A riddle problem is a question or statement intentionally phrased so as to require ingenuity in ascertaining its answer or meaning, typically presented as a game.  Below is a list of the past problem of the week riddles in descending chronological order.

Riddle: What weighs more? A pound of feathers or a pound of stones?
Answer: The same. They both weigh a pound!
Riddle: There is a clothing store in Bartlesville. The owner has devised his own method of pricing items. A vest costs \$20, socks cost \$25, a tie costs \$15 and a blouse costs \$30. Using the method, how much would a pair of underwear cost?
Answer: \$45. The pricing method consists of charging \$5 for each letter required to spell the item.
Riddle: Lily is a lilypad in a small pond. Lilly doubles her size each day, On the 20th day she covers the whole pond. On what day was Lily half the size of the pond?
Answer: Day 19, it's not 10 because on day 20 she doubled from day 19, so 19 must be half the size of the pond.
Riddle: I am four times as old as my daughter. In 20 years time I shall be twice as old as her. How old are we now?
Answer: I am 40 and my daughter is 10.
Riddle: If the day before yesterday is the 23rd, then what is the day after tomorrow?
Riddle: One-fourth of the population of a newly discovered planet has 4 legs while the rest have two legs. There are 60 legs in total. What is the population of the newly discovered planet?
Answer: 4 + 2 + 2 + 2 = 10 legs and 4 inhabitants. Repeat this six times to use up all 60 legs and you end up with 24 total inhabitants.
Riddle: Take two numbers, such that the square of the first, plus the square of the second, shall equal 8; while the first, plus the product of the first and second, shall equal 6. What are the two numbers?
Riddle: If you're 8 feet away from a door and with each move you advance half the distance to the door. How many moves will it take to reach the door?
Answer: Infinity! Technically you will never reach the door, as you can only move half the distance, no matter how small.
Riddle: How much will a 38° angle measure when looked at under a microscope that magnifies ten times?
Answer: It will still be 38°.