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

There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

Take away the whole and some still remain. What is it?

A man was driving a black truck. His lights were not on. The moon was not out. A lady was crossing the street. How did the man see her?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

Whats the next number in the below number sequence pattern.

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Can you move 2 matchsticks to form four equal sized squares.

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Can you calculate how many answers given by you were wrong?

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How do you measure 45 minutes?