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

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

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

A man embarked on a questionnaire game. He kept asking the same question to whomever he found. The answer each time was different.

Can you guess what the question was?

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

What jumps when it walks and sits when it stands?

I am sure no one can have two things for dinner. what are they?

A container contains 100 eggs. They can be either fresh or rotten. What is sure is the fact that there is at least one fresh egg in that container.

If you are asked to pick two eggs randomly from the container, at least one of them will be rotten.

Can you calculate how many eggs in that container are fresh?