Skip to content / Đến nội dung
ThichHocToan.com

Conditional logic and ordering · SET 1

Question 1

Switch A turns lights 1 and 2 on/off or off/on. Switch B turns lights 2 and 4 on/off or off/on. Switch C turns lights 1 and 3 on/off or off/on. Switches C, A and B are thrown in turn with the result that Figure 1 turns into Figure 2. Which switch does not work at all?

Question illustration
  1. Switch A
  2. Switch B
  3. Switch C

Question 2

To which hexagon below can a dot be added so that both dots then meet the same conditions as the two dots in the hexagon above?

Question illustration

Question illustration
  1. Figure A
  2. Figure B
  3. Figure C
  4. Figure D
  5. Figure E

Question 3

What letter is directly opposite the letter that is two letters away clockwise from the letter that is directly opposite the letter E?

Question illustration
  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H

Question 4

Switch A turns lights 1 and 2 on/off or off/on. Switch B turns lights 2 and 4 on/off or off/on. Switch C turns lights 1 and 3 on/off or off/on. Switch D turns lights 3 and 4 on/off or off/on. Switches D, C, A and B are thrown in turn, with the result that Figure 1 turns into Figure 2. Which switch does not work at all?

Question illustration
  1. Switch A
  2. Switch B
  3. Switch C
  4. Switch D

Question 5

A B C D E F G H
What letter is two letters to the left of the letter immediately to the right of the letter three letters to the right of the letter A?

Question illustration
  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H

Question 6

In the grid, which number is three places away from itself plus three, two places away from itself multiplied by two, two places away from itself less four, and two places away from itself divided by three? (Places are counted in a straight line horizontally, vertically or diagonally.)

Question illustration

Question 7

Which letter is two letters away clockwise from the letter that is directly opposite the letter three letters away anticlockwise from the letter C?

Question illustration
  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H

Question 8

Switch A turns lights 1 and 2 on/off or off/on. Switch B turns lights 2 and 4 on/off or off/on. Switch C turns lights 1 and 3 on/off or off/on. Switch D turns lights 3 and 4 on/off or off/on. Switches B, D, A and C are thrown in turn, with the result that Figure 1 turns into Figure 2. Which switch does not work at all?

Question illustration
  1. Switch A
  2. Switch B
  3. Switch C
  4. Switch D

Question 9

Each switch toggles its indicated light pair. Throw C,B,D,A to transform Figure 1 into Figure 2. Which switch is faulty?

Question illustration

Question 10

A has thought of a number between 13 and 1300, and B is trying to guess it. (1) B asks whether the number is below 500; A says "yes". (2) B asks whether it is a perfect square; A says "yes". (3) B asks whether it is a perfect cube; A says "yes". Then A says: "Only two of my answers are correct." A also says: "The number starts with 5, 7 or 9." B now knows the number. What is it?

Question illustration

Question 11

Cyril lives in a road where the houses are numbered 8 to 100. John asks "Is it greater than 50?" Cyril answers "YES". John asks "Is it a square number?" Cyril answers "YES". John asks "Is it an odd number?" Cyril answers "YES". John asks "Is the first digit an 8?" Cyril lies. What is the number of Cyril's house?

Question illustration

Question 12

Assuming four of these dates are correct, which one is wrong?

Question illustration
  1. Saturday 7 January 1764
  2. Saturday 21 January 1764
  3. Saturday 11 February 1764
  4. Saturday 11 March 1764
  5. Saturday 14 April 1764

Question 13

My friend scored a hole in one on an 18-hole course (holes 1 to 18). Five witnesses each made a statement about which hole it was: A Not an even number; B It had double digits (a two-digit number); C The number was made up of only straight lines; D Not a prime number; E Not a square number. Only one statement was true. Which hole was it?

Question illustration

Question 14

Five suspects are questioned; exactly one of them is guilty. Each makes one statement, and exactly three of the five statements are true.
Uncle Jack: Uncle Jim committed the murder.
Aunt Mary: I did not do it.
Cousin Stewart: It was not Cousin Margaret.
Uncle Jim: Uncle Jack is lying when he says I did it.
Cousin Margaret: Aunt Mary is telling the truth.
Who committed the murder?

Question illustration
  1. Uncle Jack
  2. Aunt Mary
  3. Cousin Stewart
  4. Uncle Jim
  5. Cousin Margaret

Question 15

The Pharaoh asked: “Who is the greatest of the gods?” “I am not,” said Horus. “Anubis is,” said Isis. “Isis is lying,” said Anubis. Only one god was telling the truth; the other two were lying. Who is the greatest?

Question illustration
  1. Horus
  2. Isis
  3. Anubis

Question 16

In a race of 16 horses numbered 1 to 16, I missed the finish. Six friends told me about the winner's number: A: it was even. B: it was odd. C: it was prime. D: it was a square number. E: it had 2 digits. F: it was between 6 and 12. Only four of them told the truth. Which number won?

Question illustration

Question 17

Which star is missing?

Question illustration
  1. Figure A
  2. Figure B
  3. Figure C

Question 18

SwitchA toggles lights 1,2; B toggles 2,4; C toggles 1,3; D toggles 3,4. C, A, D, B are operated in that order, changing Figure 1 into Figure 2. Which single switch fails completely?

Question illustration

Question 19

Which grid number is three places from itself−2, two places from itself/2, three places from itself−5 and three places from itself× 3?

Question illustration

Question 20

A toggles lights 1,2; B toggles 2,4; C toggles 1,3; D toggles 3,4. Operate A, C, D, B in turn. One switch fails entirely. Which switch produces the illustrated change?

Question illustration