Ответы и объяснения

2013-02-14T21:44:21+04:00
Sn= b1(1-q)^1-n /1-q S3=b1(1-1/2)^2/1-1/2 => 28=b1*(1-1/2)^2/1-1/2 => b1=28*1/2/0,25=56 S7=b1(1-q)^6/1-q =>S7=56(1-1/2)^6/1-1/2=0,175