5 6 x 1 20 July 8, 2019 16 32 64 128 4 2 5 6 10 x 1 3 20 5 x 1 )+ 4 6 x 2 )- 20 5 6 1 3 1 2 x 20 6 x 1 )- 5 x 2 )= 20 5 6 x 1 2