What has many keys but can’t open a single lock?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

Which Burger Is Different in below image?

How do you go from 98 to 720 using just one letter?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

A girl has as many brothers as sisters, but each brother has only half as many brothers as sisters. How many brothers and sisters are there in the family?

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

What jumps when it walks and sits when it stands?

What always comes into a house through the keyhole?

I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?