Question

suma nr 8+9+10+...+50

Answer 1

folosind formula lui Gauss

8+9+10+...+50 = (1+2+3+...+50) - (1+2+3+...+7)= (50*51/2) - (7*8/2) =

= (2550/2) - (56/2) = 1275-28 = 1247 ;