What is common among 11, 69, and 88?

You need to climb ten stairs. At every stair, you can either take one step up or you can jump two steps up.

In how many different ways you can climb 10 stairs?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

Move four matchsticks to the below square to form three squares?

Count the Triangle in the figure given below:

In a chess board, the queen piece can move horizontally, vertically and diagonally freely. The picture represents the same.Can you place 8 queens on the board in a manner that none of the queens can attack each other?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

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

Do you know what I am?

Replace the alphabet with the number such that the below equation holds.

HAPPY
+ DIWALI
--------------
HDLALA
--------------

In a secret society, a buried chamber can be accessed only via a secret password. The password is seven characters long and comprises of just letters and numbers.

You find a code that can help you in cracking the password. The code says "You force heaven to be empty".

Can you deduce the password from that?