Answer:
3 1/4
Explanation:
Given that :
Length of piece of wood = 30 1/2
Length of other book shelves = 27 1/4
Difference between the length gives how much longer the piece of wood is than the other book shelves :
30 1/2 - 27 1/4
61 /2 - 109 /4 = (122 - 109) / 4
(122 - 109) / 4 = 13 /4
13 /4 = 3 1/4