Răspuns:
(1+2+3+............+2017):2017=(1+2017)·2017:2:2017 = 2017·1009:2017 = 1009
( 1 + 2 + 3 + ... + 2017 ) : 2017 =
( 2017 × 2018 : 2 ) : 2017 =
( 4070306 : 2 ) : 2017 =
2035153 : 2017 = 1009
