Can you replace the question mark with the correct number?

If 21x = 79x, what is the value of x?

It is always ahead of me yet I can never see it. What is it?

The horse jumps over the king.
Strangely there is absolutely no scratch on him.

Can anyone explain, how is this possible?

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 breaks yet never falls, and what falls yet never breaks?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

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

Find the next number in the series.
1 10 24 43 67 ?

What goes through cities and fields, but never moves?