Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

Prove that twice of ten is the same as twice of eleven.

What does the below rebus riddle means?

Six glasses are in a row. The first three are filled with milk and the last three are empty. By moving only one glass, can you arrange them so that the full and the empty glasses alternate?

You have a roll of cloth 1km long. You have a machine which cuts this roll into pieces of 10-meter-long cloth.

How long would it take for the machine to cut the roll if each cut took 4 secs?

On a beautiful Sunday morning, You ordered a hot tea to your hotel room and suddenly you remember an important thing that needed to be done right now will take around 3 minutes to complete.
Like most people you like your tea to be hot while drinking so, when should you pour cream in the tea?
1. straight away
2. Just people, you drink the team
3. Its does not matter

In a football game, Christina defeated Teresa by 2 - 0 but no man from either side scored. How can this be possible?

I am not a bull but I have horns.
I am not an ass but I have a pack saddle.
Wherever I go, I leave silver behind me.

Who am I?