81 x 9 = 801. What must you do to make the this equation true?

It has five wheels, though often think four, You cannot use it without that one more, You can put things in it, you can strap things on top, You can't find it in the market, but you can still go shop. What is it?

We know that money can be names differently for the purpose it is used for. Some of the examples of money given at following places or for following activities:

In temple = Daan
In school = Fees
During marriage = Dowry
For divorce = Alimony
Paying government = Tax
In court = Fine
Employer to employee = Salary
To kidnappers = Ransom
For illegal reason = Bribe
To civil servant retirees = Pension

Do you know what do we call the money a husband gives to his wife?

I can be cracked, made, told, and played. What am I?

Do You See It?

What do you see in the given picture?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?

A doctor and a boy were fishing. The boy was the doctor’s son, but the doctor was not the boy’s father. Who was the doctor?

'S' refers to the number of seconds in a day and 'H' refers to the number of hours in ten years. Which quantity out of these two is greater?