Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?

You have two rectangular wires.

Both of them have property that when you light the fire from one end , it will take 60 minutes to get completely burn.

However, they do not burn at consistent speed (i.e it might be possible 1st 20% burn in 50 minutes and 80% can burn in 10 minutes).

So how could you measure 45 minutes ?

A man lives on the fifteenth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator, or if it was raining that day, he goes back to his floor directly. Otherwise, he goes to the tenth floor and walks up five flights of stairs to his apartment. Can you explain why he does this?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

There’s a girl who has a large family. She has an equal amount of brothers and sisters, but each brother only has half as many brothers and sisters. What’s the correct amount of brothers and sisters?

What has many teeth, but cannot bite?

In a guessing game, five friends had to guess the exact numbers of apples in a covered basket.
Friends guessed 22, 24, 29, 33, and 38, but none of the guesses was correct. The guesses were off by 1, 8, 6, 3, and 8 (in random order).

Can you determine the number of apples in a basket from this information?

Jenifer is learning to drive her car. She went down a one way lane and in the wrong direction. But she do not break any law.

How come ?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?