2nd Annual
EFF CryptoChallenge
Contents
Puzzles ........................................................................................................................................................... 3
Easy Level .................................................................................................................................................. 3
Medium Level ........................................................................................................................................... 6
Hard Level ............................................................................................................................................... 11
Hints ............................................................................................................................................................ 17
Easy Level ................................................................................................................................................ 17
Medium Level ......................................................................................................................................... 17
Hard Level ............................................................................................................................................... 18
Solutions ..................................................................................................................................................... 19
Easy Level ................................................................................................................................................ 19
Medium Level ......................................................................................................................................... 22
Hard Level ............................................................................................................................................... 24
Acknowledgements..................................................................................................................................... 31
Puzzles
Easy Level
1. Place all the digits from 1 to 9 in to the circles so that the sum of the numbers in each straight
line are the same.
To enter the solution, enter the numbers in the following order
2. Complete the following four 5-Letter words. The missing letters, when rearranged, spell a movie
title.
W ___ ___ Z Y
J U ___ G ___
___ L ___ Z A
___ A ___ L E
3. What are the next 5 letters in the sequence
P O I U Y ___ ___ ___ ___ ___
4. Solve this….
As oou oan oee, oy poinoer oepoacos eoero thord oetoer oito tho leoteo 'o'.
How mony oifoeront oetoero haoe boen oepoacod?
5. In each of these 5 words, can you change the underlined letter to produce 5 new
words. The new letters spell a fruit.
DATE
NUT
LIME
PEACH
PEAR
6. What is represented by this
WEEDGWEEDUWEEDAWEEDRWEEDDWEED
7. If Teresa's daughter is my daughter's mother, what am I to Teresa?
8. Alan's son Daniel, is exactly one fifth of Alan's age.
In 21 years time, Alan will be exactly twice Daniel's age.
Betty's age is exactly seven times the age of her daughter, Jessica.
In 8 years time, Betty will be three times the age of Jessica.
Determine the age for Alan, Danial, Jessica and Betty. Combine their ages, from youngest to
oldest, to create the answer to submit. For example, if the ages where 4, 5, 25 and 26, enter
452526.
9. Complete this grid with the digits 1 to 6 to make the sum correct.
Perform each mathematical operation in the order shown, from left to right, e.g. 1 +
2 x 3 is treated as (1 + 2) x 3 = 9.
Note: there is no ÷ 1, and at no point is a decimal or fraction used.
Submit the numbers, in order from left to right, with no spaces.
10. Each empty white square in the grid contains one of the numbers 1, 2, 3,…, 8. Each
of the horizontal and vertical equations must be true and each number must be used
exactly once.
Submit the numbers from Left to Right, Top to Bottom, with no spaces.
Medium Level
1. Just last week, Stacey's nieces and nephews met up to go to the cinema to see Star
Trek.
Sabrina = 1
Sally = 2
Sam = 3
Sandra = 4
Sarah = 5
Shane = 6
Sharon = 7
Simon = 8
Steve = 9
Stuart = 10
From the clues below, can you determine the order in which they stood in the ticket
queue? Create a number using the mapping above. If the list above was the correct
order then the answer to the puzzle would be 12345678910.
Sam was in front of Sarah. Stuart was behind Sandra and Sally.
Sally was in front of Sharon and Steve. Sabrina was behind
Stuart, Simon and Steve. Steve was in front of Sabrina, Simon
and Shane. Shane was behind Simon, Sharon and Sabrina. Sandra
was in front of Sarah. Simon was in front of Sam, Stuart and
Sandra. Sarah was in front of Sharon. Sabrina was in front of
Sam and Shane. Sarah was behind Sandra, Sally and Sabrina.
Stuart was in front of Sarah. Simon was behind Sally.
2. Below, 10 nine letter words have been broken into chunks of three letters. These
chunks have been mixed up, no chunk is used twice and all chunks are used.
