I have teeth but i don't bite. Who Am I ?

Find the next number in the sequence

5 12 24 36 ?

There was a greenhouse.
Inside the greenhouse, there is a white house.
Inside the white house, there is a red house.
Inside the red house, there are lots of babies.

What is It?

On a magical land of Mexico , all the animal in the land are rational.

There are 10 tigers and one goat.
Tiger can eat goat but since it's a magical land , the tiger who eats the goat , turns into goat and then can be eaten by the remaining tiger(s).

If we leave them for some time then how many goat and tiger will be there , when we come back ?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

What is next number in the pattern below:

131 517 192 123 ?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

Using Only Five 5's and any mathematical operator make sum as 37

If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

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