On-air challenge: The phrases "peace of mind" and "state of mind" differ only in their first words. Their ends, "of mind," are the same. Here are the first words of other familiar pairs of three-word phrases that have "of" in the middle and the same words at the end. Find the final word in the phrase.
For example: Peace and state --> mind.
Last week's challenge: Name a famous Olympics champion past or present — first and last names. Remove every letter from the name that appears exactly twice. The remaining letters in order will name certain minerals. Who is this Olympics star?
Answer: Michael Phelps --> micas.
Winner: Scott Pearl of Wenatchee, Wash.
Next week's challenge, from listener Kenneth Low of Monterey Park, Calif.: Take the name of a country. Among its letters is the name of part of the human body, reading from left to right, although not necessarily consecutively. Cross out these letters. The remaining letters in order, reading left to right, will name part of an animal's body. What country is it?
If you know the answer to next week's challenge, submit it here. Listeners who submit correct answers win a chance to play the on-air puzzle. Important: Include a phone number where we can reach you Thursday, Aug. 18, at 3 p.m. ET.