Determine what the 10 words, and then put them in alphabetical order. The last
word alphabetically is the answer to this puzzle.
ent
cla
hai
sag
enc
sen
rbr
mar
clo
ine
oom
ise
htn
gar
col
ush
lis
age
ion
our
ile
ssr
ess
ing
erw
cro
lig
new
oth
cod
3. Place the digits 1 to 8, into the grid. The numbers you can see are the totals for the
surrounding numbers.
After solving the puzzle, enter the numbers in the order indicated by the red numbers below.
4. What is the name of the famous city?
5. The question is somewhere in the grid.
W
H
A
T
I
S
O
N
E
P
L
U
S
O
N
E
B
S
F
R
D
R
M
J
R
P
B
H
S
M
M
T
H
S
P
H
P
S
F
Z
Z
F
J
F
W
W
B
J
F
H
W
S
B
F
R
J
F
G
V
K
C
F
W
Y
S
T
P
P
D
T
L
S
Q
F
R
Y
Q
P
S
P
K
J
N
L
W
D
Z
Z
Z
W
J
F
R
R
K
F
F
P
T
M
S
B
F
N
V
Z
H
W
Q
Q
B
D
V
P
D
V
N
K
R
M
G
W
F
J
Y
J
J
L
J
N
S
R
R
K
K
B
Y
N
K
F
H
K
Y
R
P
W
W
G
T
F
Y
J
F
R
T
S
R
H
D
P
Z
L
S
B
C
B
P
Q
V
P
Z
R
S
R
Q
F
6. Below are six animals that have been split. Take a set of three letters from the left column, and a
set of three letters from the right column and merge them together again, without changing the
order of the letters in each half. Matching sets will not necessarily be on the same row.
For example WMB + OAT and OAT + WMB both equal WOMBAT as the order of the letters OAT,
and WMB remain the same.
For another example, RABBIT could become RBT + ABI.
When submitting your answer, sort the names alphabetically and enter the name of the 4th
animal.
CYO ARU
WLS DNE
EAR FEE
OKY OTE
RRT JAR
AGU BE
7. Below are 8 Academy Award winners, 4 female and 4 male. The lettters of their
names have been mixed up and put into alphabetical order. The brackets contain
the clues to their names. After decoding the names, order them alphabetically by
last name. The solution to the puzzle is the last name of the actor whose name is
last alphabetically.
For example :
ADEILNOSWW = Wade Wilson
DEEFIJOORST
EEELMPRRSTY
ABEIJLORRSTU
AABEEHHIKNNPRRTU
CEEEGGLNOOORY
ACCHIJKLNNOOS
BDEEINOORRRT
AACCEEHIILMN
8. Using these letters: AAADDEEEEKSSSS complete this square. The square reads the
same across as down.
R
*
*
*
*
*
*
*
*
*
*
*
*
*
*
K
Submit the word in the 3rd column from the left.
9. Below is a grid which should contain boy's names. The missing letters for a particular
column are listed at the top of that column. Can you 'drop' the missing letters in and
complete the grid? The highlighted letters are an actor’s name. What role is he
remembered for?
10. The map below shows the street locations of a city. Position three police officers such
that the entire length of every street can be seen by at least one officer.
When submitting, enter in the 3 letters in alphabetical order
Hard Level
1. Word games.
Take the word FALSE. Divide it between the L and the S, giving you 2 parts: FAL and SE. Use the
first part to start the word FALL, and second part is the end of the word RISE. And, of course,
"fall" and "rise" are opposites. Solve this puzzle by using the word SHALL. Divide it into two
parts, so that the first part starts one word and the second part ends another word — and those
two words are opposites. The dividing point is for you to discover. There are four different
solutions.
Each word pair will get you credit. When submitting answers, enter both words, with the first
word being the word that has the first part. For example: FALSE give you FALL and RISE, the
answer would be: FALL RISE. Do include any punctuation in your answers.
