Find the Next Number in the Sequence

2 9 3 1 8 4 3 6 5 7 ?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

A girl says this to her best friend: “I was born in 1955, and I celebrated my 17th birthday last weekend.” Her best friend thinks she’s lying, but she’s actually correct. How is that possible?

You need to move three matchsticks to form three squares. Can you do it?

How can I get the answer 24 by only using the numbers 8,8,3,3?

You can use the main signs add, subtract multiply and divide.

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

A guard is positioned at the one side of the bridge saying ‘A’. His task is to shoot all those who try to leave from ‘A’ to the other side and say ‘B’. He also need to welcome the person who comes from another side ‘B’ to his side ‘A’. The guard comes out of his post every 1 hour and looks down the bridge for any people trying to leave. You are at side ‘A’ and wish to go to another side ‘B’. you also know that it would take 1:45 hr to cross the bridge. How will you cross the bridge?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?