**Puzzle 1: **Which number replaces the question mark?**Answer: **12

**Explanation: **The value at each corner of the diagram equals the difference between the sums of the numerical values of the letters in the boxes adjacent to the corner.

**Puzzle 2: **Which symbol replaces the question mark?**Answer: **Alarm Clock

**Explanation: **The Alarm clock = 7, the Adaptor = 5 and the Bulb = 2

**Puzzle 3: **Which grid replaces the question mark?**Answer: **E

**Explanation: **In each row, the left hand grid is symmetrical around a vertical axis, the central grid is symmetrical about a horizontal axis, and the right hand grid is symmetrical about a diagonal axis, running bottom left to top right.

**Puzzle 4: **Which grid replaces the question mark?**Answer: **3

**Explanation: **In each diagram, the numerical value of the left hand letter equals the product of the upper and lower left hand numbers, and the right hand letter equals the product of the upper and lower right hand numbers. The numerical value of the central letter equals the sum of the numerical values of the left and right hand letters.

**Puzzle 5: **Which grid replaces the question mark?**Answer: **A

**Explanation: **In each diagram, there are 2 lines of black dots, joining two sides together. The sides joined by the dots moves 1/4 turn clockwise as you move from left to right.