Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

What number do you get when you multiply all of the numbers on a telephone's number pad?

If 1+9+8=1, what is 2+8+9?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?

What jumps when it walks and sits when it stands?

You need to climb ten stairs. At every stair, you can either take one step up or you can jump two steps up.

In how many different ways you can climb 10 stairs?

What begins with T, ends with T, and has T in it?

The Judge knows that Alamgir was killed by his girlfriend Jasline, but the judge is unsure whether to punish her. Why?

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left hand? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be.

John was drowned by he was not wet. How?