Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

A woman lives in a Tall building thirty-six floors high and served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

A container contains 100 eggs. They can be either fresh or rotten. What is sure is the fact that there is at least one fresh egg in that container.

If you are asked to pick two eggs randomly from the container, at least one of them will be rotten.

Can you calculate how many eggs in that container are fresh?

There are 3 apples in the basket and you take away 2. How many apples do you have now?

If a boy blows 18 bubbles,
Then pops 6 eats 7 and then
He pops 5 and blows 1.
How many are left?

I left my campsite and hiked south for 3 miles. Then I turned east and hiked for 3 miles. I then turned north and hiked for 3 miles, at which time I came upon a bear inside my tent eating my food! What colour was the bear?

Our product and our sum always give the same answer. Who are we?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?