Which Travels Faster? Solve below famous picture riddle:

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

How Come ??

Give it food and it will live; give it water and it will die.

What is the centre of gravity?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

There is a barrel with no lid and some wine in it. 'This barrel of wine is more than half full,' said Curly. 'No it's not,' says Mo. 'It's less than half full.' Without any measuring implements and without removing any wine from the barrel, how can they easily determine who is correct?

Today, I celebrated my 32nd birthday but I was born in 1972.
How is this possible?

What does this mean?

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Okay before we begin with the puzzle, do keep in mind that you have to answer it quickly.

You are participating in a car race. Seeking the perfect moment, you overtake the second person in the race. What positions are you in now?

A convention is held where all the big logicians are summoned. The master places a band on everyone's forehead. Now all of them can see others bands but can't see his own. Then they are told that there are different colours of bands. All the logicians sit in circle and they are further explained that a bell will ring at regular intervals. The moment when a logician knew the colour of band on his forehead, he will leave at the next bell. If anyone leaves at the wrong bell, he will be disqualified.

The master assures the logicians that the puzzle will not be impossible for anyone of them. How will the logicians manage ?