There was a man he lives in a hotel each morning he presses the first floor button each evening if there is a person in the elevator he asks him to press the 10 floor button if there is no one in the elevator he takes the stairs why.

There is a jar in which there are two types of candies.
20 blueberries and 16 strawberries. You perform the following steps:
1) You take out two candies.
2) If the two candies are of the same flavour, you add a blueberry one otherwise, you add the strawberry one.

You repeat these two steps till there is just one candy remaining in the jar. Which flavoured candy will be left?

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

What can you hold in your right hand, but never in your left hand?

What four weights can be used to balance from 1 to 30 pounds?

what does the below rebus mean?

Can you make the below equation true by using any three numbers from "1, 3, 5, 7, 9, 11, 13 and 15"?

( ) + ( ) + ( ) = 30

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

Find the next number in the series.
1 10 24 43 67 ?