Name a key which is hardest to turn.

In an Art Gallary, When the clock hit 11 am, Artist hung the painting number 30. When it struck 4 pm, he hung painting number 240 and when it struck 7:30 pm, he hung painting number 315.

Can you determine, which painting number will he hang when the time is 9:20 pm?

You stand in front of two doors. A guard stands next to each door. You know the following things: one path leads to paradise, the other leads to death. You cannot distinguish between the two doors. You also know that one of the two guards always tells the truth and the other always lies. You have permission to ask one guard one question to discover which door leads to paradise. What one question would you ask to guarantee you enter the door to paradise?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?

Ten coins have been arranged as you can see in the given picture. In this arrangement, a triangle is formed pointing upwards. You have to invert the position of the triangle and make it point downwards while changing the position of 3 coins only. Can you do it?

It is Secret Agent Bond Girl Friend's birthday but he is on a secret mission

Mr Bond has a secret device by which he can only use the below words for sending the message.

Dumbo, Nazi, Carrot, Ronda, Zambia, Racing, TinTin, Seou, Zareeba, Laltain, Saphire, Tar, Orphan, Audition, Biscotti.

Mr Bond sends the following message to her girlfriend:
Carrot Dumbo Nazi Racing Ronda Zambia TinTin Seou Laltain Zareeba Tar Biscotti Orphan Audition Snake

What does Mr. Bond's Message say?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

Why did Navjot Singh Sidhu put the new January calendar in the freezer

Can you divide the below-given shape into four equal and identical pieces?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.