(1-1/15)+(1-1/35)+(1-1/63)+(1-1/99)+(1-1/143)+(1-1/195)+(1-1/255)+(1-1/233)
=8-(1/15+1/35+1/63+1/99+1/143+1/195+1/255+1/233)
=8-0.5(1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11+1/11-1/13+1/13-1/15+1/15-1/17+1/17-1/19)
=8-0.5(1/3-1/19)
=8-8/57
=448/57
(1-1/15)+(1-1/35)+(1-1/63)+(1-1/99)+(1-1/143)+(1-1/195)+(1-1/255)+(1-1/233)
=8-(1/15+1/35+1/63+1/99+1/143+1/195+1/255+1/233)
=8-0.5(1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11+1/11-1/13+1/13-1/15+1/15-1/17+1/17-1/19)
=8-0.5(1/3-1/19)
=8-8/57
=448/57