thus, 

 3 4 



34. Rule. To find the cost of a bill of lumber, divide the 

 number of board feet by 100 by pointing off two decimal 

 places, then faultipty by the price per hundred feet. 



EXERCISE 



1. Read the following bill of lumber: 



23 pc. 4" x 6" x 12', 

 7 pc. 4" x 6" x 16', 



15 pc. 2" x 8" x 20', 



16 pc. 2" x 6" x 20'. 



2. Determine the number of board feet of lumber in 



10 pc. 2"x 4" X 12', 



12 pc. 3" x 8" x 16', 



16 pc. 3" x 6" x 18', 



80 pc. 3" x 8" x 20'. 



3. At $1.75 per hundred, find the cost of 



7 pc. 2" x 10" x 18', 

 75 pc. l"x 8"xl4', 

 30pc.2"x 4" X 12'. 



4. Find the cost of the following : 



20 pc. 2" x 4" x 16' at $1.50 per 100, 



60 pc. 1" x 6" x 14' at $1.75 per 100, 



100 pc. 1" x 4" x 12' at $2.25 per 100. 



