Move four matchsticks to the below square to form three squares?

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

John was writing his first book. After saving the document, he locked his laptop with a password and mentioned some phrases for the hint box.

A friend of his tried opening his laptop but found out that it was password protected. Following is the hint that appeared.
1 mobile 3 books 2 roars 1 night 4 balls 2 lighters 1 ghost 1 hat 3 watches.

Can you help him in cracking the password?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

Find out the missing number in the picture attached:

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

Count the number of triangles in the picture below:

What Adam and Eve do not have but the rest of the people have?