I throw two dice simultaneously.

What is the probability of getting a sum as 9 of the two numbers shown?

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()

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.

Solve below popular number sequence
314 159 265 358 979 323 846 ?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

How do you go from 98 to 720 using just one letter?

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

Using Only Five 5's and any mathematical operator make sum as 37

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