12 7x3 4 July 8, 2019 16 32 64 128 12 7 x 3 4 7x3 12 4 6 4x 3 x 7 )=- 12 3x 4 x 3 7 12 2 4x 12 7 x 3 21 12 4 3 x 7 7 12 x 4 9 3 7 8 x 3 12 4 4 7 x 3 12 11 12 x 4 15 3 7 12 x 4/7 12 x 3/7
