What has lots of eyes, but can’t see?

How many times can you subtract the number two from the number fifty?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

Complete the following series. It.s very logical:

1, 4, 5, 6, 7, 9, 11, __?

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

I’m orange, I wear a green hat and I sound like a parrot. What am I?

Find the next number in the following series:
6, 14, 26, 98, __?

How many times can you subtract the number 5 from 25?

13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?