Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

A girl says this to her best friend: “I was born in 1955, and I celebrated my 17th birthday last weekend.” Her best friend thinks she’s lying, but she’s actually correct. How is that possible?

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 ?

Which is heavier: a ton of bricks or a ton of feathers?

What is the largest number you can write with just 3 digits?

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

Two friends were betting. One said to the other, "The coin will be flipped twenty times and each time the coin lands on the head, I will give you $2 and each time it lands on the tale, you will give me $3." After flipping the coin twenty times not a single penny was exchanged among them.

How many times did the coin land on heads?

Identify the 10 differences between the two given pictures.

Can you fill the blank with the correct number?

6 30 870 756030 _____

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.