2. Not Yours
HAS
YOU
HERO
WITHIN
GALAXY
LOSS
1
WIN
1
TAKE
2
SQUARE
2
THE
2
STRAIGHT
1
SCORE
1
OF
1
WINTER
2
DRINK
2
MIX
2
FLOWER
1
BAKE
2
BEGIN
3
LETTERS
4
FROM
3
RIGHT
3
TO
2
THE
2
VOTE
3
FOUR
3
BALLOT
1
DAGGER
1
UNDER
1
DIVIDE
2
FOUR
4
ALL
4
CORNERS
2
EDGES
1
VELOCITY
1
TIME
1
2
2
1
0
0
__ __ __ __ __ __ __ __
3. A picture is worth a thousand words.
__ __ __ __
__ __ __ __ __ __ __ __ __
4. Rule
Guerr evatf sbe gur Ryira xvatf haqre gur fxl, frira sbe gur Qjnes ybeqf va gurve unyyf bs fgbar,
avar sbe gur zbegny zra qbbzrq gb qvr, bar sbe gur Qnex Ybeq ba uvf qnex guebar, va gur ynaq
bs Zbeqbe jurer gur funqbjf yvr. Bar evat gb ehyr gurz nyy, bar evat gb svaq gurz, bar evat gur
oevat gurz nyy, naq va gur qnexarff ovaq gurz. Va gur ynaq bs Zbeqbe jurer gur funqbjf yvr.
Fhozvg ynfg anzr bs gur nhgube.
__ __ __ __ __ __ __
5. Shall we play a game?
__ __ __ __ __
6. Liquid Crystal Logic
__ __ __ __
__ __ __ __ __ __ __
7. Lights out
__ __ __ __ __ __ __ __ __ __
8. Table Trouble
At a poker table, each player has some chips whose values are indicated. However, periodically,
an expert sneak thief would pass by the table and would steal a chip from each player. To
compound the shenanigans, the thief had stolen another chip from another game, but you got
the better of him and stole that chip back from him! The players’ hands are shown below, one
hand per row.
__ __ __ __ __ __ __ __
9. Quantum Leap
When Sam leap through time, he encountered many types of hazards. Can you help diagnose
Sam’s problem?
L70.4 E04.9 B35 A77.4 H02.62 A37.9 P70.3 X37.42 M20.2
Z52.6 H81.312 M41 Q21.3 M54 F18 A66.5 D73.5 E88.3
A59 B76 T75.4 F51.5 H53.53 N45.2 J47 B08.72
B42 D72.1 A07.2 O88 M72.6 M33.9 K26 V00.21 L94.4 L50.1 B58
__ __ __ __
10. The road less travelled
__ __ __ __ __
Hints
Easy Level
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
All straight lines add to 14.
The first word is WOOZY.
You would normally see these letters in the reverse order.
Why are there so many O’s.
The first word is L A T E.
Say what you see.
Who is asking the puzzle?
A little algebra might help.
The first number is 2.
The top left number is 6.
Medium Level
1.
2.
3.
4.
5.
6.
7.
Sally is first.
These are the first letters of the words: S, H, G, P, P, M, W, S, Y, O.
There is only 1 way to build 25.
Why does each column start with A and then B?
Look closely at the grid and you'll find the question. Perhaps it's written like a word search?
The first letters of the animals are B, C, D, F, J, W.
The brakets to the right of the letters give you the first letter of the first and last
name of the actor, the numbers indicate the length.
DEEFIJOORST
EEELMPRRSTY
ABEIJLORRSTU
AABEEHHIKNNPRRTU
CEEEGGLNOOORY
ACCHIJKLNNOOS
BDEEINOORRRT
AACCEEHIILMN
[J5
[M5
[J5
[K9
[G6
[J4
[R6
[M7
F6]
S6]
R7]
H7]
C7]
N9]
D2 N4]
C5]
8. One of the words begins with the letter D.
9. The on top row, the first missing name is Adam.
10. There is an officer at B.
Hard Level
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
One word uses SHALL split like SH ALL, the remainder of the answers are split like SHA LL.
Shall we play a game?
What’s common?
As a rule, men worry more about what they can't see than about what they can.
Have you see this kind of game before?
Have you ever played calculator games?
An incomplete picture.
