SILLY TREES is an anagram of what 10-letter word? What’s the next number in the sequence 483, 759, 264, 837? What two words that sound alike mean AUDIBLY and PERMITTED? Don’t be surprised if the answers aren’t easy to figure out. These puzzles are from a rich and varied new Mensa collection, and they’re meant to challenge even the most experienced puzzle fans. Some of the mind teasers test for knowledge of specific facts, but most can be solved by pure brain power. Readers who don’t give up too soon, who look beyond the obvious, use their imaginations, and put their minds to work, will find a great sense of accomplishment and hours of fascinating diversion. (answers: tirelessly, 592, aloud and allowed.)