What do you get if you add 2 to 100 four times?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

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?

Replace the question mark with the correct number below.

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

Replace the 'X' with any mathematical symbol to make the expression equal to 111.

18 X 12 X 2 X 3 = 111

Which alphabet letter is a question?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

Can you solve the maths in the below-given picture equation?