Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

Use the digits from 1 up to 9 and make 100.

Follow the rules.
=> Each digit should be used only once.
=> You can only use addition.
=> For making a number, two single digits can be combined (for example, 4 and 2 can be combined to form 42 or 24)
=> A fraction can also be made by combining the two single digits (for example, 4 and 2 can be combined to form 4/2 or 2/4)

Question: how can we do this?

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

A Shopkeeper sold a few chickens to four different customers on a particular day. It was such that each customer purchased half of the remaining chickens and half the chicken more.

Can you find out how many chicken were sold by the shopkeeper on that day if we tell you that the fourth customer bought a single chicken ?

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

What is next number in the pattern below:

131 517 192 123 ?

Can you write down eight eights so that they add up to one thousand?

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?