Can you find out which number multiplied by itself will give the output as 12345678987654321?

Spot what is wrong here in below Picture?

If,
29 - 1 = 30
9 - 1 = 10
14 - 1 = 15

Based on similar logic, Can you prove that the below algebraic equation is true?
11 - 1 = 10 ?

Your job is to measure 45 minutes if you have only two cords and matches to light the cords.

1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.

Describe your way of measuring the 45 minutes.

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

I am white when I am dirty, and black when I am clean. What am I?

There is a number which when you multiply by 3 and subtract 2 from the result, then the resulting number is the reverse of the actual number.

What is the smallest number that stands true on the statement?

There are a hundred statements.

First person says: At least one of the statements is false.

Second person says: At least two of the statements is false.

Third person says: At least three of the statements are false.

Fourth person says: At least four of the statements are false.

..

..

..

Hundredth person says: At least a hundred of the statements are false.

Analysing it, how many statements do you think are false and how many are true?