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

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

Can you find a number that lies one third of the distance between 1/3 and 2/3?

Find the next number in the sequence

5 12 24 36 ?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

Things are just as they seem, right? Well, check again.
Can you count the number of tigers in this picture ?

Who has married many women but was never married?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

There is so small cabin inside a deep forest.
All the forest burned out to worst possible but the inside of the cabin is still the same.
However all the person inside the cabin die.

How come ?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?