By David Pleacher
Question: Does a pound of gold or a pound of feathers weight more?
Answer: The feathers. A pound of feathers is measured in avoirdupois weight, in which one pound equals 16 ounces. Precious metals are measured in troy weight, in which one pound equals 12 ounces.
However, the ounces are not measured in the same way. In avoirdupois weight, one ounce = 437.5 grains. In troy weight, one ounce = 480 grains.
So, one pound of feathers weighs (16)x(437.5 grains) = 7,000 grains. One pound of gold weighs (12)x(480 grains) = 5,760 grains.
Question: You have two coconuts and you want to find out how high they can be dropped from a 100 story building before they break. But you only have $1.40 and the elevator costs a dime each time you ride it up (it's free for rides down).
How can you drop the coconuts to guarantee you will find the lowest floor they will break at, while starting and ending at floor 1?
Note: They break when dropped from the same height and they don't weaken from getting dropped.
Answer: You could drop it at floor 1 first (because you start at floor 1). Then you would go to the floors: 14, 27, 39, 50, 60, 69, 77, 84, 90, 95, 99, and 100. Whatever floor your first coconut breaks at, go to the floor above the last floor the coconut survived and drop the second coconut from this floor. Then go up by one floor until the second coconut breaks and that is the lowest floor it will break at.
Question: The warden of a circular jail is extremely hyper one day so he begins running around opening cells. The jail has 100 cells numbered from 1 to 100. He runs in a circle and opens all of the cells. Next he runs around and closes every 2nd cell (starting with cell 2, 4, 6 , etc.). If a cell is open he closes it and if a cell is closed he opens it. When he finishes running by all 100 cells he opens/closes every 3rd cell (starting with 3, 6, 9, 12 etc.), then every 4th cell (starting with 4, 8, 12, etc.) and so on. He does this until he goes around and only changes the 100th cell.
When he is done what cells will be open?
Answer: The cells 1, 4, 9, 16, 25, 36, 49, 64, 81, and 100 will be open. Only the cells that have two of the same factors (4 = 2 * 2) will be open because they are opened and closed the same number of times (except 1 which is just opened). Since they have the same factor twice their number of factors is odd.
Question: Why are manholes round instead of square?
Answer: If they are round the manhole covers cannot slip into the hole if the hole is slightly smaller than the cover, but if they are square the hole would have to be about 50 percent of the area of the cover to stop the cover from falling into the hole (diagonally).
Question: A mother is 21 years older than her child. In 6 years the mother will be 5 times older than her baby.
Where is the father?
Answer: He is with the mother.
If you do the math: (baby's age) + 21 + 6 = 5 * (baby's age + 6)
(baby's age) + 27 = 30 + 5 * (baby's age)
-3 = 4 * (baby's age)
-3/4 = baby's age
The baby will be born in 9 months.
Follow us and get the Riddle of the Day, Joke of the Day, and interesting updates.