You can’t always win at the casino, but you can win periodically.
Figuring out this puzzle might be easier than figuring out what he doctor will bill my insurance.
There is no Wi-Fi in the forest, but you’ll find a better connection.
Solutions
Easy Level
1.
The 4 words are:
W O O
J U D
P L A
L A D
Z Y
G E
Z A
L E
Letters are : O O D E P A L D, when you rearrange them, you get DEADPOOL
2. The letters are the top row of letters on the keyboard, reading from right to left.
P O I U Y T R E W Q
So the answer is TREWQ
3. If you read the text, many of the words look like real words, but the letter o is used a lot. It
turns out the message says the following, if you replace the letter “o” for the correct letter:
As you can see, my printer replaces every third letter with the letter ‘o’.
How many different letters have been replaced?
So, count the replaced letters (in red)
As you can see, my printer replaces every third letter with the letter ‘o’.
How many different letters have been replaced?
Answer: 32 (31 will also be accepted since the letter ‘o’ in How doesn’t appear to be replaced.)
4. LATE
NET
MIME
POACH
NEAR
The answer is LEMON
5. As you can see, there is a word hidden in the multiple words of WEED, GUARD. This
is a “Say What you See” puzzle. If you say what you see, you have GUARD IN
WEEDS. The answer is GARDEN WEEDS.
6. "Teresa's daughter is my daughter's mother"
my daughter's mother is actually me (i.e. the person who is asking the puzzle).
Therefore:
Teresa's daughter is me (i.e. the person who is asking the puzzle is Teresa's daughter).
Since gender is that of the reader, the following answers are accepted: SON or DAUGHTER
7. The first half of the question involves Daniel (D) and Alan (A).
Daniel is currently one fifth of Alan's age, so:
A=Dx5
(1)
In 21 years time, Alan will be twice his age, so:
A + 21 = (D + 21) x 2 (2)
Using (1) in (2) gives:
A + 21 = (D + 21) x 2
5D + 21 = (D + 21) x 2
5D + 21 = 2D + 42
3D = 21
D=7
So Daniel is 7 (and Alan is 35).
The second half of the question involves Jessica (J) and Betty (B).
Betty's is exactly seven times the age of Jessica:
B=Jx7
(3)
In 8 years time, Betty will be three times the age of Jessica, so:
B + 8 = (J + 8) x 3
(4)
Using (3) in (4) gives:
B + 8 = (J + 8) x 3
7J + 8 = (J + 8) x 3
7J + 8 = 3J + 24
4J = 16
J=4
So Jessica is 4, Daniel is 7, Betty is 28, and Alan is 35.
8.
So the answer is: 241635. Due the commutative property, the following answers are also
possible. 241536, 421635, 421536
9.
The answer is 62314578
Medium Level
1. Sally, Steve, Simon, Sandra, Stuart, Sabrina, Sam, Sarah, Sharon, Shane
So the answer is: 29841013576
2. cla + ssr + oom = classroom
clo + sen + ess = closeness
col + lis + ion = collision
cro + cod + ile = crocodile
enc + our + age = encourage
hai + rbr + ush = hairbrush
lig + htn + ing = lightning
mar + gar + ine = margarine
new + sag + ent = newsagent
oth + erw + ise = OTHERWISE
3. The solution is 16723845
4. The letters in each column are in alphabetical order. Just continue each column one more
letter, and read the word from left to right to get CHICAGO
5. Read down the first column: WHAT IS ONE PLUS ONE? The answer is 2. Two would also be
accepted.
6. EAR + BVE = BEAVER
CYO + OTE = COYOTE
OKY + DNE = DONKEY
RRT + FEE = FERRET
AGU + JAR = JAGUAR
7. DEEFIJOORST
EEELMPRRSTY
ABEIJLORRSTU
AABEEHHIKNNPRRTU
CEEEGGLNOOORY
ACCHIJKLNNOOS
BDEEINOORRRT
AACCEEHIILMN
JODIE FOSTER
MERYL STREEP
JULIA ROBERTS
KATHERINE HEPBURN
GEORGE CLOONEY
JACK NICHOLSON
ROBERT DE NIRO
MICHAEL CAINE
The solution is : STREEP
8. R E A D
EASE
ASKS
DESK
9.
