The board A is 8 inches. If you use 3/4 of an 8-foot-board. Then you're left with 2 feet. 3 6 -- = -- 4 8 8 - 6 =2 (8= the length of the board) 1/3 of 2 feet = 8 inches 1 24 24 -- x -- = --- = 8 inches 3 1 3 (24= the equal amount of inches in a 2-foot-board)