The phrase gives you an interval where the extremes are included.
The intervals may be indicated in several ways. 
 7.2 ≤ x ≤ 7.6
        
             
        
        
        
Step-by-step explanation:
Given that,
- Length of the one portion of the board = x feet
- Length of the another portion = (7x – 9) feet
According to the question,
 Total length = Sum of the length of the two pieces
 Total length = Sum of the length of the two pieces
 Total length = {x + (7x – 9)} feet
 Total length = {x + (7x – 9)} feet
 Total length = {x + 7x – 9} feet
 Total length = {x + 7x – 9} feet
 <u>Total length = (8x – 9) feet</u>
 <u>Total length = (8x – 9) feet</u>
Therefore, the total length of the board as a simplified expression in x is (8x – 9) feet.
 
        
             
        
        
        
2/3 ÷ 4 = 2/3 * 1/4 = 2/12 = 1/6