At lumber company, shelves are sold 3 types of wood, 2 different widths and 5 different lengths.

Ok this will involve multiplication, So since a lumber company shelves are sold in 3 types of wood and 2 different widths and 5 different lengths you will multiply 3 and 2 and 5 and your answer will be 30.

3x (5x2) = 10

10x3=30

So are you trying to find the number of different possible shelves? If yes then he answer is 30 because 2*3*5=30