You are on a Boat in the mid of a river. You have two cigarettes with you. One of these two you have to light, how will you light the cigarette?

A lion and its tamer are standing inside a cage that measures 1 unit in radius. Both of them can effortlessly run at the speed of 1 unit maximum.

1) Suppose the lion is hungry, will he be able to eat up the tamer?
2) If yes, how long can the tamer survive?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

Replace the question mark with the correct number in the below-given picture?

If eleven plus two equals one, what does nine plus five equal?

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

I am thinking of a five-digit number such that:
The first and last digits are the same, their submission is an even number and multiplication is an odd number and is equal to the fourth number. Subtract five from it and we obtain the second number. Then divide into exact halves and we get the 3rd number.

What number I am thinking of?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

If a shopkeeper can only place the weights on one side of the common balance. For example, if he has weights 1 and 3 then he can measure 1, 3 and 4 only. Now the question is how many minimum weights and names of the weights you will need to measure all weights from 1 to 1000? This is a fairly simple problem and very easy to prove also.