If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

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

You walk into an old horror house. It has no power or plumbing. Once inside, you see three doors. Each door has a number on it. Behind each door is a way for you to die. Behind door number one, you die by getting eaten by a lion. Behind door number two, you die by getting murdered. Behind door number three, you die by an electric chair. You can’t turn back, so you have to go through a door. Which door do you go through?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

John and his wife were living in a rural place. On a particular day, John's wife fell ill and he called the local doctor. When the doctor picked up, he said, "Doctor, my wife is ill. She might have appendicitis."

"This can't be possible! I took out her appendix two years ago myself," the doctor explained.

When diagnosed, John's wife was found to have appendicitis. How can this be possible?

It's pretty hard to give up.
If you remove a part of it, you will be left with a bit.
Even if you remove another part, the bit still remains.
Remove one more and it still remains.

What is it?

Why do people go to bed?

I have branches, but no fruit, trunk or leaves. What am I?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?