<prompt> Acha x_1, x_2, lddots, x_n ziwe nambari halisi zinazokidhi x_i 1 for i 1, 2, dots, n, na x_1 x_2 vitone x_n 19 x_1 x_2 vitone x_n.Ni thamani gani ndogo zaidi iwezekanayo ya n?  <response>: Upande wa kushoto unatosheleza x_1 x_2 vitone x_n 1 1 dots 1 n, huku upande wa kulia ukitosheleza 19 x_1 x_2 dots x_n ge 19.Kwa hivyo, n 19, hivyo n ge 20. Inawezekana kwamba n20, kwani, kwa mfano, tunaweza kuchagua beginaligned x_1 x_2 vitone x_10 tfrac1920, x_11 x_12 dots x_20 -tfrac1920, mwishoimepangiliwaambayo hufanya x_1 x_2 vitone x_20 19 na x_1 x_2 vitone x_20 0. Kwa hiyo jibu ni 20. 