S = 79 + 82 + 85 + 88 + ..... + 184
→ aflu cati termeni are suma cu ratia = 3 ( 82 - 79 = 3; 85 - 82 = 3 )
( 184 - 79 ) : 3 + 1 = 105 : 3 + 1 = 35 + 1 = 36 termeni are suma
→ aplic formula sumei lui Gauss
S = 36 × ( 79 + 184 ) : 2
S = 18 × 263
S = 4 734