Digit Dilemmas. Puzzle tester Nick Baxter found the best answer to problem 4. Several readers thought they had found other answers to the last problem, but had missed the transition from the last digit back to the first.

When One Plus One Doesn't Equal Two. Inspired by a wonderful note in Dmitri Borgmann's book Beyond Language where he lists for each number one through twelve a language in which the name for that number that has that number of letters. For instance five is CINCO in Spanish. Borgmann also noted that FIVE contains the Roman numeral IV and SIX contains IX.
     Many readers found alternate answers for the last problem, which asks for a number that is written with that number of straight lines. Since I don't say how the letters are drawn, there are many plausible answers, such as:

• The answer given was TWENTY NINE, which would be correct, except that, in English, the number 29 is written as twenty-nine--including the hyphen--leaving it with thirty line segments. Another answer would be thirty-three. If you draw the capital R so that it includes four straight lines (forgive the poor e-mail representation), THIRTY contains 15 line segments; THREE contains 17; the hyphen contains 1. The total is 33 line segments. -- Jay Bullock
• If you write the letter S using five straight lines (as in the digital-clock number 5), then the answer TWENTY SIX has 26 segments. --Sandy Howison
  

Cross Purposes. To be thorough, I made a spreadsheet of every possible three digit fraction, looking for ones that worked.