Gayle has a piece of plywood that is twelve feet long. Gayle is using the piece of plywood to saw off pieces of wood needed to build shelves in her room. First, Gayle saws off 3/10 of the wood. Next, Gayle saws off 6/10 of the wood. Last, Gayle saws off 2/10 of the board. Gavin says she has 2/10 of the wood left to use for another shelf. Is Gayle correct? Show all your mathematical thinking