You can see it everyday, But cannot touch it at will. What is it?

A boy purchased a book from a bookkeeper and gave him $100.
The cost of the book is $50 but the bookkeeper has no change, so he gets the change from the next shop and returns the boy his $50.

After some time the next shopkeeper came with the $100 note and told the bookkeeper that the note was a fraud, so he took the money back.

How much loss did the bookkeeper face?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

Can you solve this tricky maths equation problem by replacing it? mark with the correct symbol?

19834 -----: 187
15921 -----: 153
17561 -----: 139
13734 -----: ???

You need to arrange three 7 and mathematical symbols to form number 1?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

How can you take 2 from 5 and leave 4?

What does this rebus photo means?

There are two words one resembles the "state of rest" and the other is related to "writing/reading material".

Can you name these two words which also sound similar?