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

We know that money can be names differently for the purpose it is used for. Some of the examples of money given at following places or for following activities:

In temple = Daan
In school = Fees
During marriage = Dowry
For divorce = Alimony
Paying government = Tax
In court = Fine
Employer to employee = Salary
To kidnappers = Ransom
For illegal reason = Bribe
To civil servant retirees = Pension

Do you know what do we call the money a husband gives to his wife?

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

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

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

Below toothpicks/matchsticks indicate the group of fishes moving from west to east direction. Can you make them move from east to west by just moving three toothpicks/matchsticks?

There’s a one-story house in which everything is yellow. Yellow walls, yellow doors, yellow furniture. What colour are the stairs?

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?

As shown in the image, the nine Dogs are square fenced. By constructing just two square fences can you make sure that two Dogs cannot meet each other without crossing the fence?

I have an apple tree , number of apple in this tree get doubles every week.

On 30th week , the tree gets completely filled with apples :-)



Can you tell me , on what week does my tree is half covered with apples ?