Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?

In a classic wine shop, the list of three most popular wines are:
- The cost of 1 French wine bottle: 500$
- The cost of 1 German wine bottle: 100$
- The cost of 20 Dutch wine bottles: 100$

John entered the wine shop and he needs to buy
- All three types of wine bottles.
- Needs to buy Dutch wine bottles in multiples of 20.
- Need to buy 100 wine bottles in total.

John has only 10000$. How many wine bottles of each type, John must buy?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

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

What does this simple rebus mean?

As we know that white starts the game of chess. Can you find the scenario shown in the picture below is possible when all the white pieces are at the original place while the black pawn is not as in the below picture?

What happened when the wheel was invented?

You have a 12 liters jug full of water. You have two empty 8 liters and 5 liters jug. How can you divide the water into two equal parts using these jugs?

If 2 workers can complete painting 2 walls in exactly 2 hours.

How many workers would be needed to paint 18 walls in 6 hours?