If 1+9+8=1, what is 2+8+9?

The more of this there is, the less you see. What is it?

Why is a river so rich ?

A King wants to send the diamond ring to his girlfriend securely. He got multiple locks and their corresponding keys. His girlfriend does not have any keys to these locks and if he sends the key without a lock, the key can be copied in the way. How can King send the ring to his girlfriend securely?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

There is a box. The area of its top is 240 square units, the area of the front is 300 square units and the area of the end is 180 square units.

Can you calculate the dimensions of this box with the given data?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

Replace the question mark with the number below given a simple math problem.

I have no life, but I can die. What am I?