What is your answer?

**Note:** Another difficult problem on the exam was: "Circle X has a radius of π. Circle Y has a circumference of 8π. Circle Z has an area of 9π. List the circles in order from smallest to largest radius." Do you see why almost 40% of the students selected the wrong answer of X, Y, Z?

Source: Adapted from *MAA FOCUS*, February 2007

**Hint:** The problem actually was a multiple choice problem, where 15.39% of the students chose (A) 1, 16.15% chose (B) 2, 26.01% chose (C) 3, 17.68% chose (D) 4, 12.09% chose (E) 9, and 12.55% of the students did not answer the question.

Does this information help?

**Solution Commentary:** It is perhaps easier to turn the problem into a division problem: CDCD/CD = ABA. Now CD "gozinta" CD** how many times...etc.

**A Sidenote:** The perplexity of the problem perhaps is increased by dual roles of letters. For example, B is a digit (actual value is 0)...but also is a choice for an answer (B) 2, etc.