The letters in the highlighted squares spell Adam West. He is know for being Batman
10. The officers are located at B, G and H. The solution is BGH
Hard Level
1. SHORT TALL
SHARP DULL
SHANT WILL (Shant has the ‘ missing in the answer)
SHAKY STILL
2. This puzzle is the game Minesweeper. Using the numbers, figure out where the mines are
located.
HAS
1
WIN
YOU
1
TAKE
HERO
WITHIN
GALAXY
LOSS
2
SQUARE
2
THE
2
STRAIGHT
1
SCORE
1
1
2
2
2
1
OF
WINTER
DRINK
MIX
FLOWER
BAKE
2
3
4
3
3
2
BEGIN
LETTERS
FROM
RIGHT
TO
THE
2
3
3
1
1
1
VOTE
FOUR
BALLOT
DAGGER
UNDER
DIVIDE
2
4
4
2
1
1
FOUR
ALL
CORNERS
EDGES
VELOCITY
TIME
1
2
2
1
0
0
The words in the box of each mine make the following sentence:
Take the straight letters from the four corners
The straight letters refers to letters that written with only straight lines. For example, X and Z
have straight lines, but S doesn’t. So we get
HAS LOSS FOUR TIME
So the answer to the puzzle is: HALFTIME
3. In this puzzle, you need to look at each row as a pair. If you sound out the word(s) for each
photo in the row, you’ll notice that the ending sound of the left photo is the beginning sound of
the right photo. If you then pronounce the common sounds, from top to bottom, you’ll get the
hint to the puzzle.
Left Photo
Shared Sound
Right Photo
Knee Cap
Cap
Captain Crunch
Rin Tin Tin
Tin
Tinsel
Black Jack
Jack
Jack Hammer
Shaq
ack
Hacker
Factor
tor
Tornado
So the sounds are: Cap-tin Jack ack-tor, and if said become “Captain Jack Actor”. The answer is
John Barrowman who played Captain Jack in Torchwood and Dr. Who.
4. This is a classic cipher puzzle. The quote is from Julius Caesar. This Caesar Cipher is a ROT13,
meaning that the plain text and cipher text is shifted left 13 characters.
abcdefghijklmnopqrstuvwxyz
Original:
Substitution: n o p q r s t u v w x y z a b c d e f g h i j k l m
So, using the above substitutions, the cipher text decodes to:
Three rings for the Elven kings under the sky, seven for the Dwarf lords in their halls of stone,
nine for the mortal men doomed to die, one for the Dark Lord on his dark throne, in the land of
Mordor where the shadows lie. One ring to rule them all, one ring to find them, one ring the
bring them all, and in the darkness bind them. In the land of Mordor where the shadows lie.
Submit last name of the author.
So the last sentence asks for the last name of the author. The quote is from Lord of the Rings
books, so the answer is Tolkien
5. This puzzle is a Nonogram (Griddler). Each cell in gray represents a group of blacked out cells, so
the 4th row has 3 numbers (1, 5, 1). That means that there are 3 groups of blacked out cells, one
for each number. The number indicates the number of consecutive cells blacked out. Between
each group is at least one white cell You can use a site such as:
http://www.griddler.co.uk/Solve.aspx. Using the above method, you get
This picture is the Question Mark block from Mario. So the answer is Mario
6. The numbers are seven-segment LCD digits. If you Exclusive OR (XOR) the LCD segments in each
string of numbers, you will get a letter for each string of numbers.
1. The string of numbers: 12791322
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
…=L
... = L
…=S
…=H
… =A
…=t
…=n
…=E
…=r
The answer is Bill Shatner
7. The different shapes stars are constellations, but with one star missing.
If you fill in the missing stars in the original picture (red stars), you’ll get the missing constellation.
