Can you find out which number multiplied by itself will give the output as 12345678987654321?

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?

Find out the missing number in the picture attached:

Find the number of squares in the below-given picture.

On one occasion, A Boy collects 71 rupees in form of 20 paise and 25 paise. He collects a total of 324 coins.

Can you tell me how many 20-paisa and 25-paisa he got?

Can you find the largest Three-digit number whose sum is 14 and whose square is less than 5,00,000?

What is next number in the pattern below:

131 517 192 123 ?

0 0 0 = 6
1 1 1 = 6
2 2 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

You can use any mathematical symbols in the space provided to make all above algebraic expressions true.

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?