You are shrunk to the height of a nickel and thrown into a blender. Your mass is reduced so that your density is the same as usual. The blades start moving in 60 seconds. What do you do?
Answer: Lie down under the blades.
What’s the next number in this sequence: 10, 9, 60, 90, 70, 66 … ?
Answer: Spell the numbers out.
They are in ascending order, based on the number of letters in the spelled-out numbers. A correct response will have nine letters: 96, for instance. A cleverer answer is “one googol.” That’s the huge number that can be written as a “1” with a hundred zeros after it. Google, the company’s name, was originally a misspelling of “googol.”
Using only a four-minute hourglass and a seven-minute hourglass, measure exactly nine minutes—without the process taking longer than nine minutes.
Answer: A. Start both hourglasses at 0 minutes. Flip over the four-minute glass when it runs out (at 4:00); ditto for the seven-minute glass (at 7:00). When the four-minute glass runs out the second time (at 8:00), the seven-minute glass will then have one minute of sand in its lower bulb. Flip the seven-minute glass over again and let the minute of sand run back. When the last grain falls, that will be nine minutes.
A book has N pages, numbered the usual way, from 1 to N. The total number of digits in the page numbers is 1,095. How many pages does the book have?
Answer: Every page number has a digit in the units column. With N pages, that’s N digits right there. All but the first 9 pages have a digit in the tens column. That’s N – 9 more digits.
All but the first 99 pages have a digit in the hundreds column (accounting for N – 99 more digits).
I could go on, but not many books have more than 999 pages. A book with 1,095 digits in its page numbers won’t, anyway.
This means that 1,095 must equal:
N + (N – 9) + (N – 99).
This can be simplified to:
1,095 = 3N – 108.
That means that 3N = 1,203, or N = 401. That’s the answer, 401 pages.
A man pushed his car to a hotel and lost his fortune. What happened?
Answer: He just landed on Boardwalk in Monopoly.
Thanks to the Wall Street Journal for the answers.