Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

There is an exact a week gap between Christmas and New Year. Hence, It is obvious that the new year that comes right after Christmas comes on the same day of the week.

A Strange thing happened in the Year 1777. Christmas occurs on Wednesday and New Year on Monday. How is that possible?

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

What is the centre of gravity?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

If "P" means "-", "Q" means "/", "R" means "+", and "S" means "*" then find the value of the following:

21 Q 7 R 9 S 10 P 13

How can you make a TV, a bed, a dog, and a car liquid?

What do you think with the below Picture ?