2+4+6+8…+96+98+100 =(2+100)+(4+98)+(6+96)+...(50+52) =25*102 =2550
51+53+55+……+99 =(51+99)*25/2 =1875
1/2+3/4+7/8+15/16+31/32+63/64+127/128+255/256
=(1-1/2)+(1-1/4)+(1-1/8)+(1-...
2+4+6+8…+96+98+100 =(2+100)+(4+98)+(6+96)+...(50+52) =25*102 =2550
51+53+55+……+99 =(51+99)*25/2 =1875
1/2+3/4+7/8+15/16+31/32+63/64+127/128+255/256
=(1-1/2)+(1-1/4)+(1-1/8)+(1-...