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

A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?

A man died and leaves Rs.10,000 in his will. There are 6 beneficiaries- his 3 sons and their wives. The 3 wives receive Rs.3960 of which Priyanka gets Rs.100 more than Tanu and Neha gets Rs.100 more than Priyanka.
Pramod gets twice as much as his wife, Tushar gets the same as his wife, and Prashant gets 50% more than his wife.

Who is married to whom?

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

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

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

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

In a mathematical quiz, you are asked the following question:

Use three 9s in a mathematical expression without dividing or multiplying to form the number one.

Can you answer the question?

Get total of 120 by using five zeros 0,0,0,0,0 and any one mathematical operator.
Do you ?

A and B have a certain number of chocolates with them. If B gives one chocolate to A, they will have an equal number of chocolates. But if A gives one chocolate to B, then A will be left with half the number of chocolates that B has.

Can you find out the number of chocolates they have right now?