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

Why is a river so rich ?

In which direction should the missing arrow point?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

Can you spot the man between the coffee bean in the picture below ?

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

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You can see three almost identical images below. Can you spot the odd one out from them?

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Green Balls costing $6
Yellow Balls costing $3
Black Balls costing $0.10

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