Hard Riddles

Hard riddles with answers are a true test of your brain power, reasoning and comprehension. You are sure to find these tough difficult riddles both challenging and puzzling. While these hard riddles and answers may drive you a little crazy sometimes, they may surprise you in the way they force you think out of the box.

10 Bottles 100 Pills

There are 10 identical bottles of identical pills. Each bottle contains 100 pills. Out of 10 bottles 9 have 1 gram of pills but 1 bottle has pills of 1.1 gram in weight. Given a measurement scale, how would you find the heavy bottle? You can use the scale only once.

Riddle Answer

Treasure Lock Key

In a cave there is a treasure within a big metal box with a lock on it. There is also a monster in the cave that has two keys with him; one gold and the other silver. The monster will give you only one chance to open the lock using one of the keys. If the box doesn’t open, the monster will kill you. Since the monster is a bit helpful it would give you a clue in finding out the correct key. Can you choose the correct key by deciphering the below clue?

A GKOY OEPD LYEO DCNO EAAR NNN

Riddle Answer

100 Prisoners and a Light Bulb

There is a prison with 100 prisoners, each in separate cells with no form of contact. There is an area in the prison with a single light bulb in it. Each day, the warden picks one of the prisoners at random, even if they have been picked before, and takes them out to the lobby. The prisoner will have the choice to flip the switch if they want. The light bulb starts off.

When a prisoner is taken into the area with the light bulb, he can also say “Every prisoner has been brought to the light bulb.” If this is true all prisoners will go free. However, if a prisoner chooses to say this and it’s wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.

Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.

What strategy could they use to ensure they will go free?

Riddle Answer