Find the mistake in the below maths equations

A = 2
A(A-1) = 2(A-1)
A2-A = 2A-2
A2-2A = A-2
A(A-2) = A-2
A = 1

A network of 20 x 10 squares is given to you.

Can you calculate how many unique squares and rectangles can be formed combining two or more individual squares ?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

There is something which is always coming but never arrives?

On a charity event in Russia, Murray beat Djokovic by winning six games and losing three games.
Note: There is a total of 5 service breaks(one who serve lost the game).
Who served first, Djokovic or Murray?

What is wrong in the below Picture?

There are 3 apples in the basket and you take away 2. How many apples do you have now?

Find the Next Number in the Sequence

2 9 3 1 8 4 3 6 5 7 ?

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?