การบ้านเรื่องเซต

In a survey of 60 people, it was found that 25 read Newsweek magazine, 26 read time, and 26 read Fortune, Also 9 read both Newsweek and Fortune , 11raed both Newsweek and Time, 8read time and Fortune , and 8read nomagazine at all.
Find the number of people who read all three magazies