4 9 x 3 20 July 8, 2019 16 32 64 128 4 9 x 3 20 simplified X 4 9x 3 20x 2 9 x 3 20 18 x 4 8 1 2 x 9 3 4 200 pages 4 27 x 3 88 x 9 20 51 3 4 3 x 9 20 4 5 0 9 x 3 1 2 x 20 4 5 4 3 x 9 20 3 x 3 = 9 3 4 x 9