Each week, we post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for two free Manhattan Prep GRE Strategy Guides.

Two stores usually charge the same regular price for identical jars of peanut butter. This week, Store A is offering the jars of peanut butter for 10% less than regular price, and Store B is offering 6 jars of peanut butter for the regular price of 5.  If 6 jars of peanut butter cost a total of $1.18 less at Store B than at Store A this week, what is the regular price of a jar of peanut butter?

See the answer choices and submit your pick over on our Challenge Problem page.