Sep 15

Puzzle at the End of the Book

“Puzzle at the End of the Book” is a very challenging puzzle from the 2017 MIT mystery hunt. The answer to this puzzle is a 6-letter word, related to a woman’s beauty. The solution is intricate and requires careful analysis of the book, some geeky references, and possibly a good amount of Google searching. Use the hints below if you need help with solving puzzle.

Source: MIT

Pay attention to the words in green. They form a riddle which needs to be answered.

Pay attention to the broken lines along the bubble speeches. Use an appropriate code to decode them.

Pay attention to the ship, the brick wall, the ladder, and the bucket. Use an appropriate code to decode them.

Pay attention to Grover’s arms. Use an appropriate code to decode them.

Pay attention to the fonts used for typing the words in red. Use their first letters to form a word.

Pay attention to the unusual words appearing in the text. Use parts of these words, combined with immediately preceding/succeeding parts of neighboring words, to get the names of six Pokemons. Use their first letters to form a word.

The names of the six muppets have the same lengths as the six words discovered from the previous steps. See which letters overlap if you compare each muppet name with its corresponding word. Arrange these letters to get the final answer.

The answer to this puzzle is MAKEUP.

In order to get to it, first you must find 6 secret fantasy related words.

1. The green words on the pages of the book form the sentence Wooden ship turned around before understanding sea monster (SIX). “Wooden ship” = ARK, “turned around” -> KRA, “understanding” = KEN, so we get KRAKEN, which is a sea monster with six letters.

2. The broken lines along the speech bubbles can be decoded using Morse code to spell Lilith, Morrigan, Scarlet, or Queen of Pain. These female demons give the secret word SUCCUBUS.

3. The ship, the brick wall, the ladder, and the bucket contain four hidden Brail letters, which spell out the word HUMA.

4. Grover’s arms encode through semaphore the Inuit mythological creature QALUPALIK.

5. The word “Puzzle” is written in five different fonts – Times New Roman, Impact, Twentieth Century, Arial, Nosifer. The first letters of these fonts form the word TITAN.

6. Each page from 2 to 8 contains some unusual words. Part of these words, combined with immediately preceding/succeeding parts of neighboring ones, give the six Pokemons Sandshrew, Pinsir, Ekans, Clefairy, Tentacruel, Eevee, Rapidash. Their first letters form the secret word SPECTER.

The names of the six muppets on the last page are Barkley, Donmusic, Elmo, Kermit, Misspigy, Oscar. They perfectly match in terms of length with the six secret words which we found above. Also, each pair of name with secret word overlap in just one position, the six resulting letters are E, U, M, K, P, A. If we arrange these letters with respect to the length of their corresponding words, we get the final answer MAKEUP.

Sep 13

Eight Queens Puzzle

Rearrange the eight queens so that no two of them attack each other. For an extra challenge, make sure that no three of them lie on a straight line.

The original puzzle has 10 unique solutions, up to rotation and symmetry. With the additional restriction imposed, there is only one solution.

Sep 11

Batting Averages

David Justice and Derek Jeter were professional baseball players. In 1997 they had the following conversation:

David: Did you know that in both 1995 and 1996 I had better batting averages than you?

Derek: No way, my batting average over the last two years was definitely higher than yours!

It turned out that both of them were right. How is it possible?

This is the so called Simpson’s paradox. The reason it occurred is that during 1996 both players had high averages and Derek Jeter had many more hits than David Justice. In 1996 both players had low averages and David Justice had many more hits than Derek Jeter. You can see their official statistics below.

 Player 1995 1996 1995-1996 Derek Jeter 12/48 (.250) 183/582 (.314) 195/630 (.310) David Justice 104/411 (.253) 45/140 (.321) 149/551 (.270)
Sep 9

Thoka’s Rebus 1

Can you figure out which word is depicted by this rebus?

Each of the images in the first row depicts HAIR. Each of the images in the second row (except the second cell) depicts a BUG. Each of the images in the third row depicts ER.

The I from HAIR on the first row gets moved right after the B from BUG on the second row. Also, the U from BUG gets flipped upside down. Therefore, we get HARBINGER.

Sep 7

Green House

There was a green house. Inside the green house there was a white house. Inside the white house there was a red house. Inside the red house there were lots of babies. What is it?

Sep 5

Black Hole Sun

Escape from the black hole to the upper right corner in this maze, created by Ben Uelk.

The solution is shown below.

Sep 3

Larger or Smaller

Alice secretly picks two different integers by an unknown process and puts them in two envelopes. Bob chooses one of the two envelopes randomly (with a fair coin toss) and shows you the number in that envelope. Now you must guess whether the number in the other, closed envelope is larger or smaller than the one you have seen.

Is there a strategy which gives you a better than 50% chance of guessing correctly, no matter what procedure Alice used to pick her numbers?

Choose any strictly decreasing function F on the set of all integers which takes values between 0 and 1. Now, if you see the number X in Bob’s envelope, guess with probability F(X) that this number is smaller. If the two numbers in the envelopes are A and B, then your probability of guessing correctly is equal to:

F(A) * 0.5 + (1 – F(B)) * 0.5 = 0.5 + 0.5 * (F(A) – F(B)) > 50%.