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

If an electric train is travelling south, then which way is the smoke going?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Create a number using only the digits 4,4,3,3,2,2,1 and 1. So i can only be eight digits. You have to make sure the ones are separated by one digit, the twos are separated by two digits the threes are separated with three digits and the fours are separated by four digits

A plane crashed between the border of Mexico and America. Where do you bury the survivors?

Can you find the dog hidden in a group of pandas?

I have Rs.50 and I spend it in the way as below.

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

I left my campsite and hiked south for 3 miles. Then I turned east and hiked for 3 miles. I then turned north and hiked for 3 miles, at which time I came upon a bear inside my tent eating my food! What colour was the bear?

What do you call a fish without an eye?