The missing constellation is the answer, CASSIOPEIA
8. The words “Periodically”, “Table”, and “Compound” are small hints to the origin of the numbers.
Each chip’s number is the Atomic Number in the Periodic Table. If you place the number with
the element’s symbol, and fill in the missing element, you get the following:
P Ar I S
Ca Es Ar S Pa La Ce
P Ar I S
W Y N N
W Y N N
Co S Mo P O Li Ta n
Mg Mg Ra Nd
Ne W Fr O N Ti Er
Ca Es Ar S Pa La Ce
Mg Mg Ra Nd
These are all names of casinos. Finally you then put the missing elements (RED) in the bottom
section, and fill in the missing first element
Al I Ce I N W O N der La Nd (Alice in Wonderland)
The item you stole from the thief, Al, was the answer: Aluminum
9. If you search for the codes above, you’ll find that these are ICD 10-CM codes.
Look up the various codes. The first letter (RED) of the condition gives you the next step of the
puzzle:
INDEX WITH
LAST DIGIT
THEN DO BY
SECOND DIGIT
So using these solutions as the instructions, use the last digit of the code to index into the
description to get the second letter (in parenthesis). For example: L90.4 Infantile acne, using the
last digit “4” will index the 4th letter of “Infantile acne” = “A”. Once you have the condition
Agalactia, find the its ICD-10 code and index into it to get the letter “G” as part of the final
answer.
INDEXWITH  AGALACTIA (O92.3 -> G)
I (A) L70.4 Infantile acne
N (G) E04.9 Nontoxic goiter, unspecified
D (A) B35 Dermatophytosis
E (L) A77.4 Ehrlichiosis
X (A) H02.62 Xanthelasma of right lower eyelid
W (C) A37.9 Whooping cough, unspecified species
I (T) P70.3 Iatrogenic neonatal hypoglycemia
T (I) X37.42 Tidal wave due to storm
H (A) M20.2 Hallux rigidus
LASTDIGIT  DUSTSTORM (X37.3 -> O)
L (D) Z52.6 Liver donor
A (U) H81.312 Aural vertigo, left ear
S (S) M41 Scoliosis
T (T) Q21.3 Tetralogy of Fallot
D (S) M54 Dorsalgia
I (T) F18 Inhalant related disorders
G (O) A66.5 Gangosa
I (R) D73.5 Infarction of spleen
T (M) E88.3 Tumor lysis syndrome
THENDOBY  NOCTURIA (R35.1 -> U)
T (N) A59 Trichomoniasis
H (O) B76 Hookworm diseases
E (C) T75.4 Electrocution
N (T) F51.5 Nightmare disorder
D (U) H53.53 Deuteranomaly
O (R) N45.2 Orchitis
B (I) J47 Bronchiectasis
Y (A) B08.72 Yaba pox virus disease
SECONDDIGIT  PERITONITIS (K65 -> T)
S (P) B42 Sporotrichosis
E (E) D72.1 Eosinophilia
C (R) A07.2 Cryptosporidiosis
O (I) O88 Obstetric embolism
N (T) M72.6 Necrotizing fasciitis
D (O) M33.9 Dermatopolymyositis, unspecified with myopathy
D (N) K26 Duodenal ulcer
I (I) V00.21 Ice-skates accident
G (T) L94.4 Gottron's papules
I (I) L50.1 Idiopathic urticaria
T (S) B58 Toxoplasmosis
Using the last number to index in to the condition, you get answer: GOUT
10. As the hint suggests, the answer lies in the forest. Looking at the picture you see there are 5
tree groups, made up of short and tall trees. Each of the 5 groups represents a single letter in
the solution. The trees represent Dots and Dashes in Morse Code. The tall trees are dashes,
and the short trees are dots. So starting from the top, you get…
11.
So the answer is SPOCK
Acknowledgements
Thanks to those people who helped create and test the puzzles:
Brian Carlson (Puzzle Master)
Chris Carlson
Alicia Carlson
Melinda Carlson
Tamara Comstock
Deanna Crews
Robert Spencer