A book has 280 pages. Xiaohong reads (1/7) on the first day and the rest (1/2) on the second day. How many pages should she start reading on the third day?
一本书有280页，小红第一天看了(1/7)，第二天看了剩下的(1/2)，第三天应该从第多少页开始看．
<result>161</result>