Many high school teachers will actually admit that you will never use the things they are required to teach you. I found two examples of math applied to everyday life. one useful(ish) and one not so much.

the first: Geek Logik, a book and a blog to promote it. on the blog he gives the equation for weather you should get married or not. I’m sure Randall Munroe would be interested (refer to comic 55), he also has a “will my marriage last.” interesting but i’m not sure if life altering decisions should be made based upon the findings

Will My Marriage Last
Will My Marriage Last

 

Should i get Married?
Should we get married

 

And finally a bit about the potential for useless mathematics. The Daily News gossip column has a bit about Useless Celebrities