How can you make number one disappear by adding something to it?

How can you tell a raw egg from a hard-boiled egg?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

On a bright sunny day, two fathers took their son fishing in the lake. Each man and son were able to catch one fish. When they returned to their camp, there were only three fishes in the basket. What happened?

PS: None of the fish were eaten, lost, or thrown back.

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

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

If one and a half boys, eat one and a half burgers in one and a half hours.

How many burgers can 9 boys eat in 3 hours?

If an electric train is travelling south, then which way is the smoke going?

Rahul decided to meet Simran so he boards a local train from Bombay station. Just after the station, there is a 1km long tunnel. The train starts and is now accelerating. Rahul is a claustrophobic guy, so what is the best position for him to sit?

When it is alive we sing, when it is dead we clap our hands. What is it?