13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

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?

Given below is simple addition with a defined pattern pattern:
7 + 7 = 2
8 + 8 = 4
8 + 5 = 1
6 + 9 = 3
10 + 11 = 9

Can you analyze the pattern and find out the answer for:

4 + 9 = ?

Find the hidden tiger in the given optical illusion ?

If your uncle’s sister is not your aunt, what relation is she to you?

There are two words one resembles the "state of rest" and the other is related to "writing/reading material".

Can you name these two words which also sound similar?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?