These brainteasers appeared in Corriere della sera after appearing in the Daily Mail.  The answers are at the end.

1.  Peter’s Headache

Peter has a terrible headache.  His doctor gave him 5 pills to relieve the pain, telling him to take one tablet every 15 minutes.  How long will it take Peter to take all the tablets?

2. Mystery Squared

How many squares are there in this drawing?

3. A Question of Age

A woman was 70 in 2000, but only 60 in 2010.  How is this possible?

4. For the Cows, a Question of Mathematics

5. How to grant Giorgio’s wishes

6.   The Inverted Triangle

7. Four Hands

8.  What is the missing number?

9.  A Puzzle

10.  The Solution?

11.  The Glasses

12.  Find the number 8

ANWERS:

1.  Peter will take all the pills in an hour (not 75 minutes as some have answered), because he will take the first immediately, that is, at the minute zero.
2. There are 40 squares.  92% of people fail this test.
3. The woman lived in 2000 BC, so in 2010 BC she was 60, and a decade later, in 2000BC, she was 70.
4. A cow = 10, a sheep = 2, and a hen = 4.  So, 1 cow + 1 hen = 14 (or 7 sheep)
5. Giorgio’s wishes:
6. Golf balls:
7. Hands: It is C.  All the others are right hands.
8. The missing number is 6.  All opposite numbers, added together, are 21.
9. The missing piece of the puzzle is C.
10. In arithmetic, algebra, Boolean logic, set theory, in programming languages, etc., the order in which the operations are performed is established by convention, which means you multiply before you add.   The solution, therefore, is 12.
11. The Glasses:
12. The number 8 is in the fifth row up from the bottom, in the second position from the right.