My head and tail both equal are, My middle slender as a bee. Whether I stand on head or heel Is quite the same to you or me. But if my head should be cut off, The matter's true, though passing strange Directly I to nothing change. What Am I?
The head of a whale is six feet long; his tail is as long as his head and half his body, and his body is half of his whole length. How long is the whale?
10.
Why? Take the first letter of each spelled out number:
One+Nine+Eight = ONE
Two+Eight+Nine = TEN
The Lazy Brother-in-law
Riddle:
David was known as being lazy. He agreed to work on a job for his brother-in-law for thirty hours at eight dollars an hour, on the condition that he would forfeit ten dollars per hour for every hour that he idled. At the end of the thirty hours David wasn't owed any money and didn't owe his brother-in-law any money either. How many hours did Larry work and how many hours did he idle?
Lazy David worked 16-2/3 hours and idled 13-1/3 hours. 16 and 2/3 hours, at $8.00 an hour amounts to the same amount as 13 and 1/3 hours at $10.00 per hour.
The key to this riddle is realizing that you do not have to pull the emergency switch in the first room, the entrance, and so that room will not lock down. You can leave it, and then return to it and go out the other door. And indeed this is exactly what you need to do so you can hit all 16 rooms and end in the exit room.
Once you know to leave and reenter the first room, there are eight possible solutions to travel through all the rooms and end at the exit. Because the first room is clear, you can backtrack through it to get back on the right track and pull the emergency switch in every room, saving the world from agonizing death by ancient virus.