Follow in the footsteps of Alan Turing and Britain’s Bletchley Park codebreakers!

Find out if you have the problem-solving skills to work for the intelligence services. We’ve devilishly selected five puzzles ranging from beginner to advanced levels, with each puzzle becoming more difficult as you progress. See if you can solve these five challenges and match wits with Bletchley Park’s sharpest minds. (Puzzle answers at the bottom.)

Our puzzles are taken from SPYSCAPE’s New York City HQ collection of challenging logic and IQ puzzle books produced by the Bletchley Park Trust for SPYSCAPE.

Puzzle Question 1

What letter should replace the question mark?

Puzzle Question 2

Sarah has 24 wooden building blocks. Half of the blocks have faces measuring 12 mm square; one-third of the remainder have faces measuring 15 mm square; one-quarter of the new remainder have faces that are 18 mm square; and the rest have faces that are 21 mm square. If Sarah stacks her blocks one on top of the other to make a tower, how high would the tower be (assuming it doesn’t collapse)?

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Follow in the footsteps of Alan Turing and Britain’s Bletchley Park codebreakers!

Find out if you have the problem-solving skills to work for the intelligence services. We’ve devilishly selected five puzzles ranging from beginner to advanced levels, with each puzzle becoming more difficult as you progress. See if you can solve these five challenges and match wits with Bletchley Park’s sharpest minds. (Puzzle answers at the bottom.)

Our puzzles are taken from SPYSCAPE’s New York City HQ collection of challenging logic and IQ puzzle books produced by the Bletchley Park Trust for SPYSCAPE.

Puzzle Question 1

What letter should replace the question mark?

Puzzle Question 2

Sarah has 24 wooden building blocks. Half of the blocks have faces measuring 12 mm square; one-third of the remainder have faces measuring 15 mm square; one-quarter of the new remainder have faces that are 18 mm square; and the rest have faces that are 21 mm square. If Sarah stacks her blocks one on top of the other to make a tower, how high would the tower be (assuming it doesn’t collapse)?

Puzzle Question 3

In a game of chess, the knight can move either a square that is two squares horizontally and one square vertically or two squares vertically and one square horizontally. Therefore, the complete move looks like the letter L. By making such moves, is it possible for the knight to visit every square on the board below?

Puzzle Question 4

The owners of the five cars parked in the lot depicted below all work for the same company. Who owns each vehicle and what is his or her position in the company?

1. The person who works as a clerk is parked due north of the car owned by the receptionist.

2. Dinah’s car is parked next to (either due east or due west of) that owned by the clerk.

3. The manager’s car is directly next to and west of that belonging to the janitor, whose car is directly north of Elizabeth’s.

4. Richard’s car is further north and further west than Mike’s vehicle.

Puzzle Question 5

What numbers should replace the question marks?

ANSWERS

Puzzle Answer 1

The letter O.

In alphabetical order, the first row misses one between each letter B (C) D (E) F (G) H; the second misses two C (DE) F (GH) I (JK) L; the third misses three D (EFG) H (IJK) L (MNO) P; and the fourth misses four between each letter: E (FGHI) J (KLMN) O (PQRS) T.

Puzzle Answer 2

366mm.

The quantities are: 12 at 12 mm (144 mm); 4 at 15 mm (60 mm); 2 at 18 mm (36mm); 6 at 21 mm (126 mm); 144 + 60 + 36 + 126 = 366.

Puzzle Answer 3

Yes. Here is one possible solution:

Puzzle Answer 4

The clerk’s car is either car 2 or car 3 (clue 1), as is the janitor’s (clue 3). So car 1 is the manager’s (3), car 2 is the janitor’s and car 4 is Elizabeth’s. Thus, car 3 is the clerk’s (1) and car 5 is the receptionist’s. The accountant owns car 4. Car 2 is Dinah’s (2). Richard’s is car 1 (4) and Mike’s is car 5. Car 3 belongs to Terence.

Puzzle Answer 5

Right = 378, bottom = 132.

Following the sequence as indicated by the line, multiply the numbers in the top and bottom sectors by 3, and add 15 to the numbers in the left and right sectors, then give the circle a 90-degree turn clockwise to obtain the next in the sequence.

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