MathParadise

Insert the correct mathematical signs to make the following calculations work:

7 8 20 32 = 44

9 3 42 12 = 94.5

8 2 12 9 = 57

6 7 15 13 = 44

5 32 6 20 = 18.75

If you use a certain formula on 13, you end up with 7.

Under the same formula, 2352 becomes 16, 246 becomes 14, 700 turns into 16, and 1030 becomes 14.

What would 9304 become?

Given 12 coins, one of which is false with a different weight. Determine in the minimum number of weighings which one is false and whether it’s lighter or heavier than the rest.

There are 20 people in a room. What is the probability that two of them will have the same birthday?

1) A man was to be sentenced, and the judge told him, “You may make a statement. If it is true, I’ll sentence you to four years in prison. If it is false, I’ll sentence you to six years in prison.” After the man made his statement, the judge decided to let him go free. What did the man say?

2) I can run, but never walk,
Often a murmur, never talk, I have a bed but never sleep, I have a mouth but never eat. What am I?

3)  What has three feet but cannot walk?

4)  You have a barrel of oil, and you need to measure out just one gallon. How do you do this if you only have a three-gallon container and a five-gallon container?

5)  The Pope has it but he does not use it. Your father has it but your mother uses it. Nuns do not need it. Your lady friend’s husband has it and she uses it. What is it?