NOTE: Newest BTs in red, Bonuses in blue, comments in green, updates in purple.
- (An old classic!) Your unorganized sock drawer contains 18 white socks and 18 blue socks. How many times do you need to reach inside the drawer and take out a sock at random to guarantee you have a sock of each color?
- A cowboy rode into town on Friday. He stayed in town for three days and rode back out on Friday. How is this possible?
- A palindrome is a number that reads the same forwards and backwards (like 202 or 454). How many palindromes are there between 100 & 1000?
- (A future hypothetical twist to a BT from last time) The 52nd and 54th Presidents of the US have the same mother and father, but are not brothers and are not the same man. How can this be?
- A woman was in her hotel room when there was a knock on the door. When she opened the door slightly, there was a man she’d never seen before. He said, “I’m sorry, I have made a mistake, I thought this was my room” and walked away. The woman went back into her room and phoned security. Why was the woman so suspicious?
- a) How many ways are there to re-arrange the letters in the word ‘STOP’ ? b) How many of those form a common-usage word?
- Augustus De Morgan was a mathematician who lived in the 19th century. He once wrote, I was x years old in the year x2. a) How old was he when he said that? B) What was his birth year?
- Several years ago, I drove a nail into a tree exactly five feet above the ground. The tree grows at the rate of one half-foot a year. Eleven years later, I returned to the tree. How far above the ground was the nail?
- A man wanted to encrypt his password but he needed to do it in a way so that he could remember it. He had to use seven characters consisting of letters and numbers only (no symbols like ! or <). In order to remember it, he wrote down “You force heaven to be empty.” What is his password?
- Guess the next three letters in the sequence: GTNTL.
- (Repeat) A digital clock forms palindromic times 114 times each day. What is A) the least, and B) the most amount of time between two palindromic clock numbers?
BONUS1: There are three light switches outside of a room: #1, #2, and #3- They are connected to three light bulbs inside the room. The door to the room is closed and you can’t see in. All three switches are currently off. You need to figure out which switch belongs to which bulb. You can use the switches however you want to, but can only enter the room once. How do you do it?
BONUS 2: The Jan/Feb BTs mention Year Product Days (For reminder, see Item 4 of this link.) Are there any YPDs in each century with seven (7) or more YPDs?
BONUS 3: A golf ball falls randomly onto a circular green 10 meters in radius, with the cup at the center. What is the probability that the ball is within 1 meter of the cup?
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