How many sides does a circle have?

What jumps when it walks and sits when it stands?

In the addition below, all digits have been replaced by letters. Equal letters represent equal digits and different letters represent different digits.
ABCABA
BBDCAA
ABEABB
ABDBAA
------- +
AAFGBDH
What does the complete addition look like in digits?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

A boy was locked in a room by some robbers. All that is in the room is a piano, a calendar, and a bed. The room is locked from the outside. What does he eat, drink, and how does he escape and get out?

In the Mexico City area, there are two Houses H1 and H2. Both H1 and H2 have two children each.
In House H1, The boy plays for Mexico Youth academy and the other child plays baseball.
In House H2, The boy Plays soccer for his school in Mexico and they recently have a newborn.

Can you prove that the probability of House-H1 having a girl child is more than that of House-H2?

A Child was born in Lahore, Pakistan. Still, the child is not a Pakistani citizen. why?

What can jump higher than a building?

You can hear me, but you can't touch or see me.

What am I?