This rather old-fashioned question was asked on the TIMSS Study.
Juan has 5 fewer hats than Maria, and Clarissa has 3 times as many hats as Juan. If Maria has n hats, which of these represents the number of hats that Clarissa has?
Only 49% of U.S. eighth graders could answer this correct.
Note: Ms. Lindquist tries to use questions that are more real-life then this.