Za realne brojeve x1,x2,…,x30x_1, x_2, \ldots, x_{30}x1,x2,…,x30 vrijedi
203x1+213x2+⋯+493x30=13,20^3 x_1 + 21^3 x_2 + \cdots + 49^3 x_{30} = 13,203x1+213x2+⋯+493x30=13,
213x1+223x2+⋯+503x30=1,21^3 x_1 + 22^3 x_2 + \cdots + 50^3 x_{30} = 1,213x1+223x2+⋯+503x30=1,
223x1+233x2+⋯+513x30=19.22^3 x_1 + 23^3 x_2 + \cdots + 51^3 x_{30} = 19.223x1+233x2+⋯+513x30=19.
Koliko iznosi 21x1+22x2+⋯+50x3021x_1 + 22x_2 + \cdots + 50x_{30}21x1+22x2+⋯+50x30?