At a math convention, nine out of eleven people are bored by cable news. If there are 122 people at the convention who are not bored by cable news, then how many people at the convention are bored by cable news?
2/11 are not bored....so..
The total number of people at the convention =122 /(2/11) = 671
Number bored = 671 ( 9 / 11 ) = 549