A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

John has played 50 ODI's and his average is 50. How many runs should he score in his 51st ODI, so that his average score jumps to 51?

I am a three digit number.
My tens digit is five more than my ones digit.
My hundreds digit is eight less than my tens digit.
What number am I?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

Which of the below owl is odd one out?

I have an eye but still cannot see.

Who am I?

Your mother’s brother’s only brother-in-law is asleep on your couch. Who is asleep on your couch?

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?