3 7-4x 15 July 8, 2019 16 32 64 128 3 4x 7 15 7 4x 3 )- 15 482 3 4x 7 15 14x 3 4x 7 ≥ 15 2x 3 7 4x 1 15 4x 7 15x 3 2x 5 3 and 4x 7 15 4x 7 x 3 15 3 7-4х 15 5 x 7 = 35
