Answer:
18.5 in
Explanation:
Let x be the length of board.
Actual width of board,b=1.5 in
Height of board,h==5.5 in
Density of wood=0.021lb/cubic in
Weight of wood=3.2 lbs
We know that
Volume=

By using the formula
Volume of wood=

Volume of wood=

Using the formula


Hence, the length of board=18.5 in