Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

Your mother’s brother’s only brother-in-law is asleep on your couch. Who is asleep on your couch?

When can we add 2 to 11 and get 1 as the correct answer?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

Jessica is telling her friends this story and asks them to guess if it’s the truth or a lie: “There was a man sitting in a house at night that had no lights on at all. There was no lamp, no candle, and no other source of light. Yet, he sat in the house and read his book happily.” Her friends say she’s lying, but Jessica corrects them and says she’s telling the truth. Jessica’s story is true—but how?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

All of the flowers I have are orchids except two. All of the flowers I have are hibiscuses except two. All of the flowers I have are roses except two.

Can you tell me how many flowers I have?

French Police inspects a room where there are no windows, no doors, no tables and is almost empty expect there is just a puddle of water. They found a dead man who obviously hung herself from the ceiling, but they are not able to figure out how this had happened.

John and Jacob entered the crime scene and easily able to solve the case.

How did the man die?