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

Count the number of squares in the picture below.

What is black when you buy it, red when you use it, and gray when you throw it away?

The more it dries, the wetter it becomes. Can you tell what it is?

Using the clues below, what four numbers am I thinking of?

The sum of all the numbers is 31.
One number is odd.
The highest number minus the lowest number is 7.
If you subtract the middle two numbers, it equals two.
There are no duplicate numbers.

Teacher ask the student

'Why are you standing on that chair in music class ?'.

what did student replied ?

You have 10 balls with you. A friend of yours out of nowhere asks you to place those ten balls in five lines such that each of the lines has exactly 4 balls on them. He needs to check your intelligence. Prove him by doing the task.

Replace the 'X' with any mathematical symbol to make the expression equal to 111.

18 X 12 X 2 X 3 = 111

1 rabbit saw 9 elephants while going to the river. Every elephant saw 3 monkeys going toward the river. Each monkey had 1 parrot in each hand. How many animals are going towards the river?

Replace all '*' with digits 1, 2, 3, 4, 5 and 6 to make below statement true.

* *
x *
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* * *