I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

What have one eye but still cannot see?

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?

Outside a tattoo artist's shop, there was a signboard which read 'I make tattoos on only them who do not tattoo themselves'.

Reading it what do you think, does the tattoo artist tattoo himself?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

Who are the happiest people in IPL match?

f you were running a race, and you passed the person in 2nd place, what place would you be in now?

Prove that the below maths equation is true.

8 + 8 = 91