Răspuns :
11 + (11+1) + (11+2) + (11+3) + (11+4) + (11+5) + (11+6) + (11+7) + (11+8)=
11×9 + (1+2+3+...+8) = 99 + 8×9:2 = 99+36 = 135 .
11 + (11+1) + (11+2) + (11+3) + (11+4) + (11+5) + (11+6) + (11+7) + (11+8)=
11×9 + (1+2+3+...+8) = 99 + 8×9:2 = 99+36 = 135 .